在反转平台离心机上标定陀螺仪的误差模型系数的方法

Calibration of gyro error model coefficients on precision centrifuge with counter-rotating platform

为了准确标定陀螺仪的静态误差模型系数,在带反转平台的精密离心机上建立坐标系,并在考虑离心机误差源的情况下分析了坐标系间的姿态关系。推导出了陀螺仪各轴上精确的角速度输入和比力输入标称值,再结合陀螺仪静态误差模型推导出含有陀螺仪漂移系数的各次谐波幅值表达式。通过离心机提供两个不同谐波加速度,采集陀螺仪各采样时刻的输出,对输出应用谐波分析法求得0-2次谐波幅值大小,再根据谐波幅值与漂移系数之间的关系,利用最小二乘法辨识各漂移系数。试验仿真表明采用带反转平台的离心机对陀螺仪漂移系数标定时可以有效规避某些离心机误差,离心机误差对于DI、DS、DIO和DOS等参数的标定有很大影响,须在补偿离心机误差的情况下才能够实现精确标定。

In order to accurately calibrate the gyro drift coefficients,a coordinate system was set up based on the precision centrifuge with counter-rotating platform,and the attitude relationship between two adjacent coordinate systems were analyzed in consideration of the error sources.Precise angular velocity input for each axis of gyro was derived by using direction cosine matrices,and the nominal value of each specific force input was given as well.Combined with the gyro’s static error model,various harmonic amplitude expressions were deduced including gyro drift coefficients.By using centrifuge to provide two different harmonic accelerations,and sampling the output of gyro at each sampling time,the amplitudes of 0-2nd harmonics were obtained through Fourier analysis.The drift coefficients were identified by least square method based on the relationship between harmonic amplitude expressions and drift coefficients.The test simulation results show that the calibration of the gyro drift coefficients on centrifuge with counter-rotating platform can effectively avoid some of the centrifuge errors,and other centrifuge errors only have significant impacts on DI,DS,DIO and DOSwhose accurate calibration can be achieved by compensating the centrifuge errors.