Oliver Mack
INVESTIGATIONS OF PIEZOELECTRIC FORCE MEASURING DEVICES FOR USE IN LEGAL WEIGHING METROLOGY

In conjunction with low-drift charge amplifiers static force and weighing measurements get more and more important for piezoelectric force transducers if the measuring time and time of load change are in the range of a few minutes. The presented investigations according to the international recommendation OIML R60 [7] point out, that piezoelectric sensors can be used for static applications with low accuracy requirements (e.g. class D for ordinary accuracy weighing instruments). With suitable methods for compensation or adjustment the sensors even meet the higher requirements of medium accuracy class C (e.g. commercial scales). Especially for high nominal loads the piezoelectric measurement technology offer unused potentials also for static precision measurements.

M. S. Kim, I. M. Choi, Y. K. Park, D.I. Kang
ATOMIC FORCE MICROSCOPE PROBE CALIBRATION BY USE OF A COMMERCIAL PRECISION BALANCE

In this paper, we investigate the characteristics of commercial AFM cantilevers and force calibration cantilevers in the range of 10 nN ~ 1000 µN by use of a high precision balance with resolution of 1 nN and 1-D fine positioning stage. This document is a guideline to the authors of papers to be presented at the TC3 2005 conference. These directions are written in the format required for papers. We advise you to download these directions as a MS Word document and use it as the template for your paper because it contains all necessary formats and styles. Papers should be submitted before October 30, 2004. The paper must be written in English, and length is limited to 6 pages, including graphs, figures, reference list.

Thomas Fröhlich, Thomas Fehling, Benno Gatzemeier, Detlef Heydenbluth
SARTORIUS SUSCEPTOMETER FOR PRECISE MEASUREMENT OF SUSCEPTIBILITY AND MAGNETIZATION OF WEIGHTS

The Sartorius Susceptometer is a commercially available susceptometer as described in the Draft revision of International Recommendation OIML R111. It comes with a calibration sheet. The procedure of the factory calibration is described. A measurement comparing five calibrated susceptibility standards is discussed. The magnets used for calibration are monitored concerning the stability of the magnetic dipole moment over about one year.

Michael Kobusch, Thomas Bruns, Lioba Stenner, Sven-Patrick Schotte
IMPULSE FORCE INVESTIGATIONS OF STRAIN GAUGE SENSORS

This paper presents new investigations of strain gauge force sensors subject to impulse loads. Different approaches regarding the determination of the fundamental axial resonance are discussed in order to get information about a practical evaluation method for common-type strain gauge sensors under dynamic loads.

Chi Kah Lim, Bernd Glöckner, Thomas Allgeier
SHORT AND LONG-TERM BEHAVIOUR OF A 55 kN / 2.2 MN LEVER DEADWEIGHT FORCE STANDARD MACHINE

This paper describes the latest results from the re-verification of a 55 kN / 2.2 MN lever deadweight force standard machine at SPRING Singapore. For the first time, a lever machine was successfully compared against deadweight machines (from PTB) at the high level of 2 MN in both tension and compression with an uncertainty in the 1E-4 range. Similarly, the same applies to the 55 kN machine with an uncertainty of ±2E-5. For the 55 kN machine, both short-term and long-term uncertainty has been established. The machine had been the subject of an earlier comparison measurement with the PTB in the compression range. In addition, the periodic maintenance results of this 55 kN / 2.2 MN lever deadweight force standard machine will also be discussed. To monitor the drift and stability of the force realised, a total of 5 SPRING FTS were measured according to fixed protocols over time. The lever amplification ratio was also checked at intervals using a 50 kN FTS. From an earlier maintenance check, it was discovered that there was a significant drift in the lever ratio in March 2003 (12 months after commissioning). However, the deadweight forces continued to be realised within the ±2E-5 uncertainty. The lever ratio has since been adjusted back to producing loads which are magnified exactly 40 times from deadweight forces, demonstrating that it is capable of achieving ±1E-4 short term uncertainty. This was confirmed by the comparison with PTB up to 2 MN in both loading directions. Subsequent measurements demonstrated that the lever ratio has been stable. The same is also true for load reproducibility and repeatability at both the deadweight and lever machine, indicating that the long- term uncertainty is now satisfactory as well.