This paper presents a comparison of milligram scale deadweight forces to electrostatic forces that is generated from an electrostatic sensing & actuating force measurement system recently built in Center for Measurement Standards, Industrial Technology Research Institute (CMS/ITRI). In the first section, we briefly introduce the electrostatic sensing and actuating force measurement system, and then we describe the experimental setup for the comparison and the results. Finally, we give a discussion and outlook.
Keeping in mind the need to have lower measurement uncertainties associated with force standard machines (FSM) to calibrate force instruments, the National Physical Laboratory of India (NPL(I)) has recently installed a new 1 MN force standard machine. The force is generated by dead weights up to 100 kN and a lever multiplication of dead weights up to 1000 kN. The machine has certain novel design features, which result in the lowest uncertainties. This paper contains a description of the functional principles and new design aspects of this machine. The uncertainties of measurements are...
The new version of the international standard ISO 376:2011 gives the possibility to carry out the calibration of force transducers without hysteresis and provides a new approach for calculation of the expanded measurement uncertainty. This paper presents an overview of how the changes affect the results in the calibration certificates of different types of industrial force transducers. A comparison is made between classification and measurement uncertainty based on ISO 376:2004 and EA10/04 and the same values based on the new ISO 376:2011 version.
The Austrian national metrology institute, the Federal Office of Metrology and Surveying (BEV) developed and realised in 2008 an automatic dead weight machine to determine small forces in the range of 1 µN - 10 N with a special construction that allows to measure continuously from 10 N tensions to 10 N compressions. It makes possible to cover the complete range without changing the mounting of the force transducer under calibration. After the successful establishment of this equipment, the BEV started in 2010 together with the Institute of Production Engineering (IFT) of the Vienna...
Traceability of multicomponent measurements is still at an underdeveloped stage. Calibration facilities are rare compared with the diversity and number of applications of multicomponent transducers. Public calibration guidelines are not available. As GTM works step-by-step on the improvement of multicomponent measurements, a new calibration procedure was developed and registered for accreditation at the German Accreditation Body (DAkkS). The procedure yields the complete description of the force vector independent of its direction and magnitude, and the corresponding uncertainty matrix....
Platform-type manual mass comparators are commonly used for the calibration of high precision heavy mass standards. While some automated heavy mass calibration systems are available commercially, they are very expensive and are not economically viable for most laboratories offering calibration services. NMC, A*STAR has developed a low-cost, automatable, weights handling system for use with commercially available platform type mass comparators. This system is designed to be versatile and adaptable for easy loading and unloading of reference and test mass during calibrations. With this system,...
A new mass measurement device using a damped dynamic vibration absorber is proposed and fabricated. The frequency response curves of a mass-spring system with a dynamic vibration absorber pass through a point that is independent of damping in the absorber. The proposed device utilizes this fixed point to estimate mass independently of damping. The principle of measurement was described on the basis of a mathematical model. An experimental apparatus was designed and fabricated. The fundamental properties necessary for precise measurement were certified experimentally.
The paper describes a new method to verify the fixed electronic scales or called mobile scales being weighing range of 50 - 150 t. It consists of 4 parts: standard weights of class M1, a 150 t mass comparator (MC), a set of moveable build-up force standard machines( MBM) and mobile scale (MS) to be verified, which is called 4M verification system(4MS). The paper describes principle, construction and specifications of MBM. It has been done to make comparison of the two verification methods by M1 weights and MBM, of which the verification results are quite agreeable.
In this paper, a method for deriving significant parameters for the description of the dynamic behaviour of electromagnetic force compensated load-cells (EMC) from its impedance-frequency-response is presented. With these parameters, the dynamical behaviour of a loadcell can be depicted and classified near its main resonance frequency, or by going the inverse way the load-cell can be designed based on the favored parameters to fulfill the desired criteria concerning the dynamical behaviour. This method is based on the estimation of parameters describing the behaviour of electrodynamic...
The Austrian Federal Office of Metrology and Surveying (BEV) has developed and realized in cooperation with Sartorius AG (Göttingen) and the Vienna University of Technology a new 1 kg high-precision mass comparator. The new balance is intended to be used for automatic calibration of weights with high precision, for the realization of the mass scale in the range from 10 g up to 1 kg and for mass calibration of density standards.