Model-Based Research on Deviation in Dynamic Force Sensor Calibration Process

Abstract

For dynamic force calibration, it is essential to accurately determine the force applied to a force sensor. The dynamic force calibration device at Changcheng Institute of Metrology and Measurement uses a laser interferometer to measure the impact force of a falling mass. However, due to the base vibration and inertia forces, the force calculated through the hammer acceleration measured by the laser interferometer and the force measured by the sensor are different. This difference can be observed in calibration experiments by comparing the signals obtained by the laser interferometer and the calibrated force sensor. To correct the deviation and explain this difference, three models are proposed and analyzed in this study. The three models were designed using different degrees of freedom according to different dynamical hypotheses. A lnear fitting approach was used to identify the model parameters. To verify the model and parameters, a simulation model was obtained, and it was calculated using SIMULINK. Subsequently, the simulation model was compared to the experimental data. The results in this study show that the three-degree-of-freedom model can accurately reflect the dynamic behavior of the calibration device. Therefore, the measured reference force can be corrected to obtain the force measured using the force sensor through a quantitative model of this kind, and this correction can improve the dynamic force sensor calibration process.