Outfield Calibration Scheme for Tri-axis MEMS gyroscope

Due to the advantages of small, light and low-cost, Microelectromechanical system (MEMS) gyroscopes are used in the area of navigation. To improve the accuracy of MEMS gyroscopes, an outfield calibration scheme is proposed. The bias, scale errors and installation errors can be estimated simultaneously without high precision angular velocity reference provided by rotation platform. Firstly, the relation between gyroscope output and accelerometer output is built. Secondly, according to the 12-parameter error model of gyroscope, the calibration model is obtained. Finally, UKF estimation algorithm is used to estimate the bias, scale errors and installation errors. The proposed calibration scheme for tri-axis gyroscope is suitable for low precision MEMS gyroscopes which cannot be sensitive to the earth's rotation. simulation and experimental results show that the accuracy of gyroscope output after calibrating by the proposed calibration scheme is reduced by about 5% Compared with the traditional calibration scheme. Furthermore, online calibration of outfield environment is achieved without storing all the experimental data.