车载低精度INS/GPS大方位失准角线性对准研究

Study on the Linear Alignment of Large Heading Uncertain Alignment of Vehicle Low Precision INS/GPS

在应用低精度微机电系统-惯性测量单元(MEMS-IMU)和全球定位系统(GPS)的车载组合导航中,由于IMU的精度问题,无法通过传统的解析方法实现方位失准角的粗对准,造成了大方位失准角问题。该文通过变换状态量,用方位失准角的两个三角函数代替方位失准角作为状态量,建立了新的线性系统方程,统一了精对准和粗对准的过程,避免了粗对准切换到精对准时状态间的协方差信息损失。完成了车载导航试验。结果表明,本初始对准方案在低精度的组合导航中能将对准精度控制在1°以内。

The convent ional al ignment method cannot be appl ied to the vehicle navigat ion due to the low per form-ance of IMU, which causes the problem of large heading uncertain alignment. In this paper, two trigonometric func-tions of the heading uncertain angle are used as the quantity of state to establish the a new linear system equation. On the other hand, the coarse and fine alignment procedures are unified to avoid the covariance information loss dur-ing the switching from the coarse alignment to the fine alignment. The vehicle test results verified the heading error of the new alignment method can be lower than 1°.