A three-dimension high-precision and non-contact dynamic angular displacement measurement system based on heterodyne interference

Scientific instruments and facilities used for calibrating the dynamic angle error of inertial instruments have played more and more important roles in mechanism error research and accuracy improvement. Present attitude measurement methods can not simultaneously meet the requirements of the inertial instrument angle error calibration in dynamic environments such as linear or angular vibration. Based on the collaborative integration and modeling calculation of single-point laser Doppler vibrometer, this paper proposes a dynamic attitude measurement system that can completely realize non-contact real-time accurate three-dimensional rotation angle measurement, filling in the blank of non-contact dynamic angle error calibration of inertial instrument. Besides, we propose a distance calibration method to reduce the angle measurement error from 0.34° to 0.0072°, which fully satisfies the non-contact measurement requirements of the inertial instrument.