捷联惯导系统单轴旋转调制误差传播机理研究

为了抑制捷联惯导定位误差的累积,提高捷联惯导定位精度、姿态精度和速度精度,分析了捷联惯导系统在单轴旋转调制下的误差传播机理,推导了多误差源同时激励下旋转调制捷联惯导系统的误差传播模型及各个误差项的复频域表达式,讨论了旋转调制速率的选取原则。仿真结果表明,采用旋转调制技术后,陀螺仪的常值漂移、加速度计的零偏引起的导航误差可以得到有效补偿,选取旋转频率时,应避免旋转频率接近舒勒调谐频率、傅科频率和地球自转频率,否则导航误差反而会增大。

Research on Mechanism of Error Propagation for SINS with Rotating Modulation Technology

In order to suppress the accumulation of position errors,improve the position accuracy as well as attitude and velocity accuracy,the mechanism of error propagation for Strapdown Inertial Navigation System with rotating modulation technology is analyzed in detail,and the simulation results are given in the paper. The mathematical model of propagation of errors aroused by all error sources is given and the expressions in frequency-domain are deduced. The position and attitude error is analyzed,which is aroused by bias of gyros and accelerators,initial velocity error,initial position error and initial attitude error. How to determine the rotary speed is discussed in this paper. The results of simulation show that error aroused by bias of gyros and accelerators can be weakened. The rotational frequency can not be equal to schuler tuning frequency,foucault frequency and frequency of earth rotation,or else the error will increase.