随机游走对罗经方位对准的精度影响分析

分析了随机游走对罗经方位对准的影响,通过罗经方位对准的频域误差传递函数,求出时域的单位脉冲响应函数,进而推导出该系统在白噪声驱动下的时域表达式,最后求出该表达式的统计特性,其标准差即为随机游走对罗经方位对准的误差公式。通过分析误差公式可知,罗经方位对准的精度与随机游走系数成正比,还与设置的半个二阶阻尼振荡周期的平方根成反比。当陀螺随机游走一定时,单纯的通过延长对准时间并不能提高对准精度,还需要延长二阶阻尼振荡周期,数值仿真验证了所提观点的正确性。

Effect of angle random walk on compass azimuth alignment

The effect of angle random walk (ARW) on compass azimuth alignment is analyzed.The time-domain impulse response function is obtained by frequency-domain error transfer function of azimuth alignment,and the time-domain expression of the system under white noise is deduced.Finally,the statistical properties of the time-domain expression are obtained,which show that the standard deviation is the error formula of ARW to the compass azimuth alignment.The analysis on the error formula show that the accuracy of compass azimuth alignment is directly proportional to the ARW coefficient,and is inversely proportional to the square root of the half-order second-order damped oscillation period.When the gyro's ARW is constant,the alignment accuracy can't be improved only by prolonging alignment time,and the second-order damping shock period is also needed to be extended.The numerical simulation verifies the correctness of the above conclusion.