基于方位装订的弹载捷联惯导初始对准技术研究

Study on Initial Alignment Technology of Onboard SINS Based on Azimuth Setting

研究了基于方位装订的弹载捷联惯导系统的初始对准问题。首先推导了方位角误差和失准角误差的关系,在此基础上,提出了增加方位角误差作为观测量的观测方程,建立了基于方位装订条件下的卡尔曼滤波方程,并用奇异值分解的方法分析了系统的可观测性和不可观测状态变量,结果表明陀螺漂移均可观测,而加速度计零偏均不可观测;计算机仿真结果表明该初始对准方法收敛速度快,对准精度高。

The initial alignment technology of onboard SINS based on azimuth setting was researched.First,the relationship between azimuth error and misalignment error was deduced.The observation equation by adding azimuth error as observable variable was introduced.The Kalman filter equation based on azimuth setting was designed.The observability and unobservable variables equation of the system were analyzed with the method of singular value decomposition.The result shows that all gyro drift is observable,all accelerometer bias is unobservable.Simulation results show that the initial alignment method has an advantage of high precision and fast convergent speed.