箭载SINS快速自对准技术

为适应运载火箭快速发射需求，捷联惯导系统采用自对准技术逐渐取代了复杂的光学瞄准系统。针对初始对准中Kalman滤波器收敛缓慢的问题，提出了基于低通滤波的运载火箭快速自对准方法。该方法基于凝固惯性系自对准算法，采用移动窗双矢量构造方案，实现了自对准实时解算。通过在凝固惯性系间姿态转换矩阵后端引入低通滤波器，降低杆臂效应引起的有害加速度影响，保证自对准精度。该方法不需要进行复杂的Kalman滤波运算，能够快速收敛，工程实现简单。数字仿真和试验数据表明，采用基于低通滤波的凝固惯性系自对准方法可以达到Kalman滤波对准同等级精度的同时缩短对准时间到5min以内，验证了该方法的有效性。

Rapid Self-alignment Technology of SINS for Launch Vehicle

In order to meet the requirements of launch vehicle, the SINS has gradually replaced the complex optical aiming system with self-alignment technology. Aiming at the problem that the Kalman filter converges slowly in the initial alignment, a rapid self-alignment method for launch vehicle based on low-pass filter is proposed. Based on the self-aligning algorithm of the solidification inertial frames, the self-alignment real-time solution is realized by using the two-vector construction scheme of the moving window. A low-pass filter is introduced at the rear end of attitude transfer matrix between solidified inertial frames to reduce the harmful acceleration caused by the lever arm effect and ensure the self-alignment accuracy. The method does not need to carry on complex Kalman filter operation and converges quickly. It is also simple to realize engineering. Digital simulation and experiment data show that the self-alignment method of the solidification inertial frames based on low-pass filter can achieve the same accuracy of Kalman filter and shorten the alignment time within 5min. Finally, these results show the validity of the method.