MEMS器件捷联惯导系统旋转调制技术

Rotation Modulation for Strap-Down Inertial Navigation System Based on MEMS Sensors

使用微机电(MEMS)惯性器件利于捷联惯导系统的低成本和小型化,但MEMS器件误差较大.为提高系统精度,引入了一种全自主误差补偿方法——旋转调制.说明了旋转调制对常值误差的抑制作用和对导航精度的改善效果,并在旋转轴数目、旋转方向、旋转连续性和旋转速度等方面比较了不同旋转调制方案.根据MEMS器件的误差特性,选择了一种适合MEMS器件捷联惯导系统的旋转调制方案并自主研发了原理样机.静态和车载实验表明:旋转调制可以明显抑制MEMS器件常值误差对导航精度的影响,200 s内俯仰和横滚姿态精度提高了5倍,速度和位置精度提高了近10倍.

MEMS inertial sensors benefit the low-cost and miniaturization of strap-down inertial navigation system, but their errors are large. To improve the navigation performance, a systematic error auto-compensation method--rotation modulation （RNI）was introduced. The RM effects on restraining constant biases and improving navigation accuracy were elaborated. The rotation modulation schemes including the number of rotating axis, rotation direction, rotation continuity and rotation speed were compared. Based on the error characteristics of MEMS sensor, an appropriate rotation scheme was determined for that and a prototype was self-developed. Static and land vehicle experiments showed that RM can greatly improve the navigation performance by constraining the constant biases of MEMS sensors. The attitude accuracy is 5 times better and velocity/position accuracy is nearly 10 times better in 200 s.