This paper presents the needs in Mexico for larger ranges in torque calibration. The design of a torque standard to meet, and surpass, those needs are here included. The general design considerations, the layout of the system and the subsystems designed for the torque national standard for 20 k·Nm in Mexico are discussed and included in this paper.

This paper describes measurement of resultant acceleration of motion and gravity in 3D space based on sensing a metallic ball position on elastic layer housed in a spherical shell. Construction of different types of silicon rubber is introduced and their displacements against pressure are calculated by using the Hertz' law. Since the resultant acceleration makes the ball roll toward the direction to find a balanced position in the shell, the center position of the metallic ball is measured. The rubber layer is concentric to the shell and liable to distort so that three proximity sensors of high-frequency oscillation type can detect characteristics of sink versus pressure. We show measurement principle of extracting the acceleration by using the characteristics. Experimental results are shown and compared among various rubbers to have the most appropriate design of the sensor. We got practical data such that angular error less than ±7.4 deg; amount error less than 2.86 x 10^-2 m/s²; force sensitivity 4.9x 10^-2 N; insensible range less than ±3.8 deg; periodic time 95 ms.

The continuous calibration method of force transducer represents a very helpful method since the calibration can be carried out in a short time compared with the step by step method. Another advantage of the continuous calibration method is the possibility of recording the responses of the standard force transducer and the force transducer to be calibrated synchronously. This could be done using two different channels of the displaying device. The disadvantage of this method is the difficulty to define exactly constant certain loads at each loading series during the calibration. The continuous method shows better measurement uncertainty than the step by step method, where as a lot of calibration points are considered in the analysis. One important factor for the results of the continuous calibration method is the response rate. Rates less then 0.08mV/Vs showed good agreement results of the two methods.

This article is concerned with the use of counterrotating mechanical bearings in torque calibration sys- tems. First a short overview on some general aspects of this bearing type will be given, which includes a general description of their construction as well as of their functionality. The main section deals with experimental examinations made on the performance of counterrotating bearings. These experiments were completed mainly using the horizontally arranged MIKES-RAUTE 2 kN·m torque standard calibra- tion device. Additionally initial results gained with the new vertically arranged 20 kN·m torque reference device are included. Main points of interest were the particular elements of the uncertainty budget as stated in EA-10/14. They are opposed for counterrotating and standing bearings. Also some investiga- tions about other error influences of the bearings are presented. Overall these results show that counterro- tated bearings can provide a strong reduction of uncertainty but also need some further investigation es- pecially in vertical devices.

For the determination of the local gravity high precise mobile gravimeters are in use since more than a hundred years. As a result of the basic measurement principle the determination is carried out point-by-point with the consequence that the procedure is time consuming and expensive. Thus in many countries the results of several measurement campaigns have been collected over decades. Whereas the measured values are available to the public only to some extent, the data were of- ten processed to gravity anomaly maps for the purpose of geological ground surveys. In this research two samples of gravity anomaly maps of Northern Germany and Italy are intro- duced with a detailed description of the rebuild of a gravity value from an anomaly map. For the single steps a theoretical budget of the uncertainty is given which has been verified by inde- pendent control points.