基于不同坐标系下速度量测的捷联惯导系统晃动基座对准研究

Research on Initial Alignment of SINS on Swaying Base through Velocity Measurement in Different Coordinates

为解决晃动基座下杆臂效应对捷联惯导系统对准的不利影响问题,以捷联惯导系统解算速度与杆臂速度之间的差值作为量测量,扩充杆臂长度误差为系统状态量,分别推导建立导航系和机体系下的量测方程,构成两种对准模型。分析两种对准模型的特点,指出导航系下对准模型仅适用于能够获得一定精度杆臂长度的情形。在此基础上,提出滤波参数反馈修正的滤波方法,以提高对准模型的适应性和对准精度。仿真实验验证了两种对准模型的正确性和滤波参数反馈修正滤波方法的有效性。

Two alignment models are proposed to solve the adverse effect of lever arm on initial alignment of strapdown inertial navigation system （SINS） on a swaying base.In the proposed method,the difference between SINS output velocity and lever arm velocity is taken as a measurement and two measurement equations are established separately for navigation frame and body frame.The characteristics of the two alignment models are analyzed.It is demonstrated that the alignment model in navigation frame is only suitable for the case of having lever arm length with a certain precision.On this basis,a filtering method for feedback correction of filter parameters is presented to improve the adaptability of the alignment models and the alignment accuracy.The simulation results show that the two alignment models are available,and the filtering method is effective for feedback correction of filter parameters.