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.

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.

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.

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.

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.