Vol. 62 | nr. 4 | Octombrie - Decembrie 2014 Articolul 9

Calibration method of capacitive grating torque sensor based on phase difference
(full text in English)

Changxin CHEN, Tiehua MA, Hong JIN
In order to improve the accuracy of the capacitive grating torque sensor, this paper proposes a calibration method of the capacitive grating torque sensor based on phase difference. The main idea of this calibration method is phase difference, which uses the universal dividing head to generate a high precision torsion angle and make the still sleeve rotate. This calibration method does not load torque, but produces a high precision relative rotation torsion angle as the standard input, which can achieve the same torsional effect to realize the torque sensor calibration. Firstly, the structure and basic principle of the capacitive grating torque sensor is described. Secondly, the relationship among torque, torsional angle and phase difference are introduced. Thirdly, the calibration system is introduced. Finally, the calibration experiment is carried out and the experiment results are analyzed by MATLAB software to obtain the calibration error. The experiment result shows that the calibration method of phase difference is correct.
Keywords: capacitive grating, torque sensor, phase difference, calibration method, rotational shaft