An Efficient Calibration Method for Triaxial Gyroscope

This paper presents an efficient servomotor-aided calibration method for the triaxial gyroscope. The entire calibration process only takes about one minute, and high-precision equipment is not used. The main idea of this method is that the measurement of the gyroscope should equal to the rotation speed of the servomotor. A six-observation experimental design is proposed to minimize the maximum variance of the estimated scale factors and biases. Besides, a fast converged recursive linear least square estimation method is presented to reduce computational complexity. The simulation results specify the robustness under normal and extreme condition. We experimentally demonstrate the achievability of the proposed method on a robot arm and implements the method on a microcontroller. The calibration results of the proposed method are verified by comparing with a traditional turntable method, and the experiment indicates that the error between these two methods is less than $10^{-3}$. By comparing the calibrated low-cost gyroscope reading with the reading from a high-precision gyroscope, we can infer that our method significantly increases the accuracy of the low-cost gyroscopes.