捷联惯导大方位失准角快速初始对准

Initial Alignment Method of Large Azimuth Misalignment in SINS

捷联惯导方位角快速性能优化问题,传统大方位失准角初始对准方位角收敛速度较慢,直接影响惯导系统的性能。为此提出一种无重置联邦滤波器的以速度误差和比力输出作为观测量的快速初始对准新算法。给出了捷联惯导系统非线性误差模型,并分析了两种观测量,建立了速度观测子滤波器和比力观测子滤波器,同时采用了相应的状态方程和观测方程。用三种方法进行了大方位失准角初始对准的数字仿真。仿真结果对比表明,新方法不仅使方位失准角收敛速度快,而且在加速度计噪声增大10倍的情况下,仍然具有极高的对准精度。

The tilt angle estimation rate of large azimuth misalignment in SINS is slow,and a new initial alignment method was proposed,which used both the velocity error and the force output as the measuring values based on federated Kalman filter.Firstly,the SINS nonlinear error model was educed.Then these two measurements were analyzed particularly.The models of velocity measurement sub-filters and force measurement sub-filters were established and the measurement equations were presented.At last,the initial alignment of large azimuth misalignment simulation is carried out.The results show that not only the convergence rate of azimuth estimation increase,but also the precision remarkably improves even in the condition that the accelerate output noise increases ten times.