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Olli Aumala
NETWORKING FOR MEASUREMENT EDUCATION
IMEKO TC1 has started a series of On Line (virtual) Workshops and a Portal for joint use of educational material. The aim of this activity is to help educators in organizing good co-operation and getting benefit of synergy in their work. The educators’ work includes classroom teaching and supervising of students, but also developing and collecting educational material, and preparing textbooks, lecture notes, exercise collections, demonstrations, etc. for educational use. Transferring new scientific results into a new form suitable for education is not a minor duty. The paper presents experience from the first Workshop and discusses needs, difficulties and methods in development of networking.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Dariusz Buchczik, Witold Ilewicz
TEACHING OF MEASUREMENT PROCEDURES FOR SPECIALITY OF MEASUREMENT SYSTEMS IN THE INSTITUTE OF AUTOMATIC CONTROL
Ability to prepare, perform and process data obtained during an experiment is essential skill for engineers. At Measurement System Group at the Silesian University of Technology run the speciality Measurement Systems. At this speciality there is a course on Measurement Procedures. The course is performed for students of the 8th semester. The half-year lecture course is supported by classes and laboratory classes at the same semester. The lecture shows the procedures and fields of their applications. It is intended to show variety of procedures and complexity of process of choosing a proper method to the task. The aim of classes is to illustrate the lecture. There are solved hypothetical problems that refer to selected sections of the lecture. The laboratory classes are intended to develop self-reliant proficiency in using procedures on real and simulated data. Students solve problems, perform computations, comment and interpret results.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Krzysztof Chrzanowski
SOFTWARE FOR EVALUATION OF UNCERTAINTY IN MEASUREMENTS
Software ASSISTANT enabling calculation of uncertainty of measurements is presented in this paper. Mathematical algorithm used by Assistant was developed according to recommendations of European Co-operation for Accreditation. Assistant is equipped with a user friendly interface and offers its users a series of examples of uncertainty calculations. Reports generated by Assistant can be saved, printed or exported to popular formats: Microsoft Word, Microsoft Excell or RTF. All these features make Assistant a useful tool in centres that implemented quality systems, in scientific laboratories or in teaching metrology.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Stanislaw Dlugosz
MODELLING OF TECHNICAL OPERATION IN RELATION TO MEASURING MEANS
One can notice a great need of improvement in designing quality. This problem concerns also a specific branch of factories that produce electronic measuring instruments. We are using new generation electronic circuit, for example: the microprocessor system. They are further called "functors". Their application to get unified functional scheme of measuring instruments. Their use simplifies assembling. A short term "measuring means" is proposed in order to search uniformity of terminology. It describes technical means for measurement purposes. The MM's is created as a result of realisation of multistage process of technical operations. The process can be divided into to parts. The first one contains "creations" and another contains "products". The model presented can be useful for training future engineers with respect to creation and understanding the creation process.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Ewa Dziuban
HUMAN BODY TEMPERATURE MEASUREMENT-CLASS PROGRAM
Training class concerning "Human body temperature measurement" supports adequate part of lectures on Medical Measurements led by author on IX semester of speciality Metrology and Measurement Systems, faculty of Electrotechnics and Computer Science at Technical University of Rzeszow.
Author established the program of class with the aim of familiarising students with IR radiation thermometers (pyrometers): their basic principles (infrared theory), construction and basic metrological problems (spectral range, field of view, resolution, accuracy and errors). Recently the infra-red ( IR) radiation thermometers for medical application are intensively advanced and wildly distributed.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Christian Eugene
WHAT AND HOW TO TEACH AT THE UNIVERSITY LEVEL IN A BASIC ELECTRICAL MEASUREMENTS COURSE THROUGH A PROBLEM-BASED LEARNING APPROACH?
A completely new engineering curriculum has been introduced in 2000-2001 at our University with a modern pedagogical approach, the keywords of which are problem-based learning, project-based learning, active learning. The lecture will, as an introductory part, present the why’s, what’s and how’s of this revolution.
This new context of teaching, which privileges the knowledge acquisition through practice better than theory, certainly favours creativity and especially motivation. But consequently, the place for formal, traditional courses is reduced to a small portion of the curriculum.
It is in particular the case for the courses in electrical measurements and instrumentation, of concern in this lecture, in the new curriculum of students in electrical engineering. Furthermore, the necessary rigour inherent to any training programme in this discipline becomes difficult to achieve in a pedagogical method enhancing the selftraining.
It is in this context of limited time budget that a recentering is needed on what is essential to keep in a basic training in electrical measurements and instrumentation for every student in electrical engineering. A rapprochement with the course of electrical circuits is also a new accent to be emphasised.
The lecture will draw up a list of uncircumventing topics which will be commented often through very simple examples. Only low frequency measurements (below 1 MHz) are here considered.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Takanori Yamazaki, Yoshiharu Sakurai, Hideo Ohnishi, Masaaki Kobayashi, Shigeru Kurosu
CONTINUOUS MASS MEASUREMENT IN CHECKWEIGHERS AND CONVEYOR BELT SCALES
This work is concerned with the development of a signal processing algorithm for checkweighers to realize much higher speed of operation and highly accurate measurement of mass of object during crossing a conveyor belt. Continuous measurement means that masses of discrete objects on a conveyor belt are determined in sequence. Checkweighers usually have maximum capacities of less than 75 kg and achieve measuring rates of 150 packages per minute and more. The output signals from the checkweighers are always contaminated with noises due to vibrations of the conveyor belt and the object in motion. In this paper an employed digital filter is of Finite-duration Impulse Response (FIR) type that can be designed under the consideration on the dynamics of checkweighers. The experimental results on checkweighers suggest that the filtering algorithm proposed in this paper is effective enough to practical applications.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Kazuhiro Kodama, Tomohide Kesamaru, Motoyuki Adachi, Kazuyuki Kamimura, Shigeru Kurosu
FORCE-MEASUREMENT USING GYROSCOPIC FORCE MEASURING SYSTEM
This paper concerns the development of an entirely new force sensor called Gyroscopic Force Measuring System (simply called GFMS) for measuring a force vectorially. In a previous paper, the dynamical characteristics and the error analysis of the GFMS for measuring a force vector in 3-dimensional space were examined using numerical simulations. The results of this work are directly applicable to design and construction of the GFMS. In this paper, the GFMS is constructed by a gyro-rotor used a miniature rate-gyro for aircraft instrument and mechanical parts together. In order to verify the principle of the GFMS, our prototype GFMS made on first trial is able to measure the only one component of a force vector, excluding servomechanisms to estimate angles of incidence. The feedback gains are selected somewhat arbitrarily, but the fundamental experiments show that the force less than 0.3 N can be measured by the GFMS. This suggests the possibility to measure a small force range useful for air-flow distribution in an air-conditioned room as an example of expected applications. No doubt the experimental results are to be released in a future publications.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
L. Doering, J. Frühauf, U. Brand
MICRO FORCE TRANSFER STANDARDS
The measurement of material properties and dimensional metrology are often carried out by mechanical probing using small spherical probing balls. Well-known instruments, such as microhardness measuring instruments, atomic force microscopes, stylus instruments and coordinate measuring machines operate in this way. With increasing miniaturisation and high precision requirements for measurement, these probing systems become ever finer, i.e. the radius of the probing spheres used becomes ever smaller. It therefore is necessary to increase the resolution and accuracy of the measurement. This reduction of the probing sphere diameter leads to the reduction of the probing forces required in order not to destroy the surface of the workpiece to be measured. Small probing forces are needed in particular, when soft materials are measured, i.e., in the ideal case, the probing force should be zero. In reality a force is, however, necessary to deflect the stylus tip and to ensure permanent contact between the stylus tip and object measured. These small probing forces below a few mN therefore have to be measured very exactly. For these purposes, different kinds of silicon bending beams or cantilevers, respectively, have been examined. Two types of micro force sensors were investigated: active and passive sensors. Passive sensors, which consist of calibrated bending beams can be used as micro force calibration standards. Active sensors also consist of Si bending beams but with integrated piezoresistive strain gauges for measuring the beam deflections during probing. Commercially available cantilevers, which were originally produced for application in atomic force microscopes and cantilevers manufactured by the Faculty of Electrical Engineering and Information Technology of the Chemnitz University of Technology were investigated as micro force transfer standards and sensors.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Kazunaga Ueda, Toshiyuki Hayashi, Koji Ohgushi, Hiroshi Maejima, Yukio Yamaguchi
A PROPOSAL OF AN EVALUATION METHOD OF UNCERTAINTY IN THE TRACEABILITY SYSTEM OF FORCE
This paper proposes a new approach for evaluating the uncertainty in the traceability system of force with the following features. a) Repeatability/reproducibility is evaluated by the Type A evaluation. b) Data taken in each orientation is treated with equality. c) Deviations from reference values and from the interpolation equation are considered to be equal to the standard deviation 1s of a normal distribution. d) Difference of the values in increasing load and in decreasing load are considered as a half-width of the possible distribution of values to be measured. The same is the case of difference of the zero points in a loading cycle.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Andrei Marinescu, Gheorghe Opran, Dorin Popa, Amritlal Sawla, Günther Haucke
STABILITY OF THE 32 MN FORCE CALIBRATION MACHINE AND INDUSTRIAL APPLICATIONS
In 1997 the High Force Calibration Laboratory from ICMET Craiova was accredited by DKD. The laboratory has a metrological test and calibration machine for the range 0.5 MN to 32 MN and the traceability to the German standard is ensured by means of periodic checks with 2 MN, 5 MN and 16 MN transfer standards of PTB and 2 MN and 10 MN transfer standards of ICMET. The paper contains a short presentation of the 32 MN machine, the results of its periodical checks performed within 1995-2002. A special attention is paid to the tests performed in 2001 with 2 MN and 16 MN PTB transfer standards according to EN 10000/3-94 and DKD procedure, as well as the tests of measuring equipment used in industrial applications. The aim of these tests was to check the long-term stability of the metrological performances of the machine reference measuring system.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
F. Tegtmeier, M. Peters
MULTICOMPONENT SENSOR FOR STRESS ANALYSIS IN BUILDINGS
An important element in the supervision of buildings is the necessary precise and continuous measurement of stress conditions. For this purpose, an encapsulated measuring sensor as developed which protects the sensitive strain-gauge technology within it and which can be easily inserted into measurement boreholes. The mechanical adaptation is effected by optimising a process of deformation of two conical bodies such that the envisaged measuring range covers the range of elastic deformation of construction steels. Suitable calibration procedures as well as measurement methods for the early detection of structural damage in buildings were developed for this adaptation model. A strain-gauge layout was devised for the sensor that is adapted to the specific local conditions, and the strain gauge is protected by a plastic seal. In order to be able to assess the lifetime of the sealing materials, which in part were being employed for the first time, the chemical/climatic building environment was simulated under forced conditions in the laboratory.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Claudia Santo, José Fuentes, Juan M. Curbelo
ESTIMATION OF UNCERTAINTY IN ANALYTICAL BALANCES - COMPARISON OF MASS MEASUREMENTS PERFORMED IN ANALYTICAL BALANCES (LATU-1999)
The current paper provides the details of the main sources of uncertainty that occur when conventional mass determinations are performed in analytical balances. The data presented correspond to the calibration of 18 analytical balances that belong to LATU, together with the detailed quantification of each of the sources of uncertainty. The results of a comparison of conventional mass measurement performed in those balances with a Teflon sample are assessed, considering their uncertainty values. Conclusions are subsequently drawn on conventional mass measurement's reproducibility in analytical balances in LATU.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
A. A. El-Sayed, H. M. El-Hakeem, B. Gloeckner, T. Allgeier
PERFORMANCE EVALUATION AND METROLOGICAL CHARACTERISTICS OF A DEADWEIGHT FORCE STANDARD MACHINE WITH SUBSTITUTE LOAD CONTROL SYSTEM
A new dead weight force standard machine covering the range from 5 kN to 500 kN direct weights has been designed and constructed at the National Institute for Standards (NIS)- Egypt, by Gassmann Theiss Messtechnik GmbH (GTM). The machine capacity can be duplicated to 1000 kN by means of a substitute force generator. The machine has been verified through a comprehensive Inter-laboratory Comparison Programme run over a period of two years at the Physikalisch-Technische Bundesanstalt (PTB) of Germany and NIS of Egypt. A well-selected set of high precision force transfer standards was used in the comparison calibration protocol. Rounds of measurements were carried out on deadweight machines at both the PTB and NIS. This paper presents the protocol followed to evaluate the metrological characteristics of the new machine as well as the Inter-laboratory Comparison scheme used in the verification process. The results prove that the machine achieve an uncertainty better than 2·10-5 for calibration of force transducer by pure deadweights. Using the substitute force generator mechanism to double the machine capacity resulted in an uncertainty figure better than 1·10-4.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Koji Ohgushi, Takashi Ota, Kazunaga Ueda, Eiji Furuta
DESIGN AND DEVELOPMENT OF 20 kN·m DEADWEIGHT TORQUE STANDARD MACHINE
A deadweight torque standard machine of rated capacity 20 kN·m (20 kN·m-DWTSM) was designed and developed, following the development of a 1 kN·m torque standard machine (1 kN·m-DWTSM) at NMIJ/AIST. This machine has a variety of features enabling it to perform precise measurements of torque, including double aerostatic bearings used in the form of a fulcrum. This paper outlines the torque standard machine.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Cezary Kaczmarek, Zdzislaw Kaczmarek
SENSORS OF IMPULSIVE FORCE AND PRESSURE WITH ONE POINT AND TWO POINT STRAIN MEASUREMENT APPLIED IN TASKS OF RECONSTRUCTION
In the paper the structure and the operating principle of impulsive force and pressure sensors applied in tasks of reconstruction is presented, which feature one point and two point measurement of the strain inside a Hopkinson bar type mechanical transducer. A comparison between the two versions of the sensor was carried out, taking into consideration the processing accuracy, the complexity of the conditioning circuit and the input signal processing circuit. The preferred application range is given for each version of the sensor.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
K. Baethke, M. Faulstich, G. Haucke, A. Dájer Espeleta
INVESTIGATION OF A NEW 1 MN FORCE CALIBRATION MACHINE OF TWIN CYLINDER DESIGN
Three new force calibration machines covering the range from 1 kN to 1 MN has been designed and constructed at DM-SIC in Bogotá, Columbia. The 1 MN force calibration machine (fcm) is a reference force calibration machine of new design. A special flexible sealed twin piston cylinder system with rotating cylinders has been used for the generation of hydraulic forces to reduce the friction, oil losses and pressure drops in the hydraulic system. Time optimization and a high accuracy of force control could be achieved by a three-step combination of rapid preliminary positioning, a PI controller algorithm and, finally, a changeover to PID controller characteristics. The relative deviations between the measurements carried out at PTB and the final measurements performed in the 1 MN reference force calibration machine show that the fcm fulfils the predetermined overall specifications limits of relative uncertainty < 2·10-4 in the whole working range from 40 kN to 1 MN.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Boris Katz
A NEW WAY TO MINIMIZE UNCERTAINTY IN CALIBRATION PROCESS OF FORCE TESTING MACHINES
The results of the calibration of load cells (force transducers) according to ISO 376-1999 are described in table of values where force F (kN) is a function of electric signal R (mV/V) and by analytical approximation of the calibration curve. The analytical approximation is usually expressed by polynom of 2nd or 3rd degree. The measurement of force in the calibration of testing machines by means of digital unit device DMP-40 (HBM) suppose application of linear interpolation between two adjacent values of signal R. By means of mathematical calculations it is theoretically proven in which cases the linear interpolation is undesirable and leads to additional interpolation error, and increasing of the value of uncertainty measurement in accordance. A few studies and experiments of the issue confirm the theoretical conclusions: in some cases minimizing interpolation error and uncertainty measurement in measuring force F as a function of reading the signal R, can be achieved by approximation polynom instead of linear interpolation between two adjacent values. For this purpose QCC Hazorea has developed program called “MABA-2000,” which can solve this problem.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Andreas Subaric-Leitis, Christian Wöhry, Bernhard Seiffert, Christian Ullner
CHARACTERIZATION OF THE DYNAMIC BEHAVIOUR OF MATERIAL TESTING MACHINES
Material test results may depend strongly on the dynamic properties of the used testing machines. Unique methods and parameters for characterisation and validation of force or displacement controlled testing machines are still missing. In the presented paper a study of the control behaviour of a spindle driven uniaxial machine is carried out using a piezoelectric translator for generating the disturbance variable. The typical responses of the systematically optimized machine are compared to simulations of simplified controller systems. Some parameters concerning the time behaviour are discussed in terms of a systematic characterisation of the machine's dynamic properties and the experimental set up used.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Roman Schwartz, Andreas Lindau
THE NEW GRAVITY ZONE CONCEPT IN EUROPE FOR WEIGHING INSTRUMENTS UNDER LEGAL CONTROL
A new European gravity zone concept has been developed by WELMEC, the European Cooperation in Legal Metrology. This concept is independent of political or administrative borders and is accepted by all WELMEC member states regardless of existing national regulations concerning gravity zones. The new concept is based on gravity zones defined in terms of the geographical latitude φ and the height above sea level h, on a standardised gravity formula used for the adjustment of a weighing instrument to a reference gravity value, and on a uniform criterion for calculating the maximum permissible variation Δg/g within an individual gravity zone. The concept is of advantage especially for weighing instruments of class III. It offers an option that can, but must not be chosen by a manufacturer.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
L. Stenner, J. Andrae, R. Kumme, J. Mack
EXPERIENCE WITH A NEW CLASS OF FORCE TRANSFER STANDARDS
International force standard machines provide ever increasing accuracy. As a result the requirements for the force transducers used for international comparison measurements are also rising. The development of new force transducers shows that it is possible to reduce their measurement uncertainties. This paper describes the measuring bodies of these force transducers and the necessary selection method. The results of measurements obtained in force calibration machines and in force standard machines are presented.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Andreas Brüge
FAST TORQUE CALIBRATIONS USING CONTINUOUS PROCEDURES
Unlike step procedures, continuous procedures permit calibrations to be carried out within a very short time. In continuous calibrations the fast change in torque and thus also in the signals give rise to specific problems. This paper gives advice on how to limit the influence of the most important effects on the measurement uncertainty. A simulation method is introduced, which allows the contribution of the reference creep to the measurement uncertainty to be calculated.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Andre Zander, Rolf Kumme
ANALYSIS OF THE DYNAMIC TRANSMISSION BEHAVIOUR OF PIEZOELECTRIC FILM SENSORS
The goal of this analysis was to obtain knowledge about the dynamic transmission behaviour of piezoelectric film sensors based on Polyvinylidenefluoride (PVDF). Therefore a crossvalidation to the well-known behaviour of strain gauges based on constantan foils was conducted. The test equipment was composed of a shaker and a test piece with affixed sensors. The test piece was stressed through the connection to a load mass. The film sensors based on PVDF were mounted to the test piece in such a way that the load direction was parallel to the longitudinal axis of the PVDF-material. In this way it was guaranteed that the highest piezo strain constant d31 was mainly used. The output signals of the sensors were measured and the frequency response of the piezo film sensors in relation to the strain gauges were calculated. The results indicated that for frequencies above approx. 250 Hz the piezo film sensor frequency response modulus was a constant value with respect to the strain gauges and that for this frequency range there is the possibility to determine a specific transmission value of the used piezo film sensors similar to the “k-factor” of strain gauges. Furthermore, the high pass filter characteristic of the chosen charge amplifier could be identified.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Dieter Kenzler, Jörg Oblasser, Andreas Subaric-Leitis, Christian Ullner
UNCERTAINTY IN TORQUE CALIBRATION USING VERTICAL TORQUE AXIS ARRANGEMENT AND SYMMETRICAL TWO FORCE MEASUREMENT
Calibration machines up to a torque range of 20 kN·m need extensive design if the force is performed by dead weights. A machine based on two force reference standards and a vertical torque axis may serve to avoid these specific problems. The precision force transducers work at a lever arm of precision length. The test piece is mounted in vertical arrangement between a hydraulically operating rotary-actuator and the torque measuring system. Such a calibration machine allows additionally performing easily continuous calibration. Regarding an overall relative uncertainty not greater than 2·10-4 there are some significant problems. The estimation of the uncertainty has been proved by comparative tests with the national torque standard by the PTB according to the guidelines EA-10/14 and EA-2/03.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Hans W. Werner, Emil Harreus
FORCE TRACEABILITY MEASUREMENTS TO ACHIEVE 0.005 % BEST MEASUREMENT CAPABILITY
The increasing accuracy of force transducers and their calibration had two major effects: the chance to better extract the capability of a reference standard machine (compared to a formerly mixed evaluation of machine plus transducer) and on the other hand the need to build up reference standard machines capable to calibrate those high precision transducers. Using the experience of designing force transducers, of constructing calibration machines and of calibrating force within the German Calibration Service (DKD) since 1977 HBM decided to take the challenge. Two new dead-weight force reference standard machines of 2.5 kN and 25 kN have been built up and their best measurement capability of significantly better than 0.01 % has been verified by transfer transducers from HBM´s product range.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
R. Kumme, O. Mack, B. Bill, Ch. Gossweiler, H. R. Haab
DYNAMIC PROPERTIES AND INVESTIGATIONS OF PIEZOELECTRIC FORCE MEASURING DEVICES
Piezoelectric measurement chains are widely used in many applications of dynamic force measurements, since these sensors offer a wide useable frequency range due to their high stiffness. Typical applications of piezoelectric force sensors are described in this paper. In general, the transducers are calibrated by quasistatic or continuous calibration methods. This contribution describes the dynamic properties of piezoelectric force measuring devices and methods to determine the dynamic response of the piezoelectric force measuring chain.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
D. Ratschko, C. Schlegel, F. Scholz, M. Gläser
MASS SPECTROSCOPY OF A MIXED XENON-GOLD ION BEAM
An analysis of an ion beam produced through sputtering of gold by means of Xenon ions in a CHORDIS ion source was performed. The composition of the extracted ion beam was investigated via mass spectroscopy using a double focussing dipole magnet. From the high resolution mass spectrum the abundance pattern of stable Xe isotopes was varified and the amount of charge transitions from 2+ → 1+ could be estimated. A maximum gold current of 0,8 mA directly behind the ion source was measured.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Oliver Mack
INVESTIGATION OF THE INFLUENCE OF DISTURBING COMPONENTS ON A PIEZOELECTRIC FORCE TRANSDUCER
For the measurement of the physical quantity force with conventional transducers it is assumed that the preferred direction of the force transducer is the same as that of the vector of the force. In practice this case is rarely being observed. Due to insufficient alignment of the transducer or of the measurement facility mechanically disturbing components such as bending moments, shear forces or additional axial forces occur which may influence the measurement result significantly. This paper deals with the investigation of the influence of static mechanical disturbing components on a piezoelectric force transducer. To determine a disturbing sensitivity of a piezoelectric force transducer different kinds of experimental setups are discussed. The measurement results show a characteristic direction depending disturbing sensitivity of piezoelectric force transducers, which is well known of piezoelectric accelerometers. The investigations point out that the influence of mechanical disturbing components on piezoelectric force transducers cannot be neglected for precision measurements.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Reinhold Vollmert, Günther Ramm
REALIZATION, MAINTENANCE AND DISSEMINATION OF THE MEASURAND "AC VOLTAGE RATIO IN MV/V" FOR STRAIN GAUGE MEASUREMENTS
Strain gauges allow the measurands force, pressure, torque or strain to be converted into voltage ratios and to be indicated by measuring amplifiers. Precision measurements are preferably carried out at 225 Hz and at voltage ratios of up to 2 mV/V. Bridge standards, which have to be traced back to national standards, are used for the electrical calibration of these measuring amplifiers. More than 15 years ago, in PTB the first measuring arrangement for this purpose has been developed and installed. The present contribution explains the traceability principle of bridge standards, shows the long-term stability of selected bridge standards on the basis of measurement results and brings first investigations into the interchangeability of measuring amplifiers up for discussion.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Udo Milz
DYNAMIC WEIGHING AND DOSING WITH FAST INTELLIGENT TRANSDUCERS FIT
We present new, weighing sensors with integrated electronics, specially optimized for dynamic weighing and dosing. There is already extensive signal processing in the transducer, with all the necessary functions for fast weight value acquisition and for full, local dosing control.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Thomas Allgeier, Ulrich Kolwinski, Daniel Schwind
JOCKEY-WEIGHT LEVER MACHINES FOR FORCE AND TORQUE
This paper describes a new type of standard machine, based on a travelling (jockey) weight moving along a lever which is supported on strain-controlled elastic hinges. It is equally applicable to the quantities force and torque. In addition to step-by step loading, the machine can perform continuous calibrations without having to rely on a reference transducer. Furthermore, testing through the zero load condition is possible with suitable mounting components. In the case of force machines, the jockey-weight design allows to tare the weight of all load introduction components, so that loads as low as 0.05 N can be applied without a reduction of accuracy. Design and operating principles of the standard machines are described, with particular emphasis on their application to modern calibration practices such as continuous calibration, together with some typical test results obtained so far.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Thomas Allgeier, Helmut Gassmann, Ulrich Kolwinski, Peter Giesecke
MULTI-COMPONENT MEASUREMENT TECHNOLOGY FOR FORCES AND MOMENTS
This paper introduces the requirements and possibilities of simultaneous force and moment measurements in industrial testing. Apart from describing the principal mechanics of force and moment vectors, important implications of ignoring disturbing components are mentioned. This is followed by an overview of practical applications of multicomponent measurements. The main part of the paper describes a new measurement tool for the data acquisition, evaluation and vector analysis. This comprises issues of transducer selection and applicability, details of the electronics used and also addresses the software design. Examples of typical applications of the entire system are given with an emphasis on outlining the mode of operation and ease of adaptation to new problems. Finally, the principles of system calibrations are described.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Günter Doemens, Dieter Spriegel, Hans Wünsche
MICROSYSTEM FOR CAPACITIVE FORCE AND TORQUE MEASUREMENT
In the fields of automation, drives and production engineering the measurement of force and torque is of particular importance for the monitoring and control of industrial processes. Today’s sensors applied for this purpose are mostly based on strain gauges with a limited range of applications. Reasons therefore are rooted in the short duty cycle, the poor overload safety and the complex mounting. In order to avoid the disadvantages mentioned an innovative micro-system based capacitive force and torque sensor has been developed. By attachment at two distinguished points the sensor is mountable in an easy and robust manner on static and rotating parts.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Douglas T. Smith, Shane Woody, Jon R. Pratt
COMPACT FORCE SENSORS FOR LOW-FORCE MECHANICAL PROBE CALIBRATION
The loading mechanisms of instrumented indentation machines are often calibrated using deadweights. In many cases, due to the geometry of the loading frame, the applied deadweight is tensile, while the indentation loads to be measured are compressive. In this paper, we report preliminary efforts to develop a compressive load cell for use on a typical instrumented indentation machine. Two devices were evaluated, one a compact capacitance-based device (fabricated at the National Institute of Standards and Technology), the other a piezoresistive force sensor. We will describe the calibration sensitivity, stability and drift of each, and discuss the potential use of each as a force transfer artifact for the calibration of instrumented indenters.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
John A. Kramar, David B. Newell, Jon R. Pratt
NIST ELECTROSTATIC FORCE BALANCE EXPERIMENT
We have designed and built a prototype electrostatic force balance for realizing forces in the micronewton range. The active electrodes are concentric cylinders, the outer serving as the reference and the inner suspended and guided by a rectilinear flexure mechanism. The geometry has been designed such that a near-linear capacitance gradient of 1 pF/mm is achieved at a working overlap of 5 mm. We have used this balance in a null-displacement mode to compare an electric realization of force with the force generated by calibrated deadweights of nominal mass 1 mg, 10 mg, and 20 mg. The preliminary measurements reported here agree to within a few parts in 104 after including all known correction factors.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Jon R. Pratt, David B. Newell, John A. Kramar
A FLEXURE BALANCE WITH ADJUSTABLE RESTORING TORQUE FOR NANONEWTON FORCE MEASUREMENT
The NIST electrostatic force balance compares mechanical probe forces to an SI realization of force derived from measurements of the capacitance gradient and voltage in an electronic null balance. As we approach the nanonewton regime, the finite stiffness of the guiding flexure in the balance becomes a limiting factor. Here, we consider an equal arm balance mechanism constructed using flexure pivots as an alternative to the compound rectilinear spring of the present design. We review how the sensitivity of such mechanisms can be adjusted either by manipulating the center of gravity, or by applying a negative restoring torque using a spring. We examine tradeoffs associated with tuning the stiffness of these mechanisms with regards to tilt sensitivity and various nonideal flexure behaviors. Results obtained with a prototype mechanism are presented.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Weilu Shang, Yan Wang, Tao Li, Zhaojun Qian, Dongsheng Zhang, Mingbang Lin
ELIMINATING THE ADDITIONAL INERTIA IN MEASURING THE NATURAL FREQUENCY OF A TORQUE SENSOR
In measuring the natural frequency of a torque sensor, one must apply excitation through some mechanism which produces additional inertia coupling to sensor that the original or instinct data can not be gotten. A method was developed which can eliminate these inertia by testing and calculating. The principle, experimental method, instrumentation and results were described in detail in this paper.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Dan Mihai Stefanescu, Tiberiu Manescu
MULTI-COMPONENT FORCE AND TORQUE BALANCES FOR WIND TUNNELS
Starting from the German experience in the field of electrical measurement of mechanical quantities, one of the top application is the six-component measuring of the aerodynamic load torsor. For these complicated mechatronic devices, which have to measure six widely different components with the same relative accuracy, a complex mechanical and electrical analysis has been performed concerning the optimum positioning and connecting of the strain gauges, in order to increase the sensitivity and to compensate the disturbing influences. Four original strain gauged multicomponent balances for scale model testing were designed and manufactured having in view the improvement of the road vehicle and aircraft performances. Concrete data are shown in the four figures and tabularly summarized.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Andreas Lindau, Rolf Kumme, Andrea Heiker
INVESTIGATION IN THE LOCAL GRAVITY FIELD OF A FORCE LABORATORY OF PTB
It belongs to the functions of the National Institutes of Metrology to realise a force scale of highest accuracy. The uncertainty of the resulting force basically depends on the precise knowledge of local gravity acceleration. This paper describes the spatial determination of the local gravity field in the force laboratory of the PTB on the basis of a new highly precise gravity network. A special emphasis is placed on the influence due to gravity of the surrounding masses placed in the laboratory on the single gravity value. It can be shown that the installation of the new 2 MN deadweight force standard machine has led to a significant change in the local gravity field. Temporal variations caused by earth tides are proved by long-term registrations and are considered in a correction term for the gravity value. The periodical change of gravity reaches a level of 10-7 g in the equator region and at present does not affect the uncertainty budget of the force measurement.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Leonardo D’Acquisto, Roberto Montanini
DESIGN AND SET-UP OF A BI-PENDULUM IMPACT TESTING MACHINE
In this work the design and set-up of a bi-pendulum testing rig able to perform low-velocity impact measurements on small and medium-size components is reported. Experimental tests were conducted both to check the theoretically calculated value of the equivalent impacting mass and to quantify the overall energy losses during the idle movement of the mass. In order to provide useful information on the material behaviour during a crash test, the impact testing machine has been instrumented with different sensors: a piezoelectric accelerometer placed on the impact mass to measure the horizontal acceleration, an optical sensor to measure the initial impact velocity, a piezo film load cell, developed by the Authors, placed on the sample holder block, to measure the impact force directly on the specimen.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Jongho Kim, Yonkyu Park, Daeim Kang
DESIGN AND FABRICATION OF A THREE-COMPONENT FORCE SENSOR USING MICROMACHINING TECHNOLOGY
This paper describes a design methodology of a tri-axial silicon-based force sensor with square membrane by using micromachining technology (MEMS). The sensor has a maximum force range of 5 N and a minimum force range of 0.1 N in the three-axis directions. A simple beam theory was adopted to design the shape of the micro-force sensor. Also the optimal positions of piezoresistors were determined by the strain distribution obtained from the commercial finite element analysis program, ANSYS. The Wheatstone bridge circuits were designed to consider the sensitivity of the force sensor and its temperature compensation. Finally the process for microfabrication was designed using micromachining technology.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Miroslav Kopecky, Ivan Letko, Vladimir Cuth, Jan Vavro
TESTING EQUIPMENT FOR FATIGUE TESTS OF STEEL CORDS
The contents of the paper point out the necessity of combining the theoretical and experimental approaches in the investigation of tyre load in vehicles. The models are planar and they model the cross-section of the tyre enabling the consideration of the bottom load and the internal pressure in the tyre, as well as the influence of the lateral force. The paper presents the findings, the formulations necessary for solving the task obtained in the experimental model tests and serving as a basis for comparison with the results obtained from purely theoretical approaches, e.g. by the method of finite elements, with identical load conditions.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Jin-Wan Chung, Kyung-Ho Chang, Woo-Gab Lee, Kwang-Pyo Kim
AIR DENSITY DETERMINATION USING 1 KG BUOYANCY MASS COMPARISON(III)
In calibration of secondary 1 kg stainless steel mass standard from a platinum-iridium kilogram prototype, a major uncertainty arises from the measurement of air density for the buoyancy correction. This paper is continued to the reference. An experimental determination of air density using buoyancy pairs and a vacuum balance has been carried out and its results were compared with those of the CIPM formula 81/91. The environmental measurement instruments used for this experiment are different from those previously used. Also the true mass difference between buoyancy pairs in vacuum was measured at mass laboratory of NMIJ in Japan and compared with the KRISS result. The disagreement between air density measurements by the 1 kg BA-pair and those by CIPM formula is 5.1 x 10-4 kg/m³, but the standard deviation of the difference between both methods has been improved, to 5.3 x 10-5 kg/m³ compared to 1.5 x 10-4 kg/m³ by the previous experiment.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Kamlesh K. Jain, S.K. Jain
BEST MEASUREMENT CAPABILITY OF THE NEWLY DEVELOPED 5 kN DEAD WEIGHT FORCE MACHINE
This paper describes the salient features and the results of metrological performance of the newly developed 5 kN dead weight force calibration machine. Two well characterized strain gauge force transfer standards of 2 and 5 kN full capacity having repeatability better than 0.002% in compression mode were used to derive the best measurement capability of ± 50 ppm (k = 2) of the machine.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Carlo Ferrero, Carlo Marinari
THE DISSEMINATION OF THE FORCE UNIT IN ITALY: CALIBRATION OF MATERIAL TESTING MACHINE INTERCOMPARISON
One of the most important activities at European (EA) and National level of the National Accreditation Body (NAB) is the organisation of a series of interlaboratory comparisons (ILC), to verify the measurements capability of the calibration laboratories. In 2001 one ILC, for the calibration of uniaxial testing machines, was organised in Italy by SITIMGC with the IMGC-CNR as reference laboratory. In the present paper the main results obtained during the ILC are discussed, in particular a regression analysis was applied to evaluate the differences on the repeatability and accuracy given by the different laboratories.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
C. Ferrero, C. Marinari
CHARACTERISATION OF REFERENCE TORQUE WRENCHES BY THE IMGC SIX-COMPONENT CALIBRATION SYSTEM
This paper describes the metrological characterisation of two Reference Torque Wrenches (RTW) of 100Nm and 500Nm capacity. The characteristics of the torque sensors were evaluated by using the IMGC-CNR sixcomponent calibration system (EUROMET agree facility, project 113). The repeatability of the absolute variation of the output signal of the two TTS under the application of the different spurious components, referred to the R.O., is in general of the order of 5·10–5. The sensitivity to spurious components are normally better than 2·10–3 of the nominal torque.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Željko Alar, Mladen Franz
TRACEABILITY IN FORCE MEASUREMENT IN REPUBLIC OF CROATIA
In this study, based on results of the previously performed calibrations and factory specifications, an analysis of force measurement equipment in Republic of Croatia has been done. Transfer force standards of the Laboratory for Testing Mechanical Properties ( LIMS) have been calibrated in HBM, Germany. Calibration curves for specific transfer standards were obtained, to be used for estimation of standard uncertainties. Also, expanded measurement uncertainty was calculated at each measuring point, according to the document EA-4/15. This was used for determining the best measuring capability of the Laboratory, as well as for developing of the equipment calibration scheme for force measurement in Croatia. The previous and last calibration results for the same transfer standards were compared and, further to it, certain conclusions were made on how characteristics of the standards are influenced by use during certain period of time.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Heikki Kajastie, Jorma Manninen, Kari Riski
DENSITY CALIBRATIONS AT MIKES
The density measurement instruments at MIKES will be described. Also a construction of a instrument for weights 1 g – 200 g will be presented. The main test results will be given.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Jorge C. Torres-Guzmán, Amritlal Sawla, Daniel Ramírez-Ahedo
FORCE STANDARDS COMPARISON BETWEEN PTB (GERMANY) AND CENAM (MEXICO)
A force comparison was carried out between the Centro Nacional de Metrología, CENAM (in Mexico) and the Physikalisch-Technische Bundesanstalt, PTB (in Germany), in order to estimate the level of agreement for the realization of the quantity and the uncertainty associated to its measurement. The comparison was carried out in a range starting at 2 kN and up to 150 kN. In order to achieve best accuracy of the force transducers used was made of 5 sub ranges (5 kN, 20 kN, 50 kN, 100 kN and 150 kN). The results obtained, the deviations graphs that include the uncertainty for each laboratory are presented in this document.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Yon-Kyu Park, Rolf Kumme, Dae-Im Kang
DYNAMIC INVESTIGATION OF MULTI-COMPONENT FORCE SENSORS USING HARMONIC EXCITATION
This paper describes the dynamic investigation of a 3-component and a 6-component forcemoment sensors using the facilities in the PTB (Physikalisch-Technische Bundesanstalt) in Germany. The 3-component sensor has the transverse forces Fx and Fy of each having 200 N capacity and a twisting moment Mz of 10 N·m capacity and the 6-component sensor has force components Fx, Fy and Fz each having 200 N capacity and moment components Mx, My and Mz each having 20 Nm capacity. The sensitivity of the sensors decreases as the frequency increases and the sensors show almost 90o symmetry due to their geometry.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Jong-Ryeol Noh, Jae-Young Jeon
DEVELOPMENT AND EVALUATION OF 6-COMPONENT LOAD CELL FOR LAND-BASED TEST OF HELICOPTER ROTOR DYNAMICS
A 6-component force transducer was developed and evaluated for small-scale model test of helicopter rotor dynamics. The evaluation of the transducer was done mainly through interference check using multi-component calibration procedures. In this paper, the design and analysis process and the related results are verified through calibration results. The force transducer was designed to fix to rotating hub, and dominant force component was lifting force with maximum 1000 lb. From rotating characteristics, fail-safe structure was required to prevent the rotor from bursting out in case of rotor failure. The sensing element was designed with structural symmetry for selfcompensation by full bridge circuit and the expected deformation was analyzed by using finite element method.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
C. Dogan, O. Akkoyunlu, C. Kuzu
DEVELOPMENT OF THE 1 kN·m STATIC TORQUE STANDARD MACHINE AT UME
In the last decade, the increase in the need for the accuracy of the torque metrology created an obligation to produce a new torque standard machine for precise measurement of torque. This paper summarizes the torque standard machine designed and manufactured at UME with the range from 2 N·m up to 1 kN·m. In this machine torque is realized by a lever-mass system. Nominal force arm length of the lever is 0.5 m and constant. In each side of the lever, there are 6 different weight sets; and each set is containing 13 individual mass-stacks. For minimizing the torque loss at fulcrum an aerostatic bearing is used, and the change in the lever position due to the dead weights loading is corrected.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Aimo Pusa
TRACEABILITY OF THE CALIBRATION OF TEST CAR FOR ROLL BRAKE TESTER
The calibration of the roll brake tester for trucks has been made general by direct loading of the force transducer. That means to ignore the complete force transmission to rollers, which are in contact to trucks wheel. To be able calibrate exactly the braking force the Finnish institute YTOL has developed a test car to measure direct this braking force. The car has an extra axle with free rotating wheels and braking equipments as well the torque measuring devices. The axle can be moved in vertical position to have the weight maximum 4000 kg on the axle. Raute-MIKES had the task to realise the calibration of this measurement device. The calibration has been made with a 20 kN·m reference torque transducer, which is calibrated static by PTB. The calibration of the brake measurement system has been made as dynamic with the speed of braking as static.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Paul Hohmann
CONCEPT OF A TORQUE CALIBRATION UNIT FOR LOW RANGES BASED ON AIR BEARING COMBINATION
The need to calibrate torque in low ranges is given in case of dentist tools, viscometry or friction measurement in ball bearings. Ranges starting about 0,005 N·m as an example, is the target of the following description. A theoretic possibility is shown how to handle all disturbing influences in using mass beam systems as a basic quantity.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Biserka Mladinic, Tijana Parlic-Risovic
ADDITIONAL CONTROL OF AMBIENT CONDITIONS IN MASS METROLOGY AND ITS INFLUENCE ON MEASUREMENT QUALITY
Mass determination by use of mass comparators is influenced by different parameters including the conditions of ambient air. Having a look at the temperature of weights and the gravitational field gradients, the relatively small impact of these parameters on mass determination can be easily determined on the base of reproducible measurement results. Of metrological interest is the air density determination and control during a measurement series that could be used to improve the quality of measurement. The influence of temperature change as a function of time and its control simultaneously during the weighting process is discussed. The implementation and use of small climate chambers around the mass comparators to smooth out the temperature and relative moisture variations is described and discussed.
18th Conference on Force, Mass and Torque, Celle, Germany, 2002
Franco Maloberti
HIGH-SPEED HIGH-RESOLUTION DATA CONVERTERS FOR BASE STATIONS: TECHNOLOGIES, ARCHITECTURES AND CIRCUIT DESIGN
This paper presents a possible evolution of base station architectures in the frame of the future global communication scenario. Moving from such a view the paper considers the technology trend and its influence on highspeed data converter design. Then, architectures of highspeed, high-resolution converters are resumed. Finally, design techniques and strategies for achieving the requirements of base-station systems are discussed.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
António Cruz Serra
NEW TRENDS IN ANALOG TO DIGITAL CONVERTERS TESTING
In this paper, new state of the art analog-to-digital converters (ADCs) testing techniques both static and dynamic are revised and discussed.
Regarding the static test it is shown that a new technique based on the use of small triangular waves superimposed with a variable offset value as input signal, reduces dramatically the test duration. This histogram based technique can be implemented by using low cost generators even for high resolution ADC testing.
In relation to the dynamic test, a variant of the traditional histogram test using Gaussian noise as stimulus signal is discussed. It allows the test of high frequency, or high resolution ADCs in those cases where the traditional sinusoidal stimuli are not available with the required spectral purity. New techniques to grant convergence of the traditional four-parameter sine fitting algorithms traditionally used in time domain tests are also revised.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
R A Belcher, C Asteriou, C J Bury, A Edwards, R Hall, G Lancelin, M Penny
A DSP BASED TEST SYSTEM FOR 'NOISE-SEPARATION' MEASUREMENTS ON ADC AND DAC SYSTEMS
This paper describes the design and application of a 'noise-separation' test system that uses in-system programmable logic devices and a digital signal processor. This offers a low cost approach to multi-tone testing of the wide-bandwidth linearity of both ADC and DAC systems. As the test signal bandwidth is software configurable and uses 1 bit D-A converters it can be applied to a much wider range of applications than more conventional multi-tone test methods. Time-domain processing is expected to provide meaningful results for routine tests in a much shorter time than with FFT analysis.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Y. C. Jenq, Qiong Li
DIFFERENTIAL NON-LINEARITY, INTEGRAL NON-LINEARITY, AND SIGNAL TO NOISE RATIO OF AN ANALOG TO DIGITAL CONVERTER
The Analog to digital converter (ADC) has been widely used in all kinds of modern electronic instruments, so it is desirable to find out the relationship between various errors and the performance of ADC and improve the performance with a low cost operation. This paper studies and tries to quantify the relationship between the differential non-linearity (DNL) error, the integral non-linearity (INL) error and the signal to noise ratio (SNR) performance of an ADC, and investigates various methods to reduce the effect of these errors to increase the SNR. Major results are obtained by computer simulation, while a simple analytic model is also investigated. It is found that the loss of SNR due to DNL roughly follows the “6 dB per LSB” rule, and the major cause of the significant SNR loss is primarily due to harmonic distortion introduced by the INL. The investigation of the analytic model of the INL shows that it can predict the SNR loss very similar to the result obtained by computer simulation. We also study various methods to improve the SNR performance of the ADC. It is found that the Midpoint method, although simple, can almost completely eliminate the effect of the INL. It is also shown that if the ratio of the sampling frequency to the input signal frequency is large, the DNL can be further reduced to improve the SNR by Grouping and Sorting method.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
M. Fonseca da Silva, A. Cruz Serra
A NEW ROBUST FOUR PARAMETER SINE FITTING PROCEDURE
In this paper a new procedure to perform four parameters sine fitting is presented in a closed form, ready for standardization. This new procedure grants convergence of the algorithm, even in those cases where the traditional techniques tend to converge to local minimums of the error function.
This new procedure can also be used to compute the initial values for the traditional four parameters sine fitting algorithm if very high accuracy is required. In such case convergence of the traditional algorithm is also assured.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Jan Holub, Josef Vedral, Miroslav Kubín
IMPROVEMENT OF STEP-GAUSS ADC STOCHASTIC TEST METHOD
Improvement of Analog-to-Digital Converters testing method that is suitable for testing of high-resolution AD converters (e.g. Σ-Δ or dither-based) or on the contrary ultra high-speed AD converters is presented. The method is based on the histogram test driven by stochastic signal with defined probability density function. By repeating of the test for different settings of band-pass filter that is inserted to the input testing signal path it is possible to obtain an estimation of frequency dependency of effective number of bits. The results have to be recalculated to equivalent band-pass filtering. Practical demonstration confirmed wider applicability than for direct band-pass filter application.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
E. Nunzi, P. Carbone, D. Petri
ESTIMATION OF DELTA–SIGMA CONVERTER SPECTRUM
Effects of the windowing process, widely investigated by the scientific literature for narrow–band components embedded in white noise, is not sufficiently detailed when signals are corrupted by colored noise. Such a phenomenon can heavily affect the spectral parameters estimation of the noisy signal. In this paper effects of the windowing on the output of analog–to–digital converters with ΔΣ topology, which present a spectrally shaped quantization noise, is analyzed. In particular, the spectral leakage of both narrow– and wide– band components is investigated and a criterion for choosing the most appropriate window for any given modulator resolution is given. The proposed analysis validates the use of the Hanning sequence as the optimum two term cosine window to be employed for characterizing low order ΔΣ modulators.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Vladimir Haasz, Jaroslav Roztocil , Dominique Dallet, David Slepicka
COMPARISON OF PARAMETERS OF SYSTEMS USED FOR AD CONVERTERS AND MODULES TESTING
The paper presents results of ADC testing systems comparison between Laboratoire de microélectronique IXL, University Bordeaux and ADCM&T Laboratory, Dept. of Measurement of FEE CTU, Prague. The comparison was performed using transportable reference AD device designed and developed in FEE CTU.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Jan Holub, Olli Aumala
DATA PROCESSING AND DITHER ENHANCEMENT OF ADC PARAMETERS – TRENDS, APPLICATIONS, LIMITS
There is no noise-free place on Earth. Most of noisy effects are undesirable and unwelcome, especially in measuring technology. However, there are some measuring methods and algorithms using noise for quality enhancement. These processes are usually called dithering. Basic ideas of these methods were partially assumed from audio and video signal processing many years ago. The field of dithering technologies in measurement became large in recent years.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Henrik Lundin, Mikael Skoglund, Peter Händel
A FRAMEWORK FOR EXTERNAL DYNAMIC COMPENSATION OF AD CONVERTERS
External correction of analog-to-digital converters is considered. First, a dynamic correction scheme is proposed to comprise bit-masking. Next, a framework for analyzing the effects of bit-reduced table indexing is derived. This framework is finally applied in an optimization problem for bit allocation in the bit mask of the introduced correction scheme.
Both the dynamic correction method and the optimization problem are exemplified with experimental AD data. The results indicate that the considered correction scheme is superior to static schemes, and that the choice of bit mask is crucial, motivating the analysis framework.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Anna Domańska
THE EQUALITY OF QUANTIZATION WITH DITHER SIGNAL AND OVERSAMPLING FROM THE POINT OF VIEW OF THE CRITERION OF SNR
SNR is a characteristic of analog-to-digital (A/D) conversion. One of its applications is the valuation of the “effect” of the change of the resolution of A/D conversion. SNR may be improved by modifying the process of discretization in terms of time (sampling) and value (quantization).
The present article discusses the equality of these two types of modification from the point of view of the criterion of SNR.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Voicu Groza, Boris Dzerdz
FPGA BASED IMPLEMENTATION OF A PREDICTIVE FLOATING-POINT ANALOG-TO-DIGITAL CONVERTER
Floating Point Analog-to-Digital Converters (FP-ADC’s) were developed and used to quantize large dynamic range signals in applications where large signals need not be encoded with a precision greater than that required for small signals. Comparing floating-point with uniform quantization, it was shown that FP-ADC requires much smaller silicon area for the same dynamic range, but at the cost of doubling the conversion time.
To improve the resolution and speed of conversion of such an FP-ADC, a higher precision predictive floatingpoint architecture was conceived (PFP-ADC). The PFPADC consists of two parallel uniform A/D converters, a D/A converter, a fixed-gain amplifier and a subtraction circuit. The current subtrahend of the subtraction circuit is based on the previous sample acquisition, while the current minuend is the measured signal itself. Determination of mantissa and exponent occurs in parallel.
This paper presents the principle used to improve the resolution of FP-ADC quantized signals, and its proofof- concept FPGA based implementation. The resulting improved SNR that was achieved by using the proposed FP-ADC is better than that of other FP-ADCs, while the conversion time is shorter due to the use of prediction techniques and statistical characteristics of the measured signals.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
P. Daponte, R. Holcer, L. Horniak, L. Michaeli, S. Rapuano
USING AN INTERPOLATION METHOD FOR NOISE SHAPING IN A/D CONVERTERS
Digital post processing of output data is often used to enhance the ADC Effective Number Of Bits (ENOB). In particular, it can be used to partially recover ENOB restrictions caused by nonlinearities. The paper deals with advantages and disadvantages coming from the application of a proposed nonlinearity correction method based on the Bayes theorem. It allows the reduction of large scale errors in output signal by means of the use of dithering with low peakpeak voltage instead of a high amplitude one. The paper gives a brief description of the method. Then, the results of an experimental investigation carried out on actual ADC output data are presented and discussed.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
P. Arpaia, P. Daponte, S. Rapuano
A STATE OF THE ART ON ADC MODELING
The state of the art of the research on modelling of analog-to-digital converter-based measuring devices is surveyed. Main topics of modelling are reviewed according to the fields of prevailing scientific interest in metrological research such as quantization models, error models, and correction-aimed models. In these fields, recent developments are analysed with the aim of focusing both the contemporary situation and the imminent trends.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
G. Pasini, P. A. Traverso, D. Mirri, F. Filicori
TIME-DOMAIN EXPERIMENTAL CHARACTERIZATION OF NONLINEAR DYNAMIC EFFECTS IN S/H-ADC DEVICES
The input/output relationship of a Sample/Hold and Analogue-to-Digital Conversion device (S/H-ADC) can be described as the response of a non-linear system with memory. A general-purpose “black-box” behavioural approach, based on a modified Volterra representation, has been proposed by authors for the modelling of a wide class of non-linear dynamic systems and specifically applied to the characterization of S/H-ADCs. In this paper, the instrumentation set-up and the experimental procedure for the extraction of S/H-ADC model parameters are presented and a novel standard for the characterization of non-linear dynamic effects in this family of measurement systems is proposed.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
G. Bernardinis, A. Centuori, U. Gatti, P. Malcovati, F. Maloberti
BAND-PASS SIGMA-DELTA MODULATOR WITH 5 MHZ BANDWIDTH AND 80 MHz IF
In this paper we present a sigma-delta modulator for wide-band base transceiver station receivers. The modulator, based on a four-path architecture, achieves an equivalent sampling frequency of 320 MHz, although the building blocks operate at only 80 MHz. The circuit in simulation achieves 94 dB signal-to-noise ratio with a signal bandwidth of 5 MHz centered around an intermediate frequency of 80 MHz. Behavioral simulations of the complete sigma-delta modulator, including the most important non-idealities, as well as transistor-level simulations of the most critical building blocks are reported.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
F. Attivissimo, N. Giaquinto, M. Savino
CHEBYSHEV POLYNOMIALS AND DITHER TECHNIQUES FOR STATIC CHARACTERISTIC LINEARIZATION IN A/D CONVERTERS
The paper illustrates a new procedure, simple and very fast, to measure and correct the linearity error in A/D converters. The method is based on the Chebyshev polynomial synthesis of the static characteristic via frequency-domain analysis, and is especially effective for dithered converters.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Y. C. Jenq
FOURIER SPECTRUM OF D/A OUTPUTS WITH NON-UNIFORMLY SAMPLED DATA AND TIME-VARYING CLOCKS
In this paper, we investigate problems of D/A converters with non-uniformly sampled input data, and/or time-varying clock sources. The input digital data (which are stored in the memory to be read out and sent to a D/A converter) were obtained by sampling an analog waveform at non-uniform sampling intervals. (Quantization of data can also be considered as a form of non-uniform sampling.) Recently, there is available a new clocking system with a very fine time resolution and is capable of adjusting the clock period in a sample-to-sample basis. It is, therefore, interesting to consider the following question. "Given that the timing offset of each data sample is known, would it be beneficial to use this offset to adjust the read-out timing of the D/A converter?" To answer this question, we consider the following five different models: f1(t) = Σn x(n T) g(t - n T), f2(t) = Σn x(tn) g(t - n T), f3(t) = Σn x(n T) g(t - tn), f4(t) = Σn x(tn) g(t - tn), and f5(t) = Σn x(tn) gn(t - tn) where x(.) is the input analog signal, g(.) is the basic output pulse waveform of the D/A converter, T is the nominal sampling period and tn is the n-th sampling time instance (for uniform sampling tn = n T). Closed form expressions for the Fourier transform of the output signals for each model are derived. We also discuss some potential practical applications.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Salvatore Nuccio, Ciro Spataro
A SOTWARE TOOL TO ESTIMATE THE MEASUREMENT UNCERTAINTIES IN THE A/D CONVERSION BASED INSTRUMENTS
In the paper we present a numerical method, which permits to evaluate the measurement uncertainties of the A/D conversion based instruments overcoming the possible inapplicability of the pure theoretical approach prescribed in the ISO – "Guide to the Expression of Uncertainty in Measurement".
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Jerome J. Blair
CORRECTED RMS ERROR AND EFFECTIVE NUMBER OF BITS FOR SINEWAVE ADC TESTS
A new definition is proposed for the effective number of bits of an ADC. This definition removes the variation in the calculated effective bits when the amplitude and offset of the sinewave test signal is slightly varied. This variation is most pronounced when test signals with amplitudes of a small number of code bin widths are applied to very low noise ADC's. The effectiveness of the proposed definition is compared with that of other proposed definitions over a range of signal amplitudes and noise levels.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Tamás Zoltán Bilau, Tamás Megyeri, Attila Sárhegyi, János Márkus, István Kollár
FOUR PARAMETER FITTING OF SINE WAVE TESTING RESULTS: ITERATION AND CONVERGENCE
Small improvements to the iteration procedure of the IEEE Standard 1241-2001 are suggested, and extension of the standard MATLAB program implementing the sine wave test is discussed. The program is compatible with the LabView program already announced, and in other working modes offers extensions, too.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Marek Kurkowski, Pawel Ptak, Zygmunt Biernacki, Tadeusz Zloto
ACCURACY OF SIGNAL CONVERSION IN POWER MEASUREMENTS WITH LEM CONVERTERS
Among the phenomena significantly aggravating the quality of electric energy in the grid two are especially important: voltage fluctuations and deformations of voltage and current sinusoids.
The aim of the study described in the present paper was to improve the accuracy of signal converting in power measurements in non-linear receivers. The measurements of voltage and current were performed by means of a PC with measuring a card PCL-818L and with application software DasyLab 6.0 enabling the registration and converting of signals.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Marek Kurkowski, Zygmunt Biernacki, Tadeusz Zloto, Pawel Ptak
SIGNAL GENERATION AND ACQUISITION IN THE CORRELATION WTS
The paper deals with problems of signal analysis. Examples of system modelling by means of Dasylab package are discussed.
Measurements, analysis and visual presentation of selected signals were performed by means of measuring card PCL818 and Dasylab package. They are also described in the present paper [7].
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Tadeusz Zloto, Zygmunt Biernacki, Marek Kurkowski, Pawel Ptak
COMPUTER-AIDED SYSTEM FOR MEASURING TEMPERATURE OF ROTATING ELEMENTS
The paper includes a review of currently used devices for measuring temperature of rotating parts of machines. In the subsequent section it describes a computeraided measuring system developed by the authors. Using the optoelectronic measuring path, the system is employed for measuring temperature of cylinder block of an axial multipiston pump.
Besides, the application of DasyLab software package for the above mentioned measurements is presented.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Mustafa Keskin, Matthew E. Brown, Un-Ku Moonm, Gábor C. Temes
A VOLTAGE-MODE SWITCHED-CAPACITOR BANDPASS ΔΣ MODULATOR
A novel fourth-order voltage-mode switched-capacitor bandpass ΔΣ modulator, using direct-charge-transfer pseudo-N-path resonators, is described. This modulator is insensitive to component mismatches and finite opamp bandwidth, and is also less sensitive to finite opamp gain than previous bandpass ΔΣ data converters. It is therefore suitable for high-speed communications applications.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
F. Adamo, F. Attivissimo, N. Giaquinto
MATLAB TOOLBOXES FOR A/D CONVERTERS CHARACTERIZATION
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
J.J. Ocampo Hidalgo, A. Garcia Ortiz, L. D. Kabulepa, M. Glesner
ANALYSIS AND DESIGN OF A 4th ORDER BANDPASS SIGMA DELTA MODULATOR FOR GSM COMMUNICATIONS STANDARD
This work addresses the design of a 4th order bandpass sigma delta modulator (BPSDM) for IF AD converters suitable for second generation cellular standards such as GSM. The resonator architecture of a BPSDM can be derived from the transfer characteristic of a lowpass modulator by means of mathematical transformations. It can be observed that each transformation results in a different cascade of resonators (COR). Therefore different values of performance metrics like SNR, dynamic range, robustness against circuit non-idealities and SFDR can be expected. Behavioral simulations at the architectural level were carried out to find the COR that best meets the requirements imposed by the GSM communications standard and minimizes requirements of the sub-circuits used in the chosen architecture. A BPSDM was designed and sent to fabrication, using a 0.3 µm, double polysilicon, triple metal, N-well CMOS technology. Simulation results are showing that the proposed prototype reaches a SNR of 85 dB and a sampling rate of 80 MHz.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Milan Štork
MODIFIED Σ-Δ VOLTAGE TO FREQUENCY CONVERTER
Voltage to frequency converter (VFC) is an oscillator whose frequency is linearly proportional to control voltage. There are two common VFC architectures: the current steering multivibrator and the charge-balance VFC. For higher linearity, the charge-balancing method is preferred. The charge balanced VFC may be made in asynchronous or synchronous (clocked) forms. The synchronous charge balanced VFC or "sigma delta" (Σ-Δ) VFC is used when output pulses are synchronized to a clock. The charge balance VFC is more complex, more demanding in its supply voltage and current requirements, and more accurate. It is capable of 16 to 18 bit linearity.
Σ-Δ modulator can be used for synchronous VFC (SVFC). The synchronous behaviour is good in many applications, but the output of SVFC is not a pure tone (plus harmonics) like a conventional VFC, but it contains components harmonically related to the clock frequency. The SVFC produces a change in probability density of output pulses N and N+1 clock cycles after the previous output pulse.
In this paper, the modified SVFC (MSVFC) is described. This MSVFC works similarly as conventional SVFC but it has a pure tone on output (for constant input voltage). Therefore, it is possible to measure the period of MSVFC output (this does not work for SVFC).
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
R. Kochan, A. Sachenko, V. Kochan, N. Vasylkiv
UNIVERSAL SIGMA-DELTA ADC FOR INTELLIGENT DISTRIBUTED INSTRUMENTATION
In this papers the precision single-board, 8 channels, 24 bit sigma-delta ADC with on-line remote reprogramming mode is described. The results of experimental researches of the noise immunity of the developed ADC in real (industrial) measurement conditions are presented. The results of experimental researches of the prototype in the same measurement conditions are also considered.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
E. Garnier, A. Tetelin, Ph. Marchegay
CANCELLATION OF CHARGE INJECTION ERROR ON SWITCHED CURRENT DIVIDER CIRCUITS FOR ACCURATE D/A CONVERTERS
This paper proposes compensated methods to cancel the effects of charge injection error on switched-current Divider Circuits. Algorithmic structures of current dividers are presented and the final charge injection error is evaluated for each Algorithm. So, compensated methods to cancel this error are proposed.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Daniel Belega
SYSTEM FOR TESTING ANALOG-TO-DIGITAL CONVERTERS
This paper presents a system named "ADC TEST" that estimates the static and dynamic parameters of an analog-to-digital converter according to the definitions given in IEEE Standard 1241. One shows the available output graphical pages with theirs information and facilities in a practical testing application.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Vadim Geurkov
A BUILT-IN SELF-CHECK METHOD FOR MULTI-CHANNEL MEASUREMENT SYSTEMS
Signature analysis techniques have become extremely popular in digital systems testing due to such advantages as simplicity, small amount of additional circuitry, and small degree of error masking. In this paper the signature analysis techniques are applied to mixed (analog-to-digital) systems testing. The general case of multi-channel measurement system is considered.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Stanislav Ďaďo, David Slepička
ADC TESTING BASED ON FREQUENCY ESTIMATION
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Ján Šaliga, Szabolc Csernok
C-LANGUAGE FUNCTION CLASS FOR SIGNAL PROCESSING AT ADC TESTING
The paper presents some ideas and results from the attempt to create a comprehensive suite of data processing, C-language functions that enables simplifying the development of new, user oriented software for testing analog to digital converters according the IEEE standards 1057, 1241 and DYNAD. The developed function class covers both dynamic and histogram based test methods. Nowadays, it is prepared in the form of instrument driver - function panel (*.fp) for the software development package Lab Windows⁄CVI by National Instruments. All functions were developed, debugged and tested in this environment.
The paper also contains some results from comparing the new developed function class used in a developed examples of end-user applications with test data processing Matlab software by Kollar and Markus.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
U. Frühauf, E.-G. Kranz, H. Leuterer
DEMONSTRATOR FOR RESOLUTION INCREASE AND AUTO-CORRECTION IN EMBEDDED MEASUREMENT SYSTEMS
For investigation and training of students in the field of high resolution measurement technology was built an embedded measurement system with 16 bit resolution and additional modules for self-diagnostics and autocorrection, including a monitoring measurement system for evaluation.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Matteo Parenti, Andrea Boni, Davide Vescovi
A 6-b 1Gsample/s SiGe BiCMOS A/D Converter
The paper describes the design of a 1GS/s 6-bit ADC in SiGe BiCMOS technology. Several techniques such as subranging, interpolation and averaging were implemented on the original flash architecture in order to achieve low power consumption without sacrificing linearity and dynamic performance.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Jan Fischer, Jan Vejdelek
REAL-TIME CORRECTION OF DC OFFSET OF LOW-COST AUDIO CODECS IN ACOUSTIC DIGITAL LOCK-IN AMPLIFIERS
In design of the DSP for acoustic applications it is appropriate to integrate a low-cost audio codec into their structure. Audio stereo codecs are able to achieve a high resolution of measurement on low frequencies of the input signal. But audio codecs are able to digitalize only signals of the acoustic origin, it means the signal without the DC part of frequency spectrum. In the majority of available DSP there are 2 independent AD converters and also 2 DA converters. But most of audio codecs create the DC offset during the conversion to the digital form, it means 0V voltage amplitude of input signal doesn’t correspond to 0HEX in hexadecimal form of output digital word. The solution how to achieve the required parameters with these low-cost audio codecs is founded in this project.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
A.A. Platonov, K. Jędrzejewski, J. Jasnos
MATHEMATICAL AND COMPUTER MODELS IN MULTI-PASS ADC DESIGN AND OPTIMISATION
The paper presents a mathematically grounded approach to the analysis and optimisation of multi-pass analogue-to-digital converters (MADCs) with the algorithmic forming the estimates of converted samples. The approach enables a comprehensive analysis of the converter work using a virtual model of MADC built on the basis of its mathematical model. This model is based on the extended optimal identification algorithms adapted to the particularities of A/D conversion. The obtained sub-optimal algorithms take into account all main parameters of the internal auxiliary ADC and other analogue elements of MADC. The results of advanced simulations confirm a full agreement of theoretical and experimental evaluations, as well as efficiency of the proposed approach as a tool for MADC design support.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Zygmunt Biernacki, Tadeusz Zloto, Marek Kurkowski, Pawel Ptak
ANALYSIS OF ACCURACY AND MEASUREMENTS OF FLOWING MEDIUM PARAMETERS BY MEANS OF A WAVE THERMOANEMOMETER SYSTEM
The paper analyses the measurement accuracy of selected parameters, such as flow velocity and temperature, of a flowing medium, by means of the thermoanemometric method. The core of the method relies on the Wave Thermoanemometer System constructed by one of the authors. The sources of boundary error components are analysed within the signal conversion channels of the WTS. Errors are examined by means of relevant mathematical expressions representing signal conversion both in the velocity measuring channel and in temperature measuring channel. The algorithms have been developed for perfect and for real conditions. The theoretical considerations have been verified by laboratory tests performed by computerized equipment.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
J. Roztocil, D. Varga, M. Siroky
ASPECTS OF LOW DISTORTION SINE WAVE GENERATORS MEASUREMENT
This paper deals with testing of ultra-low distortion sine wave generators. Measurement of harmonic distortion based on lock-in amplifiers is described and practical results using fundamental-suppression method are presented.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Vasili K. Semenov
SUPERCONDUCTOR ADCS BASED ON PROCESSING OF SINGLE FLUX QUANTA
Superconductor ADCs exist and their performance is quickly approaching to those of the best semiconductor counterparts. Deep cooling could complicate a broad spreading of the still exotic superconductor technology. However, the technology is highly attractive for invention or at least numerical simulations of novel conversion schemes.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
T.H. Pearce
ADC DYNAMIC RANGE IMPROVEMENT FOR WIDEBAND HF RECEIVERS
The development of 14 bit monolithic Analogue to Digital Converters (ADC’s) capable of sampling at 80 MHz has revived interest in digitising the entire 3-30 MHz High Frequency (HF) radio spectrum for use in wideband HF receivers. This enables the ADC to be placed close to the antenna so removing the need for analogue mixing as well as offering a multi-channel reception capability, using multiple digital synthesisers and direct conversion I, Q mixing to baseband ...
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
John Pickering
DEVELOPING THE SIGMA-DELTA A-D FOR PRECISION DC&LF METROLOGY
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Alan J. Davies, Godi Fischer, Hans-Helge Albrecht, Jürgen Hess
IMPROVED NULL CANCELLATION IN A 6th-ORDER Σ-Δ MODULATOR REALIZED WITH TWO 3rd-ORDER SECTIONS
This paper presents an improved rnethod to digitally correct for statit, analog circuit imnperfections in a two-stage, 6th order, cascaded (6-3) sigma-delta modulator. By adding a digital correction term to the output of die digital noise cancellation filter, the first stage parasitic quantization noise due to finite amplifier gain and C-Ratio mismatches can be completely removed. A 6-3 modulator implemented as a fully differential switched-capacitor circuit, designed for an OSR of 16, has heen fabricated in a 1.2 µm double-poly n-well CMOS process. Improvements have been made in the null cancellation leading to approximately a 10 dB increase in SNDR ovor a range of signal amplitudes from 12 µVolts to 500 mV. A peak SNDR/SFDR of 87/100 dB for a 1 MHz sample rate and 84/93 dB for a 2.5 MHz sample rate have heen achieved.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
János Márkus, Gábor C. Temes
AN EFFICIENT ΔΣ NOISE-SHAPING ARCHITECTURE FOR WIDEBAND APPLICATIONS
In this paper a new optimized multi-stage ΔΣ (Delta-Sigma) structure is proposed. The method combines the reduced-sample-rate architecture with the optimization of the zeros of the noise transfer function (NTF). To achieve this, the first stage of the decimation filter has to be modified as well. Applying this method one can avoid the SNR loss introduced by using the reduced-sample-rate second-stage. The SNR can actually increase for higher-order structures. Simulation results for a 2-0 MASH structure with an oversampling ratio of 4 are shown to verify the technique.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
X. Wang, U. Moon, G. C.Temes
DIGITAL CORRELATION TECHNIQUE FOR THE ESTIMATION AND CORRECTION OF DAC ERRORS IN MULTIBIT MASH ΔΣ ADCS
A fully digital algorithm is described for acquiring and correcting the errors of the feedback DAC used in a multibit ΔΣ MASH ADC. The method operates in the background and is highly accurate. It is particularly useful for wideband ADCs, where mismatch error shaping becomes ineffective. Combined with an improved digital adaptive compensation technique, which greatly reduces the raw quantization leakage in MASH architecture, it makes the design of fast and accurate ADCs using inaccurate components possible.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
D. Macii, P. Carbone, D. Petri
STABILITY ANALYSIS OF OSCILLATORS BASED ON A DELTA–SIGMA TOPOLOGY
The growing demand of mixed–signal integrated circuits encourages the research of Built-In Self-Test (BIST) techniques to achieve simpler and less expensive testing processes. High quality sinusoidal oscillators based on a Δ-Σ topology are an effective solution to perform the test of this kind of devices. Unfortunately, due to the in–loop 1–bit quantizer nonlinearity, several problems of stability have been observed. A stability analysis on the behavior of the oscillator based on a second order Δ-Σ modulator presented in [1] is described in this paper. In particular, it is shown that the oscillator is intrinsically unstable and its complete dynamics is very difficult to predict exactly. Finally, a possible stabilization strategy is proposed.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
A. Moschitta, D. Petri
EFFECTS OF ADC INTEGRAL NON-LINEARITY ON DIGITAL TRANSMISSION
This paper investigates the effects of Integral Non-Linearity (INL) on the performances of both A/D converters and Digital Communication Systems, which exploit Direct Digital Modulation. The performances of both PCM and Sigma-Delta converters affected by INL are considered and compared. Then, the effects of INL upon the BER performances of an OFDM system are evaluated and modeled. The accuracy of the theoretical model is discussed with respect to the ADC resolution and INL levels. It is shown that a multibit Sigma-Delta converter, operating at a low oversampling ratio, may outperform PCM converters.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
R.K. Kamat, G.M. Naik
ANALOGUE TO DIGITAL CONVERTER WITH NON-LINEAR TRANSFER FUNCTION FOR THERMISTOR APPLICATIONS
There exists a disproportionate difference between dynamic range, resolution, and accuracy when the output of sensors having nonlinear characteristics like thermistors are digitized with the conventional linear ADCs. There are several methods to linearise the thermistor characteristics but at the expense of hardware, memory and time efficiency. This paper presents a new simple method of shaping the transfer function of a pulse width modulation ADC as per the thermistor characteristics. It is based on the principle of varying the amplitude of the reference voltage to reach the temperature equivalence of voltage being digitized.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
K. Ola Andersson, Niklas U. Andersson, Mark Vesterbacka, J. Jacob Wikner
COMBINING DACS FOR IMPROVED PERFORMANCE
This work is an overview of recently proposed methods on combining DACs in order to improve performance. Some further development of these techniques are also presented. The techniques aim at reducing glitches and sensitivity towards limited output impedance in current sources.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Mark Vesterbacka, K. Ola Andersson, Niklas U. Andersson, J. Jacob Wikner
USING DIFFERENT WEIGHTS IN DACs
In this paper we discuss some properties of different codes with their respective sets of weights to be used in digital-to-analog converters (DACs). The thermometer (unratioed) code is widely used instead of a binary code in the most significant bits of a segmented DAC to reduce errors due to weight and timing mismatch. The binary and thermometer codes are two extremes, where the first offers a small digital hardware cost and the latter a large cost. We have investigated some of the properties of these codes and codes with properties in-between; such as linear, polynomial, and segmented codes. Some new ideas and results on using different sets of weights and how to generate them are presented. We present simulation results for some low-order polynomial codes.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
I. Vecera, R. Vrba
NOVEL PIPELINED SWITCHED-CURRENT A/D CONVERTER FOR SMART SENSORS
This paper describes pipelined switched-current A/D converter designed in 0.6 µm BiCMOS technology. Modified conventional-restoring algorithm, called redundant-sign-digit (RSD), was implemented what decreases the amount of high-precision components. Two modes of operation are possible. By changing from pipeline conversion to cycling mode, less power dissipation is obtained at the expense of conversion time. Proposed A/D converter is suitable for conversion of the current with very low amplitude from analog into digital domain. Current mode enables operation down to 3 V thus is suitable for battery powered applications. The system integrates band-gap reference and independent supervisory circuit with 1% accuracy. Current consumption in sleep mode is less than 1 mA. A/D converter is prepared to meet 1452.2 specifications.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Alberto Die, Maurizio Valle
EVALUATION OF TIME RESOLUTION OF NMOS SAMPLING SWITCHES
Usually in CMOS line receivers and downconversion mixers, a key component is the NMOS sampling switch. When designing sampling switches, one has usually to trade off resolution against bandwidth and aperture time. In this perspective, we modeled the aperture time of the NMOS sampling switch for low swing voltage signals taking also into account the dependence of the threshold voltage on the body effect. Then we compared the aperture time behaviour using three submicron CMOS technologies (0.8, 0.5 and 0.25 μm minimum channel length respectively). The results indicate that an aperture time of about 100 ps is achievable with a CMOS 0.25 μm minimum channel length technology working at low supply voltage.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Reinhard Kindt, Richard Ižák
AN ANALOG APPROACH TO COMPENSATE FOR OpAmp OFFSET AND FINITE GAIN IN SC CIRCUITRY: A CASE STUDY OF A CYCLIC RSD ADC
Design of high-resolution Nyquist rate A/D converter necessitates the usage of advanced circuit techniques to compensate for arising analog errors. In switched capacitor ADC, besides the well know techniques such as bottom plate sampling, mismatch-independent and redundant (RSD: 1.5 bit/stage) conversion for the elimination of charge injection, capacitor mismatch, comparator and offset sensitivity, respectively, the most utilised circuit techniques are those for OpAmp’s offset and finite gain errors cancellation. An alternative technique for compensation of the errors due to finite gain and offset of Opamp in SC circuits is proposed. This novel method features a charge addition and is compared to so far used approaches based on voltage addition. The concept and the results of a 5 V CMOS implementation of cyclic RSD ADC with ratio-independent SC technique using this correction method are discussed.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
G.C. Cardarilli, A. Del Re, R. Lojacono, A. Nannarelli, M. Re
PERFORMANCE COMPARISON BETWEEN TRADITIONAL AND RNS-BASED ADC
Recently a new architecture for an analog to Residue Number System converter was proposed by the authors. In this paper a comparison of the performances, in terms of probability of LSB error due to internal noise, between a traditional ADC converter and this said analog to RNS converter is given.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Olli Vainio
ADAPTIVE SCHEME FOR OVERSAMPLED FRONT ENDS
A computationally efficient adaptive filtering scheme for oversampled A/D converters is discussed. The decimating digital filter is constructed as a combination of a sinc decimator and an adaptive predictor. A reduced-rank adaptive algorithm with two adaptive parameters is proposed for this purpose avoiding the complexity of the commonly used full-rank algorithms. The characteristics of the adaptive filter are considered, and a comparative example of data signal processing is shown.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Ivo Viščor, Josef Halámek
ACQUISITION SYSTEM WITH LOW JITTER
The high dynamic range system is often limited by the jitter. The sources of the jitter are the clock generator, the clock distribution and the ADC. Two different methods of the ADC jitter measurement are presented.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Carsten Wegener, Michael Peter Kennedy
TESTING ADCs FOR STATIC AND DYNAMIC NONLINEARITIES - KILLING TWO BIRDS WITH ONE STONE
Traditionally, static linearity and dynamic distortion tests are performed separately for ADCs. To this end, a low-frequency sinewave is histogrammed to measure static Integral Nonlinearity, and a high-frequency sine-wave is sampled for FFT processing to measure dynamic distortions and dynamic range.
We propose to use a model-based technique to extract both static and dynamic nonlinearities from a single data record of a sampled high-frequency sine-wave. This saves test time as the ADC converts fewer samples.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
J. Halámek, I. Višèor, M. Kasal, M. Villa, P. Cofrancesco
HARMONIC DISTORTION AND STATISTICAL ANALYSIS
The measurement of harmonics terms on two identical digital receivers with fast ADC (AD6644) is presented and statistically analyzed. The results are discussed according to the origin of harmonics and difference between spurious and harmonics.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
M. Comte, F. Azaïs, S. Bernard, Y. Bertrand, M. Renovell
ON THE EVALUATION OF ADC STATIC PARAMETERS THROUGH DYNAMIC TESTING
Full characterization of ADC requires both a histogram-based approach and a spectral analysis to determine respectively static and dynamic parameters. This paper investigates whether static performances can be extracted from spectral analysis, in order to develop a low-cost test procedure. Results show that under appropriate test conditions, the dynamic parameters extracted from a classical FFT exhibit significant variations against ADC offset and gain errors.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
Roland Holcer, Linus Michaeli
TESTING DNL AND INL OF ADC BY THE EXPONENTIAL SHAPED VOLTAGE
Testing of ADC’s differential nonlinearity DNL(k) by the histogram method requires the signal generator with extremely low distortion and high stability of the parameters. Besides this condition generator must be connected to the input of the ADC under test with high suppression of the interfering noise on ground line of instruments. The new type of testing signal has been proposed of the exponential form which could be generated by discharging of the capacitor across the resistance. The acquired digital samples from the output of ADC under test allow determining the best fitted exponential signal. The histogram from the registered samples and that for the best fitted exponential shape allows determining the differential nonlinearity DNL(k) for any code level k. Practical problems with generating the pure exponential shape are shown in this paper. The proposed method has been experimentally verified and was compared with the standardized methods.
4th Conference on Advanced A/D and D/A Conversion Techniques and their Applications and 7th Workshop on ADC Modelling and Testing, Prague, Czech Republic, 2002
V. Vasauskas
DYNAMIC HARDNESS DURING DIFFERENT PHASES OF INDENTATION
The paper reports on the underlying concept for securing the measuring basis used in the method of dynamic hardness which employes one of the standard indentation methods and various shapes of indenter. The complete dynamic indentation cycle can be divided into the three following phases: starting phase, indentation phase and rebound phase. The value for several engineering metals obtained dynamic hardness in various phases of indentation was 1.12 – 1.40 higher than the static hardness.
11th Conference on Hardness Measurement, Celle, Germany, 2002
H. Yamamoto, T. Yamamoto, H. Kawashima, S. Sudoh
HARDNESS TRACEABILITY SYSTEM
As a matter of fact, global standards for hardness testing are set by International Organization for Standardization. The ISO standard for hardness testing consists of three parts: Part 1 is for test methods, Part 2 is for testing machines, and Part 3 is for hardness standard blocks. JIS provides three independent standards, but they have perfect consistency with the three parts of the ISO hardness-testing standard. These standards prescribe that hardness testing machines first be subject to direct verification of their test force, indenter, testing cycle, and hardness indicator, and then that hardness must actually be measured using standardized blocks for indirect verification. This is a globally agreed fact. In this connection, the traceability or the uncertainty of Rockwell hardness has been a topic of international debate. This paper discusses our position on this issue as a manufacturer of hardness standardized blocks.
11th Conference on Hardness Measurement, Celle, Germany, 2002
D. Schwenk
VARIATION OF THE CALIBRATING VALUE AND THE RANGE DEPENDING ON THE NUMBER OF THE CALIBRATING INDENTATIONS DURING THE ROCKWELL HARDNESS TEST
Represented is the problem at the definition of measure values in the standards from the statistical point of view. The definition of the calibrating of hardness reference blocks in the standards will be translated to a statistical model formulations. The statistical model will be checked by experimental measurements. The problem of the determination of a quality feature for the hardness reference blocks will be discussed.
11th Conference on Hardness Measurement, Celle, Germany, 2002
R. Affri, G. Barbato, S. Desogus, A. Germak, C. Origilia, D. Perteghella
METROLOGICAL CHARACTERIZATION OF OPTICAL MEASURING SYSTEM FOR HARDNESS INDENTERS
The verification of the geometry of Rockwell indenters has been widely studied in the past and, at the present, it is one of the most important tasks (in the uncertainty budget of hardness measurements) in discussion in many international organizations involved in the hardness field. The new measuring system designed in IMGC and developed in cooperation with AFFRI has been characterized and the results of the calibration are presented. The uncertainty evaluation has been calculated following the ISO guide on uncertainty evaluation. At the end, the results of the intercomparison between the new instrument and the instrument used up to now in IMGC laboratory, completely different from the point of view of measurement methodology, are presented.
11th Conference on Hardness Measurement, Celle, Germany, 2002
A. Stibler, K. Herrmann, Th. Polzin, A. Germak
COMPARISON MEASUREMENTS OF HARDNESS SCALES FOR ESTABLISHING THE HARDNESS STANDARD OF SLOVENIA
A commercial hardness testing machine was provided to represent a hardness reference standard in Slovenia. In order to evaluate how accurate the hardness scales realised with this machine could be, the main influence factors contributing to the uncertainties were verified and comparative measurements carried out, the results of which were compared with several laboratories owning primary hardness standard machines.
11th Conference on Hardness Measurement, Celle, Germany, 2002
A. Wehrstedt
SITUATION OF STANDARDIZATION IN THE FIELD OF MECHANICAL TESTING AND MEASUREMENTS
Standardized mechanical test methods are referred in many materials and product standards for the characterization of quality of the materials or products. Mechanical testing is carried out on materials for three different reasons: - For quality control purposes to ensure that a material conforms to a technical specification or that it has been correctly processed. - To provide information which can be used in the design of a component or structure. - As part of investigations into the reasons for failures in service. Hence the results achieved from the mechanical testing of products that are made of / or from materials are used to help guarantee the safety and reliability of materials which in turn ensures the safety of those products. The paper gives an overview on the standardization activities of the last ten years for the different fields of mechanical testing as uniaxial, ductility, hardness, toughness and fatigue testing .
11th Conference on Hardness Measurement, Celle, Germany, 2002
N. Huber, E. Tioulioukovsski
SMART INDENTATION METHODS: THE APPLICATION OF NEURAL NETWORKS
In the last decade, the nanoindentation technique has become one of the most important characterization methods in micro dimensions. The experimental and analytical techniques have been pushed towards an identification method that can compete with tensile tests. It is self-evident to apply these powerful tools in macro dimensions as well, where the nanoindentation technique has its roots. In this paper a new method is presented how the true stress-strain curve as well as the viscosity and creep behaviour of a given material can be extracted from the indentation curve by using a smart analysis tool based on neural networks. Finite Element simulations are carried out for randomly chosen sets of material parameters and maximum indentation depth. The resulting load-depth and depth-time curves are collected in a database together with the material parameters. With this database neural networks are trained to identify the material parameters from measured load-depth and depth-time curves.
11th Conference on Hardness Measurement, Celle, Germany, 2002
F. Loeffler (F. Löffler), A. Sawla, P. Strobel
CALIBRATION OF THE DEPTH-MEASURING DEVICE OF ROCKWELL HARDNESS TESTING MACHINES
In addition to the indirect verification using reference blocks and a reference indenter, it is possible to realise the calibration by direct verification of the test force, the indenter, the depth-measuring device and the testing cycle. Some conditions of the calibration process, e.g. the verification range, and the necessary accuracy of the depth-measuring device are described in standard ISO 6508-2. With reference to these parameters, a new depthmeasuring calibration device was developed. The study describes the function of this device and the calibration process. The advantages of this new process are that the measurement takes place in the axis of force application and that the calibration is independent of the Rockwell hardness scales. During calibration, the force stresses the calibration device but not the sensitive measuring sensor. Results of a real depth-measuring device verification are also presented.tion process. The advantages of this new process are that the measurement takes place in the axis of force application and that the calibration is independent of the Rockwell hardness scales. During calibration, the force stresses the calibration device but not the sensitive measuring sensor. Results of a real depth-measuring device verification are also presented.
11th Conference on Hardness Measurement, Celle, Germany, 2002
M. Griepentrog, Ch. Ullner, A. Dueck (A. Dück)
INSTRUMENTED INDENTATION TEST FOR HARDNESS AND MATERIALS PARAMETER FROM MILLINEWTONS TO KILONEWTONS
The ISO/DIS 14577 Metallic materials - Instrumented indentation test for hardness and materials parameters – Part 1-3 (IIT) concerns test forces up to 30 kN. The paper reports on IIT at test forces ranging from 0.002 N to 1000 N on non – magnetizable steel X8 CrMnN 18- 18 (1.386) with well polished surface using Vickers indenter and four hardness machines of different design (Nano Indenter XP, Fischerscope H 100, Zwick Z005 with Universal hardness head and a laboratory four-column set up materials testing machine) according to the standard. Using mostly identical test parameters the results of the different machines are almost in good agreement. Estimated small differences are caused by the different uncertainties of the used machines and by different methods of mathematical analysis of the detected raw data.
11th Conference on Hardness Measurement, Celle, Germany, 2002
Ch. Ullner, Th. Reich
STUDY ON THE CAPABILITY OF MATERIALS AS REFERENCE BLOCKS FOR THE MACRO RANGE OF INSTRUMENTED INDENTATION TEST
Part 3 of the ISO 14577 “Instrumented indentation test for hardness and materials parameters“ (IIT) concerns the calibration of reference blocks. Besides the widely spread activities for supplying reference blocks in the nano and micro range it is needed to be taken into account the macro range too. The paper reports on test results on ceramic materials which are tailored for reference blocks. The specimens made of Si3N4, SiC, or Al2O3 ceramics are highly homogenous and exhibit an increased quality with a roughness Ra ≤ 0.005 µm. They are successfully used for reference blocks of the traditional Vickers and Knoop hardness. In comparison, the capability of hardened steel which is used for traditional hardness techniques is studied.
11th Conference on Hardness Measurement, Celle, Germany, 2002
Th. Choudoba, M. Griepentrog, U. Beck
COMPARISON BETWEEN VICKERS HARDNESS AND INDENTATION HARDNESS
The Vickers hardness is an often used hardness definition, mainly in the force range above 0.5 N. With decreasing film thickness and the need of lower loads, depth and force sensing measurement techniques became more and more important and a new indentation hardness was introduced, finally resulting in the international standard ISO 14577. Therefore investigations regarding the comparability of both hardness definitions are of high interest. In principle it should be possible to obtain the same hardness number with both measurement methods if the true contact area can be determined. The agreement is checked for a large selection of materials and instruments for a force of 0.5 N (HV0.051). The calculation of the correct contact area from depth sensing measurements is also checked by a comparison of the indentation modulus with the Young’s modulus, obtained with other methods.
11th Conference on Hardness Measurement, Celle, Germany, 2002
A. Liguori, A. Germak, G. Gori, E. Messina
GALINDENT: THE REFERENCE METROLOGICAL SYSTEMS FOR THE VERIFICATION OF THE GEOMETRICAL CHARACTERISTICS OF ROCKWELL AND VICKERS DIAMOND INDENTERS
The paper describes the GALINDENT system that LTF – Galileo Hardness Testing Department, in co-operation with the Institute of Metrology "G. Colonnetti", has developed for the geometrical verification of Rockwell, Vickers diamond indenters, as prescribed by ISO Standards. This system consists of two instruments: an Interferometric Sine-Bar, for angular, straightness and flatness measures and a Rotary Table, for the verification of the spherical tip of Rockwell indenters. These two devices can be set up in one workstation, interfaced with the same computer for data analysis. A software package has been specifically developed to manage the entire system. The measurement test cycle is completely automated in order to ensure objective and reliable results. The operator interface, based on a graphic window menu in the Windows® environment, is extremely user friendly and it does not require any programming knowledge.
11th Conference on Hardness Measurement, Celle, Germany, 2002
G. Barbato, G. Brondino, M. Galetto, G. Vicario
'ZERO POINT' IN THE EVALUATION OF MARTENS HARDNESS UNCERTAINTY
The Instrumented Indentation Test is based on simultaneous recording of force and indentation depth, obtained during test cycle. The force-depth curve, describing the indentation pattern, is typically formed by two parts having the “zero-point” in common, i.e. the first contact point between the indenter and the surface of test piece. The zero-point determination is a crucial aspect for Martens Hardness evaluation, so that relevant ISO standard suggests to estimate it by extrapolation of polynomial fitted functions. In this paper a new model, based on a segmented function, is proposed. This approach implies the use of maximum likelihood estimator for parameters determination. The corresponding uncertainty is provided through the covariance matrix of the regression model.
11th Conference on Hardness Measurement, Celle, Germany, 2002
S.R. Low
AN EMPIRICAL APPROACH TO DETERMINING ROCKWELL HARDNESS MEASUREMENT UNCERTAINTY
Characteristics of the empirically developed Rockwell hardness test make it difficult to determine measurement uncertainty using methods based on mathematical models describing the relationship between the measurand and the influence quantities. An empirical approach to determining Rockwell hardness uncertainty has been developed, which provides a method based on the familiar procedures and practices of Rockwell hardness testing laboratories. The approach views the hardness machine and indenter as a single measuring device, and considers uncertainties associated with the machine repeatability and the usage of the machine over time with varying environmental conditions and with different operators. The approach also considers the measurement bias of the Rockwell hardness machine as compared to reference standards.
11th Conference on Hardness Measurement, Celle, Germany, 2002
A.C. Vidal, A.R. Martins, I.M.V. Caminha, A. da Cunha Rocha, S.P. Oliveira
THE INFLUENCE OF THICKNESS ON THE NON UNIFORMITY VALUES OF ROCKWELL B HARDNESS STANDARD BLOCKS
In the present work, the influence of thickness variation and of the microstructural aspects on the hardness uniformity of Rockwell B standard blocks is discussed. In order to correlate the results, two different heat treatments were performed on the steel employed to manufacture the standard blocks. Three different thickness ranges were studied for each of the two heat treatments conditions applied to the standard blocks material. The microstructural characteristics were studied by means of optical microscopy. The hardness measurements were carried out in hardness testing machines belonging to the three Brazilian Institutes involved in the present study. The results indicate that the non-uniformity hardness values are directly affected by the resulting microstructural changes due to the applied heat treatments. However, a relationship between thickness variation and hardness values has not yet been entirely understood.
11th Conference on Hardness Measurement, Celle, Germany, 2002
J. Song, S. Low, L. Ma
TOLERANCING FORM DEVIATIONS FOR ROCKWELL DIAMOND INDENTERS
The form deviations of Rockwell diamond indenters can cause significant differences in Rockwell hardness readings. In order to control that effect, tolerances for form error deviations of Rockwell diamond indenters have been specified in both the American Society of Testing and Materials (ASTM) and the International Organization for Standardization (ISO) standards. In this paper, experimental data on the effects of form deviations of Rockwell indenters are analyzed. Finite Element Analysis (FEA) is used to simulate the effect of form deviations on HRC readings. Theoretical analyses are verified by experimental results. Based on these results, as manufacturing and measurement techniques for Rockwell diamond indenters improve, it is suggested that a tighter tolerance be specified for the form deviations of Rockwell indenters used for calibrations of reference blocks.
11th Conference on Hardness Measurement, Celle, Germany, 2002
M. Tsujii, F. Koshimizu, E. Furuta, K. Kojima, H. Hayashi, H. Ishida
DEVELOPMENT AND PERFORMANCE OF HARDNESS TESTING MACHINE CALIBRATION PROCESSOR
The calibration device capable of performing direct verification of both test force & indentation depth, which are fundamental elements of a Rockwell type hardness tester, was developed. This device can also carry out verification of operating conditions. In this paper, the examples of uncertainty of hardness calculated, based on uncertainty of each element, using this device are shown and the calibration results on the conventional testing machine calibrated by the standardized Rockwell hardness testing machine, which has been used at Akashi Corp., are also shown.
11th Conference on Hardness Measurement, Celle, Germany, 2002
K. Hattori, S. Takagi, Y. Seino, H. Nakano
DISPLACEMENT MEASUREMENT OF AN INDENTATION TESTER USING HETERODYNE INTERFEROMETER
We have developed an heterodyne laser interferometer system to measure the indenter displacement of instrumented indentation at nano-/micro- ranges. The developed interferometer was applied to measure the displacement of an commercial type indentation tester. The interferometer system and the tester was set on the different anti-vibration systems. So the main difficulty of this measurement was how to got rid of the relative vibration effect. We designed the system as that the reference points of the system is set to the displacement measurement mirrors on the testers. The total stability of the displacement measurement system was about 10 nm in spite of the larger amplitude of the relative vibration, which is larger than the 1 mm. We can successfully measure the indenter displacement by using newly designed interferometer system and is compared the displacement signal obtained from the tester.
11th Conference on Hardness Measurement, Celle, Germany, 2002
S. Tagaki, K. Hattori, Y. Seino, H. Nakano
ESTIMATION OF EFFECTS OF INDENTER-TIP GEOMETRY BY MEANS OF FINITE ELEMENT ANALYSIS OF NANO-INDENTATION
To investigate the influence of geometric error of indenter tip in nano-indentation test, direct measurement of indenters and analyses of indentation process are carried out. Geometry of indenter tip is measured with a scanning probe microscope and geometrical parameters such as face angles, tip radius and truncation length are calculated. Based on these results, the models for the finite element analyses are created. Analyses of indentation processes into a metal sample are carried out and the influence of tip geometry is discussed.
11th Conference on Hardness Measurement, Celle, Germany, 2002
P. Neumaier, G. Michalzik
MECHANICAL CHARACTERIZATION OF MATERIAL COATINGS USING THE FISCHERSCOPE H100 (R) COMPACT
The load/indentation depth method has received broad acceptance both in quality control and in research and product development for characterizing the mechanical behavior of thin coatings and also of small and smallest material areas. Continuous high-resolution recording of test load and indentation depth for the full test cycle (loading and unloading) is used in a variety of ways in particular for test loads in the microhardness range. Contributing factors to its acceptance were the greater information content of the measurement results, the operator-independent test procedure and the speedy standardization of the test method. However, until now, the use of the instrumented indentation test has been limited to relatively small specimens or required the supply of small samples. Extracting a sample leads to the destruction of the product, and the separate production of a sample requires additional expenditures and does not always ensure comparable properties. The computer-controlled Fischerscope® H100 Compakt (H100 C) opens entirely new areas of applications for efficient tests of materials and thin coatings both on small samples/micro components and on large specimens such as coated shafts, forming components, etc. Using selected examples, this paper reports about the capabilities of this new measurement technology for applications with small test loads and indentation depths as well as the use of the mobile measuring head H100SMC on large-area and compact specimens.
11th Conference on Hardness Measurement, Celle, Germany, 2002
J.L. Nascimento, F.S. Pires, A.C. Rocha, I.M.V. Caminha
THE INFLUENCE OF MICROSTRUCTURE HOMOGENEITY ON THE UNIFORMITY OF HARDNESS STANDARD BLOCKS
The aim of this work is to correlate the homogeneity of the microstructure of two certified hardness standard blocks, both with the same hardness value range, with its uniformity hardness values. In order to identify the morphological characteristics of the blocks studied, as grain size distribution, an automatic image analysis system with software based on ASTM E112 and ASTM E1382 standards was employed. The hardness measurements were carried out in industrial hardness tester machine, in three different regions of the blocks. The results obtained for both blocks showed that, for the regions where coarsed grains were observed as islands of microstructure non-homogeneity, the hardness values dropped compared with those mentioned in the calibration certificates. The microstructure homogeneity plays therefore an important role on the uniformity of hardness values for reference blocks.
11th Conference on Hardness Measurement, Celle, Germany, 2002
L. Ma, S. Low, J. Song
COMPARISON OF ROCKWELL B HARDNESS (HRB) TESTS USING STEEL AND TUNGSTEN CARBIDE BALL INDENTERS
Significant measurement differences occur in Rockwell B hardness (HRB) tests when using 1.588 mm diameter ball indenters made of steel and tungsten carbide (WC). In this paper, finite element analysis (FEA) is used to simulate the HRB indentation process using steel, tungsten carbide and rigid ball indenters on the same tested materials under the same testing conditions. The influence of the deformable indenters (made of steel and WC) on the HRB indentation is assessed by comparing their FEA results with those of a non-deformable rigid indenter. The deformations of both the indenters and tested materials during the loading and unloading period are analyzed. The effect of deformable ball indenters on HRB hardness measurement values is discussed and further verified by experiments.
11th Conference on Hardness Measurement, Celle, Germany, 2002
R. Barbato, R. Boi, R. Ragazzini
DETERMINATION OF MICRO-INDENTATION HARDNESS OF ORGANIC COATINGS
Many industrial products have to be coated by organic materials not only for aesthetical reasons, but specially to prevent the integrity of the metallic substrate from corrosion attacks during their service life; then, the corrosion resistance of metallic component is often assigned to the physical properties of the coating material. A lot of specific tests are available in the field of surface treatment characterization, in order to assess mechanical, physical and durability properties of paints and varnishes. Among them, indentation hardness allows to investigate on the local properties of a painted layer, not only on the external surface but also into the coating thickness, making it possible to verify hardness at every depth of the layer; non-uniformity in hardness values can be referred to the painting process (curing conditions, coating material, etc.). Hardness measurement technique on the transversal section required particular attention in the specimen preparation; hardness tests were performed by using a Knoop indenter, according to the standard ISO 6441-1. In the present paper are reported the results of several hardness tests performed on the surface and on the transversal section of various aluminium painted samples, some of them partially polymerized to different degrees. The same results have been compared with the results of commonly used tests for coating characterization, as: Taber abrasion test, hardness pencils test, Buchholz indentation test and also impact test.
11th Conference on Hardness Measurement, Celle, Germany, 2002
K. Herrmann, A. Germak, F. Menelao, G. Barbato, G. Brondino
INDENTATION VELOCITY EFFECT ON MARTENS HARDNESS MEASUREMENT
The Martens Hardness (HM) is an important parameter characterising the elasticplastic properties of the to be investigated sample material which is derived from the instrumented indentation test. At present the standardisation of the instrumented indentation test in the framework of ISO/DIS 14577-1, -2, -3 is underway. This standard addresses the macro-, micro- and nanorange of the indentation test. The peculiarities of the nanoindentation test when measuring samples with thin coatings (coating thickness d < 2 µm) will be considered in ISO/CD 14577-4 for which inputs came from CEN TC 184/WG 5 and from the EU-project „INDICOAT“. Martens Hardness presents a number of advantages, but, as any newly defined method, requires a general analysis of influence quantities to determine the sensitivity coefficients necessary for the uncertainty evaluation. Indentation velocity was found to be one of the main influence quantities for Rockwell and Vickers scales, therefore its effect was evaluated in a previous work that indicated an effect much higher than expected. In that work some warning was given, because the analysis was based on the results obtained on a single Hardness Standard Machine, moreover based on a simple experimental plan that did not guarantee any separation of the effects of time and velocities. In the present work these drawbacks are overcome. The analysis is based on an experimental plan that takes into account the load increasing time, the velocity of the initial part of indentation and the velocity of the last part of indentation, that is for the Rockwell and the Vickers method the most important influence factor. Moreover, following the resolution adopted within the recent ISO TC 164/SC3 meeting during which Martens Hardness was extended to cover from nano to macro ranges, experiments are performed on each of these ranges and with different machines, delivering in that way more significant results.
11th Conference on Hardness Measurement, Celle, Germany, 2002
Th. Polzin, D. Schwenk
EXPERIENCES WITH THE DETERMINATION OF UNCERTAINTY BRINELL HARDNESS, PC PROGRAM
After the next revision of the Standards for hardness testing, a determination of uncertainty has to be. part of the Standards. In the following text two methods for the determination, proposed for the ISO Standards of hardness, are described and the implementation of both methods in an Excel-based file is explained.
11th Conference on Hardness Measurement, Celle, Germany, 2002
Th. Polzin, D. Schwenk
WORLD-WIDE UNIFIED SCALES FOR THE ROCKWELL HARDNESS TEST WITH CONICAL INDENTERS
The aim of this round robin test was to discover what needs to be done to achieve the worldwide unification of Rockwell hardness scales using diamond indenters (HRC, HRA, HRD, HR15N, HR30N and HR45N). These scales are the most commonly used and their unification is of high industrial importance. The current degree of unification at an international level was assessed by conducting a round robin test. Seventy four specially developed hardness test blocks were all calibrated by twelve laboratories in eleven countries and the results were compared. Test parameters were specified that were more precise than those required by the standards. The indenters used to make hardness measurements have a significant effect on the measured result. To separate these indenter effects, measurements were made using common indenters as well as the indenters normally used by the laboratories.
11th Conference on Hardness Measurement, Celle, Germany, 2002
M. Tietze, M. Kompatscher
PREDICATIVE HARDNESS TESTING FOR PRODUCTION CONTROL AND MATERIALS DESIGN
In-situ high-temperature rebound hardness testing according to the EQUOTIP® principle is useful to study effects of secondary hardening on strength and thermal stability, e.g., of highly alloyed tool steels. In-line material characterization and in-production testing are now feasible and offer new possibilities for production control and materials design.
11th Conference on Hardness Measurement, Celle, Germany, 2002
M. Fujitsuka, T. Ishibashi, S. Sukigara, H. Amano, M. Ohki
STUDY ON EVALUATION METHOD OF DETERMINING YOUNG'S MODULUS USING ULTRAMICRO HARDNESS TESTER WITH A SMALL BALL INDENTER
The aim of this study is to determine Young’s modulus by means of measured indentation load, depth and elastic recovery displacement of an indenter during loading and unloading processes using a developed horizontal ultramicro hardness tester. In order to determine correctly Young’s modulus of materials in narrower and shallower area of nanometer or micrometer level, authors use very small ball indenters that are made by bearing ball of a diameter in 0.3 mm and 0.5 mm. Several metal specimens [carbon steel, stainless steel, high tension brass and aluminum alloy] are used in test. Young’s moduli of metal specimens calculated on the ball indentation theory show good agreements with that of uniaxial compression test. As a result, effectiveness of evaluation method of determining Young’s modulus with a small ball indenter is confirmed.
11th Conference on Hardness Measurement, Celle, Germany, 2002
E. Reimann
MARTENS HARDNESS - MORE THAN JUST HARDNESS TESTING
Exemplary results of the instrumented indentation test within the macro region are presented to provide an insight into the potential of the Martens hardness test method and to deliver new knowledge. Measurements on reference test blocks are carried out using a Zwick hardness testing machine, which is equipped with digital measurement and control technology. Representative results show, for instance, the influences of test force, as is well-known from Vickers hardness, and of test parameters on the result gained. An overview describes the manifold uses of the hardness measurement head of Zwick, in R & D and in industrial applications.
11th Conference on Hardness Measurement, Celle, Germany, 2002
P. Grau, H.S. Leipner, D. Lorenz, A. Zeckzer
TRENDS IN THE DEVELOPMENT AND APPLICATION OF THE NANOINDENTATION METHOD
One of the most important trends now is the application of nanoindentation for fundamental investigations of elementary mechanisms of mechanical deformation under very high pressure in the local contacted region. Representative examples are given. We have studied in detail the homogeneous generation of dislocations at room-temperature by nanoindentation in locally dislocations-free monocrystals. The discontinuity of load-penetration depth-curve referred to as Pop-in-effect is the result of the nucleation of the first dislocation loops and subsequent drastic plasticity response of the material by indentation due to multiplication processes. The mechanical stresses responsible for this process were calculated in the framework of elastic contact theory (Hertz, Sneddon). The measured critical stresses for loop nucleation are in good agreement with theory of dislocations within the isotropic approach. Corresponding dislocation loops were proved by means of microscopy imaging techniques (transmission electron microscopy (TEM), cathodoluminescence imaging (CL), and imaging of dislocation-etched surfaces.
11th Conference on Hardness Measurement, Celle, Germany, 2002
E. Aslanyan, A. Doinikov
ON EXPRESSION OF HARDNESS MEASUREMENTS RESULTS UNCERTAINTY
Approach to hardness measurements data processing has been examined. The basis of this approach is that the scales of hardness are, in accordance with the general measurements theory, scales of order. The advantage of the method consists in the fact that it is more adequate and simple which is characteristic of hardness measurements as such.
11th Conference on Hardness Measurement, Celle, Germany, 2002
H. C. Schoenekess, W. Ricken, J.-G. Liu, W. -J. Becker
EDDY-CURRENT SENSORS AND THEIR APPLICATIONS TO FORCE AND STRESS MEASUREMENT IN STEEL REINFORCED CONCRETE
The monitoring of bridge constructions can be performed by optimised eddy-current sensors to recognise damages earlier and to reduce rehabilitation expenses. The aim is to measure the coil impedance of an eddy-current sensor positioned close to a pre-stressing cable and to conclude the change of stress in steel of reinforced concrete elements. For this purpose, measurements were taken with specified specimen to investigate the influence from the air gap variation and hysteresis curve.
1st Conference on Civil Engineering Metrology, Celle, Germany, 2002
M. Laube, T. Rusack
CONCRETE STRESS MEASUREMENT - DEVICE AND APPLICATIONS
This contribution deals with the development of a new sensor for measuring stress in massive concrete structures. It starts with a technical overview regarding the apparatus and its theory of operation. At least some application examples from building sites ard results will be shown.
1st Conference on Civil Engineering Metrology, Celle, Germany, 2002
J. Kim, Y. Park, I. Choi, D. Kang
DEVELOPMENT OF SMART ELASTOMERIC BEARING EQUIPPED WITH PVDF POLYMER FILM FOR MONITORING VERTICAL LOAD THROUGH THE SUPPORT
This paper presents a smart elastomeric bearing using PVDF polymer film, which is very sensitive to dynamic loading condition. The PVDF polymer film is inserted into the elastomeric bearing to monitor the normal load, which is applied to the bridge structure. Therefore, the prototype of the smart elastomeric bearing is finally fabricated with the electric circuit for signal of the PVDF polymer film subjected to vertical loading. The evaluation system for smart elastomeric bearing is manufactured with shake, accelerometer and plate. The bearing was tested under sinusoidal loading condition. Finally the system confirmed that real time measurement of elastomeric bearing reaction provides the structure with certain intelligence.
1st Conference on Civil Engineering Metrology, Celle, Germany, 2002
P. Anderegg, R. Brönnimann, Chr. Raab, M. Partl
LONG-TERM HEALTH MONITORING OF PAVEMENT DEFORMATIONS ON AN EXPRESSWAY
The increasing traffic density and increasing axle loads on highways requires an efficient road maintenance. Within a long-term project over 10 years load and pavement deformations on a heavily travelled expressway are measured. A newly developed sensor based on the magnetostrictive principle measures the vertical deformations within the pavement layers in parallel to existing inductive sensors. Short-term data of the two different systems and longterm data of the new sensor over a one year period are presented and further improvements discussed.
1st Conference on Civil Engineering Metrology, Celle, Germany, 2002
W. Habel, D. Hofmann, F. Basedau, A. Barner, S. Crail, D. Reichel, U. Schreiner, E. Lindner
STATIC AND DYNAMIC MEASUREMENTS ON A NEWLY DEVELOPMENT PRECAST CONCRETE TRACK FOR HIGH SPEED RAILWAY TRAFFIC USING EMBEDDED FIBER-OPTIC SENSORS
In a German slab track system (“Feste Fahrbahn” FF, system Bögl) for speeds up to 300 km/h and more different fibre optic sensors have been embedded in several levels and locations of the track system. The track system consists of prestressed precast panels of steel fibre concrete which are supported by a cast-in-situ concrete or asphalt base course. The sensors are to measure the bond behaviour or the stress transfer in the track system. For that, tiny fibre-optic sensors - fibre Fabry-Pérot and Bragg grating sensors - have been embedded very near to the interface of the layers. Measurements were taken on a full scale test sample (slab track panel of 6.45 m length) as well as on a real high speed track. The paper describes the measurement task and discusses aspects with regard to sensor design and prefabrication of the sensor frames as well as the embedding procedure into the concrete track. Results from static and dynamic full scale tests carried out in the testing laboratory of BAM and from measurements on a track are given.
1st Conference on Civil Engineering Metrology, Celle, Germany, 2002
J. Knapp, R. Helmerich, W. Habel
MONITORING BRIDGES OF THE NEW LEHRTER BAHNHOF IN BERLIN BY MEANS OF LONG-TERM STABLE SENSORS
Two concrete bridges of the new Lehrter Bahnhof in Berlin have to be monitored with regard to their deformation performance during construction and later over several years. For this purpose sensors with excellent long-term stability are needed. The paper describes a new system for the measurement of settlements and elevations by means of laser-based optics and hydrostatic levelling, the application of fibre-optic strain sensors and conventional strain gauges, inclinometers and temperature sensors as well as model tests on pre-stressed concrete beams inside and outside the laboratory.
1st Conference on Civil Engineering Metrology, Celle, Germany, 2002
Tang Hongwei, Li Wansheng, Li Yuhong
APPLICATION ON MEASUREMENT OF PRE-STRESS LOSS IN CONCRETE STRUCTURE WITH FIBER-OPTIC SENSORS
As one of the important works in the pre-stressed concrete structure design, magnitude of the pre-stress loss has not been measured conveniently until now. A suitable measuring technique for pre-stress loss is the studying goal of researcher in a long time. In the present work, the fiber-optic measuring technique has been introduced to measure the pre-stress loss, and all of the measuring works were conducted on the model of a wastewater tank. Result of the measurement shows that optical fiber sensor can be used to measure the pre-stress loss in engineering, and the short-term pre-stress loss of steel strand is strongly effected by the arranging manner of steel strand, the magnitude of pre-stress loss measured in the present work is less than 20%.
1st Conference on Civil Engineering Metrology, Celle, Germany, 2002
Zelimir Simunic, Ivan Gasparac, Bozidar Pavlovic, Mario Vrazic
BRIDGE TESTING AND MONITORING WITH A MEASUREMENT SYSTEM BASED ON THE INDUSTRIAL COMMUNICATION NETWORK
Bridge testing and especially monitoring are very important for evaluating the structure state. Using modern technologies (ICT) it is possible to achieve on-line permanent monitoring and therefore we are trying to design such measurement system based on industrial communication network with PROFIBUS protocol.
1st Conference on Civil Engineering Metrology, Celle, Germany, 2002
Ludwik Finkelstein, Kenneth T. V. Grattan, Sanowar H. Khan
PHYSICAL SCIENCE IN MEASUREMENT AND INSTRUMENTATION EDUCATION
The paper presents arguments for the place of physical science in the teaching of measurement and instrumentation as a systematic discipline. It is argued that the discipline should be taught as general transferable concepts and principles, based on the science of information and systems. It is shown, however, on the basis of a model of the architecture of a measurement system that the concepts of information and systems alone are inadequate to treat sensors, the observed system, the interaction between them, and also the problems of inferential measurement. It is argued that these components and processes require to be described, analysed and designed using also the concepts and principles of physical science. The essential role of physical experimentation in the laboratory in the teaching of measurement and instrumentation is discussed. The place of physical science in measurement and instrumentation curricula is discussed, and it is argued that physical science should form a particularly important role in the education of specialist designers and developers of measurement and instrumentation systems.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Jerzy Fraczek
ACCREDITATION AND QUALITY ASSESMENT OF THE UNIVERSITIES OF TECHNOLOGY
After couple years of discussions, on different levels, at different academic centres and academic institutions, the very important decision was undertaken concerning the Teaching Quality Assessment. As a result of the act of July 20th 2001, regarding changes to the act of higher education and the act of polytechnic school, the National Accreditation Commission was created – the statutory organ of higher education working for the quality of education. According to the expectations and demands of the academic community the whole higher educational system is evaluated by equal set of standards.
The National Accreditation Commission completely takes over the duties regarding the evaluation of applications for opening new schools, studies and giving rights to train for a masters degree. The Commission has the rights to estimate the quality of training and the conditions of higher studies in all polish universities: public, not public, academic and vocational. The last task will lead to many inspections and controls.
According to “The Status of the National Commission of Accreditation”: "The Commission cooperates with national and international organisations that assess the quality of education and accreditation". In the field of cooperation the following questions have to be discussed:
How to compare accreditation results of the National Accreditation Commission in Poland with the rules concerning:
1) Accreditation of Colleges and Universities in the Middle States Region of the United States of America
* Silesian University of Technology, Institute of Automatic Control, Akademicka 16 str., 44-100 Gliwice, Poland, e-mail: jkf@oak.ia.polsl.gliwice.pl 2) The Teaching Quality Assessment conducted by the Higher Education Funding Council for England
3) FEANI Register of European Engineers
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Jerzy Fraczek, Roman Wyzgolik, Stanislaw Walus, Dariusz Buchczik
HOW TO TEACH ABOUT MEASUREMENT SYSTEMS - EXPERIENCES FROM THE INTERDISCIPLINARY EDUCATION
Since 1999 the Faculty of Automatic Control, Electronics and Computer Science offers studies in English in: Automatic Control and Robotics, Electronics and Telecommunication, Computer Science, with various specializations. Lectures and laboratory classes are in English. The idea of this paper is to present our contribution in this new programme as the Measurement Systems Group, which is a part of the Institute of Automatic Control. We started with our lectures, untitled "Measurement Systems", in the last year (2001), for students which have completed three half-year semesters. After the half-year lecture course, students have begun laboratory classes.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Bogdan A. Galwas, Remigiusz J. Rak
VIRTUAL LABORATORY - A FUTURE PART OF THE NEW WEB-BASED MODEL OF UNDERGRADUATE ENGINEERING STUDIES DEVELOPED BY WARSAW UNIVERSITY OF TECHNOLOGY
The article gives a review of reasons for developing and adopting a new web-based model of studies by Warsaw University of Technology. That is followed by a description of the Internet and multimedia - based educational model, known as SPrINT. The article presents also a structure of the four-year engineering studies offered by Electrical Engineering Faculty, Faculty of Electronics and Information Technology and Faculty of Mechatronics for given specialization. Then follows a description of the structure and tools of the electronic books. One of the subjects common for all students of the three Faculties is Virtual Laboratory. Virtual Instruments, as well as networked and distributed measurement systems, are the natural tools, which can be used in a modern didactic process for creating virtual laboratories.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Anna Golijanek-Jedrzejczyk, Dariusz Jedrzejczyk, Ludwik Referowski, Dariusz Swisulski
EDUCATIONAL LABORATORY STAND FOR REMOTE MEASUREMENT SENSORS’ DYNAMIC CHARACTERISTICS
This article presents a laboratory stand that enables one to test properties of temperature sensors over Internet. The measuring system lets determine dynamic characteristics of the sensor. It was designed for didactic applications, which can be used by extra-mural or ill students although some solutions may be used by industry.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Kenneth T. V. Grattan, Sanowar H. Khan, Ludwik Finkelstein
PHOTONICS AND OPTICAL MEASUREMENT: EDUCATION FOR TODAY’S ENGINEERS
The paper presents an illustration of the use of photonics and optical measurements in today’s engineering world and emphasizes the need for and value of the field which is seen as a key subject for current engineering education. The paper emphasizes the place of photonics when viewed within a systems approach to measurement and instrumentation, but also stresses the value of the appreciation of the fundamentals of physical science to achieve a full understanding of modern devices of this type. The relationship of photonic measurement systems to optical communications systems is stressed, as is the commonality of the approach to the two. The role of modelling as a key tool in the system design is emphasized, and an illustration given of a modern fibre optical measurement system to exemplify the points raised.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Jan Holub, Radislav Šmíd
LABORATORY EXERCISE ON COMPLEX MEASUREMENT TASK: VOICE TRANSMISSION QUALITY MEASUREMENT
The laboratory exercise dealing with voice transmission quality of service measurement in mobile networks that is being designed in Czech Technical University in Prague is described in the paper. The final experiment that is made during the exercise is based on measurement of voice quality of the GSM connection established between student’s GSM terminal and remote GSM station of measuring system. The measurement is performed by means of measurement system that has been developed at the University. The remote station can work either in fully automatic mode or can be controlled via web interface. Deeper understanding of exercised topic is expected in comparison with plain simulations. On the other hand, all the exercise takes less time in comparison with excursion to telecommunication switch where similar measurement systems can be found and tested.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Krzysztof Jellonek, Malgorzata Kotulska
NEW CONCEPTS AND TECHNIQUES IN EDUCATION OF BIOMEDICAL ENGINEERS IN COMPUTER SCIENCE
Modern university education is very strongly based on computer techniques, which provide necessary computational power to develop specialized software. Very intuitive graphical programs became indispensable tools for word and graphics processing, data storage, and advanced computational tasks. An increasing role of information availability from the data stored on web pages and network accessible data bases can be observed. This immense potential source of information requires appropriate searching tools and algorithms. In this situation a well-scheduled track through computer science courses, for students of various specializations, is an essential issue. This problem is especially acute in education in Biomedical Engineering since application of computer methods to medicine, computational biology, and bioinformatics requires an approach that differs from classical methods. We discuss concepts and techniques in teaching computer science courses, comparing three specializations from the Faculty of Basic Problems of Technology in Wroclaw University of Technology: Biomedical Engineering, Computational Physics in Science and Technology, and Mathematical Aspects of Computer Science.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Barbara Juroszek, Ewa Dziuban
MEASUREMENT OF PROPERTIES OF BIOMEDICAL SUBJECT - COGNITIVE TARGETS FOR STUDENTS AT TECHNICAL UNIVERSITIES IN WROCŁAW AND RZESZÓW
Authors compared courses related to biomedical measurements at Wrocław University of Technology, where they are a base of speciality education and at Rzeszów University of Technology, where they are merely a supplement on measurements of living organism for students of Metrology. This comparison revealed that there is a "canon" of the necessary and common knowledge offered to students.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Wlodzimierz Konecki, Jakub Konecki
TEXPRO – THE EDUCATIONAL COMPUTER PROGRAM FOR THE MODELING OF TEXTILES PROPERTIES
The new worked-out computer program, named TEXPRO, for modeling of textiles properties is presented. The program is written in C++ language and built in form of handbook divided into particular exercises. It is designed for students doing the laboratories from subject "Structure of Yarns and Textile Fabrics".
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Jerzy M. Korczynski, Andrzej Hetman
CALCULATION OF EXPANDED UNCERTAINTY
The main purpose of the paper is to present a method of calculation of the expanded uncertainty at required confidence level. It is elaborated as a piece of software with the main intention for metrology and quality engineering courses. The definition based algorithm is used and convolutions of different probability density distribution are precisely calculated. The uniform, triangular, normal and t-Student distributions are implemented in the software. One of the advantage is no limitation of encountered measurands.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Maarten Korsten, Paul Regtien
COMPUTER SUPPORTED LABORATORY REPORTS OF EXPERIMENTAL WORK
Reports on experimental work should be based on a well-documented laboratory report. With the laboratory report we mean the logbook, kept during the experiments. Making such a laboratory report is an important part of the practical courses at our Electrical Engineering faculty in Twente. Nowadays our students write their report on paper. We consider the option to write it directly on the computer so that it can be integrated with managing the measurement results. Doing this however will pose severe requirements to the user friendliness of the software environment. In this paper the idea of an integrated computer environment for doing experimental work is discussed, together with some problems.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Robert Lukaszewski, Wieslaw Winiecki
NEW INFORMATION TECHNOLOGIES IN MEASURING SYSTEMS DESIGNING
The paper presents an influence of new information technologies upon measuring systems designing and proposes a new course that covers new trends in measuring systems designing. Distributed structure of modern measuring systems requires the use of special software technologies for design software of such systems. Possibilities of applying some modern information technologies for these purposes are considered. In the second part of the paper a program of a new course, concerned measuring system software designing, is presented. An example of student project, designed in the frame of the course, is presented.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Jarosław Makal
EDUCATION OF METROLOGY IN ELECTRONIC AND TELECOMMUNICATION STUDIES AT TECHNICAL UNIVERSITY OF BIAŁYSTOK
In this paper the general description of the schedule of studies on Electronic and Telecommunication at Technical University of Bialystok from the point of view of delivering metrology knowledge is presented. Also three typical subjects of metrology like the base of metrology, surveying of electronic and technique of experiment are underlined. The attempt of qualification the profile of graduate is one of the final conclusion of this work.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Zbigniew Moron
SENSORS – WHAT AND HOW SHOULD WE TEACH?
There is no question 'if' or 'why' we should teach sensors. The contemporary world cannot operate without them. A basic understanding, principles of choice and principles of application of sensors in instrumentation systems are of fundamental importance in all disciplines of engineering. Fascinated by information processing people often forget that the function and also properties of every instrumentation system are defined by both the sensor and the software support provided. This paper presents some basic information on sensors and sensing, and the main problems faced when teaching them. It is intended to be a platform for discussion.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Ludwik Referowski, Ryszard Roskosz, Dariusz Swisulski
NEW POSSIBILITIES IN THE EDUCATIONAL PROCESS OF ELECTRICAL MEASUREMENTS
In the paper are presented the possibilities of preparations modern, educational tools which in the form of virtual instruments are very helpful for educational process in electrical measurements. These dynamic instruments enable to perform during the lectures demonstrations which explain better lectured theory of electrical measurements, especially when some kinds of phenomena are presented in slow down time scale. Another group of virtual instruments enable to simulate measuring sessions which are realized later in the university laboratory. The third group of virtual instruments explain the idea of remote measurements with help of modern technologies. These measurements are realized on different industrial objects. The paper presents several solutions of educational virtual instruments designed by the team of Technical University of Gdansk. They were realized using the software LabVIEW of National Instruments.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Shigeru Takayama, Komyo Kariya
LEARNING METHOD OF MEASUREMENT ENGINEERING THROUGH USER NAVIGATION INTERFACE OF VIRTUAL INSTRUMENT
This paper describes the extensional function of user navigation interface of virtual measuring instruments which supports user’s self-learning in experiment. The extensional function is presented by representation of knowledge database through internet browser. It is very effective for user to learn and investigation the knowledge of measurement engineering with training of operation of real or virtual measuring instruments in experience. The knowledge exploration by hyperlink through HTTP presents new heuristic learning method for user comparing with systematical learning method by lecture.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Stanislaw Walus, Janusz Zelezik
THE MASTER'S THESES ON THE ESTIMATION OF METROLOGICAL PROPERTIES OF MEASURING INSTRUMENTS ON THE BASE OF THE EXPERIMENTAL INVESTIGATIONS AND THE MATHEMATICAL MODELLING
The students of the Department of Automatic Control, Electronics and Computer Science are preparing their master's theses in Measurement Systems Group of Institute of Automatic Control. They include the experimental investigations in Institute laboratory of various measuring instruments and also the mathematical modelling of primary devices of flowmeters and other instruments. Some results of master's theses were published in Polish scientific newspapers and in international conference proceedings. The measurement system for identification dynamic model of thermometers by "in-situ" method was elaborated. The measurement system enables identification of dynamic models of resistance thermometers by three methods: classical step-input method and two in-situ (internal input) methods. The mathematical modelling of distorted velocity distributions enables the investigation of errors of sampling flowmeters. On the base of the experimental data from rivers the modelling investigations for sampling flowmeter used for open channel were made.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Roman Wyzgolik, Dariusz Buchczik
INTEGRATED SOLID STATE SENSORS IN ENGINEERS EDUCATION – EXPERIENCES AND PLANS FOR FUTURE
The measurements of non-electric quantities with electric methods have a long-standing tradition at the Silesian University of Technology. In this paper we would like to present the main idea and topics of the lectures and briefly describe the laboratory exercises. We also discuss the plans for the future.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Madiar Zaripov, Irina Petrova, Victoria Zaripova
PROJECT OF CREATION OF KNOWLEDGE BASE ON PHYSICAL AND TECHNOLOGICAL EFFECTS
In the new millennium the change of technological and technique generations occurs in a temp unprecedented earlier. Therefore in order to train high-qualified engineers able to quickly, efficiently react to society’s new needs it is necessary for them to upgrade their knowledge permanently.
Indicators consumption increase both in quantity and in nomenclature needs an acceleration of production rate owing to automation of design process. The problem is that a description of various physical processes on which the principle of indicators action is based, is being carried out with the use of physic-mathematical apparatus, appropriate to this class of phenomena. It hampers the design process automation, increases new indicators development time and their cost. The article considers a united system approach in the field of sensitive elements theory, invariant to the physical nature of phenomena and processes used and in the field of methods and instrumental means of these elements structural designing with following process automation.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002
Janusz Zelezik, Stanislaw Walus
THE CONSTRUCTION OF THE MEASURING INSTRUMENTS AS THE SUBJECT OF MASTER'S THESES FROM METROLOGY OF NON-ELECTRICAL QUANTITIES
The students of automation and robotics, electronic and telecommunication are preparing their master's theses in Measurement Systems Group of Institute of Automatic Control. They also include the projecting and constructing of measuring instruments and measuring systems. These are dedicated to the laboratories in the Institute, as well for industry. The pocket radiometer was projected and constructed. It consists of the primary device with Geiger-Müller counter, the secondary device and of the power supply. The radiometer has series connections RS232C. The calibration stand for rotameters based on the soap film flowmeter principle was projected and constructed and put on the market. The digital measuring interface was projected and constructed for investigating of the piezoresistors (for strange gages, pressure gages, ...). The universal interface for transducers UTI and the microcomputer AT89C52 are used. The sensors can be used in the bridge or half-bridge, and for the resistance of 120 - 10000 ohms. The results of measurements are displayed on LCD display. The instrument is connected with help of the RS 232C interface with computer.
Symposium on Education in Measurement and Instrumentation, Wroclaw, Poland, 2002

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