基于无轨迹卡尔曼滤波的大失准角INS初始对准

Application of Unscented Kalman Filter for Large Misalignment Errors in INS Alignment

讨论了大失准角情况下,惯性导航系统(INS)初始对准的非线性误差模型,分析了无轨迹卡尔曼滤波原理,提出将无轨迹卡尔曼滤波(UKF)技术应用于惯性导航系统初始对准ψ角估计中,进行了静基座状态下的初始对准仿真。仿真结果表明,在方位误差角为大角度,水平误差角为小量的情形下,无轨迹卡尔曼滤波比扩展卡尔曼滤波(EKF)对准时间更快,估计精度更高。当ψ角三个分量均为小量时,无轨迹卡尔曼滤波也具有很好的性能。

The psi-angle model of nonlinear inertial navigation system （INS） alignment for large misalignment error was discussed, and the principle of the unscented Kalman filter （UKF） was analyzed. The UKF was used to estimate the psi-angle of INS alignment and simulation for the INS alignment on stationary base is presented. Simulation results show that the UKF is faster in alignment time and more accurate in estimation precision than the EKF in the case of large uncertainties in heading and low uncertainties in tilt angle. The UKF has better performance for low uncertainties of three psi-angles too.