惯性测量单元输出信号的精度直接影响捷联惯性导航系统的精度,为了提高捷联系统的精度,以舰船光纤捷联惯性航姿系统为应用对象,采用了双轴旋转机构连续匀速旋转IMU的系统方法,把惯性测量单元输出信号中的漂移误差调制成正弦信号,通过捷联算法中的积分运算可以有效地消除陀螺和加速度计中的漂移误差,从而有效地提高捷联惯性航姿系统的精度,并进行了系统仿真实验。仿真结果表明:经过旋转以后的IMU输出信号误差较传统非旋转方法可以减小一个数量级。基于双轴旋转IMU的系统方法可以有效地减小IMU输出信号漂移误差和提高捷联惯性航姿系统的精度。
The high accuracy of Strapdown Inertial Navigation System is greatly attributed to the precision of inertial measurement unit (IMU). Dual-axis IMU rotation method which modulated the IMU random drift error into periodical variable sine signal was applied in the ship Fiber Optic Gyroscope (FOG) Strapdown Attitude and Heading Reference System for improving the navigation accuracy of SINS. The randon drift error can be eliminated effectively with the integration of strapdown attitude algorithm. The simulation experiments of the system were carried out which show that the drill error is reduced greatly by the method. Dual-axis IMU rotation method is effective in eliminating the IMU drift error and improving the strapdown inertial attitude and heading reference system precision.