双轴旋转式惯导系统自标校技术

Self-calibration in dual-axis rotary inertial navigation system

为使系统长时间保持较高精度,惯导系统启动后需要对惯性器件误差进行标校.本文利用全局可观测性分析方法,建立了旋转式惯导系统的运动状态与其可观测性之间的关系,提出船用旋转式捷联惯导初始对准与自标校的转位原则,利用该原则并结合惯导系统的实际,设计出了一种绕两水平轴旋转的八位置标校方案,仿真结果表明绕两水平轴旋转方案优于其他绕任意两轴旋转方案;在实验室环境下对该标校方案进行了试验验证,结果表明:采用该方案后系统的定位误差由18 nm/10 h减小到5 nm/10 h,系统定位精度大幅度提高,验证了该标校方案的有效性.

The inertial sensor errors should be calibrated when strapdown inertial navigation system （SINS） restarts to maintain the high accuracy for a long time. In this paper, we use the global observability analysis method to build up the relationship between the motion status and the system observability. The rotating principle of SINS initial alignment and self-calibration is also proposed. An eight-position rotating method which rotates around the two horizontal axes is designed based on the principle. The simulation results show that the rotating method which rotates around the horizontal axis has a better performance than that rotates around the any other two axes. At last the experiment results show that the location accuracy is enhanced to 5 ran/10 h from 18 nm/10 h with the eight-position calibration method, which verifies the effectiveness of this new rotating method.