从地心地固系中卡尔曼滤波方程的推导入手,设计了一个12状态滤波器,对失准角进行估计,在地心地固坐标系中完成了惯导的初始精对准。模拟计算证明了此算法的正确性与有效性,并讨论了对准的精度。
Inertial navigation system fine alignment based on Kalman filter is normally carried out under navigation frame.Earth-centered-earth-fixed(ECEF) frame is an important frame for combination navigation and inertial geodesy but no previous research has been shown for the fine alignment under this frame.Beginsing from mathematical deduction of a 12-states Kalman filter equation under ECEF frame,we estimate the misalignment angles and determine the transformation matrix from body frame to ECEF frame for the fine alignment.A simulation calculation is accomplished for this algorithm to prove its validity and availability.Besides,the alignment accuracy is also discussed.Experimental results show that the fine alignment can also be done under ECEF frame for inertial navigation system.