This contribution describes new methods to characterize and determine both, the drift and the non-linearity of piezoelectric force measuring devices. The influence of the drift and dif-ferent procedures for the drift calculation are presented. In addition the influence of different load regimes and evaluation procedures is discussed. The measurements carried out reveal that not the drift, but in particular the non-linearity is the criterion crucial for a classification of piezoelectric force transducers according to standards commonly applied to strain gauge force transducers. The results of this contribution are necessary and important for the development of standards required for the calibration of piezoelectric force measuring devices in force stan-dard machines.

The living creatures provide a lot of gripping biomechanisms. The study of these biomechanisms makes possible the discovery of interesting equivalent mechanisms, which can be used for industrial robots in many fields of activity. It is possible to obtain some technical gripping mechanisms starting from the ones of the living creatures in their biological evolution: insects (stag beetle), birds (parrot), marine (crawfish) or terrestrial (elephant) animals, human beings. It is a good idea to try the synthesizing of a universal gripping mechanism.

A new dead weight force standard machine covering the range from 10 kN to 1 MN has been designed and constructed at the National Institute for Standards (NIS)-Egypt, by GTM GmbH.
This machine incorporates an electromechanical system that allows the generation of any load from 10 kN to 500 kN in steps of 5 kN with only 10 masses by selecting a suitable combination of these, while keeping the load on the transducer under calibration constant. Furthermore, it allows the generation of additional loads of up to 500 kN, so that 1 MN is reached by full deadweight action and full substitute load at the same time without significant loss of accuracy.
The forces generated by the various masses can be checked against a reference mass without any dismantling operation. The machine also serves as a precision pressure balance of a 5 MN hydraulic force standard machine. The amplification system formed is of 10:1 ratio.
The paper presents the special design features of the machine and the design considerations with a brief account of the verification of the machine. A second paper will follow to present the evaluation of the metrological characteristics of the developed machine.

This contribution describes different measurement facilities and procedures for the calibration of piezoelectric force measuring devices. In National Metrology Institutes forces are generated in force standard machines in force steps. In force calibration machines of industrial calibration laboratories forces can be applied in steps or continuously. The traceability is realised with force transfer standards, which are calibrated in force standard machines. A comparison of these different calibration procedures is discussed in this contribution.

In this paper, present status of the developing impulse generator based on the law of conservation of momentum is reviewed. Impulse responses of two commercial force transducers are evaluated by means of this method. In the experiment, an object levitated with sufficiently small friction using a pneumatic linear bearing is collided with a force transducer. The inertial force acting on the object is measured as the product of the mass and the acceleration. Approximately 160 sets of collision experiments, whose impulses with the maximum value of approximately 20 to 230 N with the half value width of approximately 10 ms to 40 ms, have been conducted using two commercial force transducers and two dampers. The instantaneous value of inertial force is measured with the sampling period of approximately 0.15 ms. its standard uncertainty is approximately 0.9 N, which corresponds to approximately 0.4 % of the maximum applied impulse.