对里程计辅助的车载激光捷联惯导系统(SINS)的动基座初始对准问题进行了可观测性分析。首先,考虑里程计刻度系数误差、惯性测量单元零偏、SINS安装误差角等系统误差项建立了系统方程。然后,从系统方程出发,将系统可观测性问题转化为判断系统状态量是否存在唯一解的问题,利用全局可观测性分析方法对系统状态进行了可观测性分析,并给出了一种系统可观测的充分条件。最后,根据可观测性分析结论设计了初始对准算法及在轨激励方式。通过扩展卡尔曼滤波器对里程计辅助的车载激光SINS初始对准进行了计算机仿真,仿真结果验证了理论分析结果的正确性。

The observability analysis of the initial alignment problem of the vehicle-based-laser strapdown inertial navigation system (SINS) aided by odometer is carried out. First, the system equation is established by considering the system error items including the odometer scale factor error, inertial measurement unit zero bias, SINS misalignment error angle, etc. Then, starting from system equation, the system observability problem is transformed to the determination of whether there is a unique solution to the state variables of the system. The observability analysis of the system state is conducted by the global observability analysis method, and requirements for maneuvering is given to ensure that the system is observable. Finally, the initial alignment algorithm method and on-track incentive mode are designed according to the results of observable analysis. The simulation of odometer aided laser SINS in-motion initial alignment is conducted by extended Kalman filter, and the simulation results verify the validity of the theoretical analysis.