车载单天线GPS/MEMS-SINS组合对准算法

Study of Integrated Alignment Algorithm for MEMS-SINS with Single GPS Antenna Used in Vehicle Navigation

捷联式惯性导航系统(SINS)需要精确的初始姿态信息进行姿态、速度和位置解算,而微机电系统(MEMS)惯性传感器由于精度限制无法完成自对准。为了解决这个问题,提出一种基于单天线GPS测姿和MEMS-SINS的组合对准算法。采用单天线GPS在载体稳定协调运动条件下给出粗略的航向角信息,进行姿态粗对准。在精对准阶段,使用GPS提供的载体的航向角、位置和速度信息作为观测量,建立Kalman滤波器,对捷联式惯性系统的误差项进行估计,得到精确的姿态矩阵(DCM),完成对准。经过仿真和车载试验验证,对准后的俯仰角和横滚角均方误差在0.1°内,航向角均方误差在0.5°以内。表明算法可以在运动条件下完成载体的对准要求,有一定的实用价值。

An accurate initial attitude information is required for strapdown inertial navigation system （SINS） to do the resolution of attitude, velocity and position. However, the inertial sensor based on micro-electromechanical system （MEMS） is unable to achieve a self-alignment because of its low resolution. Therefore, an integrated alignment algorithm is proposed to solve this problem. Under the condition of carrier moving, a single GPS antenna is used to give a rough azimuth for the coarse alignment. During the precision alignment stage, a Kalman filter is established by using the azimuth, velocity and position of the carrier provided by GPS as the measurement information to estimate the error term of the SINS and get an accurate di- rection cosine matrix （DCM） to complete the alignment. The simulation and vehicle test show that the pitch and roll mean square errors are under 0.1° and azimuth mean square error is under 0. 5° after the alignment, which indicates that the algo- rithm is able to meet the requirement of initial alignment for the vehicle and has practical value for SINS initial alignment.