四轮车辆导航中的惯性/运动学模型组合方法

Inertial /Kinematics Integrate Method for Four-Wheel Vehicle Navigation

在车载导航系统性能优化问题的研究中,低成本INS误差随时间累积速率较快,但不能在较长时间内单独使用,需采用其它辅助手段抑制其误差累积。针对车载GPS/INS组合导航方案,GPS在恶劣环境下不可靠、甚至完全失效,从而失去对INS误差抑制作用的问题,提出一种利用车辆运动学模型辅助INS的方法。根据车辆运动学模型和非完整约束条件推算出车辆位置和速度信息,并利用推算信息辅助车载惯性导航系统,从而抑制纯惯导情况下导航误差迅速发散的问题。仿真结果表明,改进方法能将INS的误差抑制在一定范围内,同时,在引入非完整性约束条件后,车辆东向、北向速度误差有界。因而可以作为车载惯性导航系统在GPS失效时的一种有效辅助手段。

For the low-cost INS error accumulates rate faster over time, and cannot be used in a long time alone, other navigation methods are needed to restrain the error accumulation. However, the GPS/INS integrated vehicle navigation system, when GPS is not reliable or even completely fails in harsh environments, the restrain effects of in- ertial navigation system error will be lost. Aiming at this problem, this paper put forward a method using vehicle kine- matic model to aid inertial navigation system. In this method, the determine information of a vehicle＇s position and velocity was gained through a vehicle kinematic model and nonbolonomic constraint conditions. The determine infor- mation was used to aid vehicle inertial navigation system, thus easing the problem of the rapid divergence of INS error in a pure INS case. The MATLAB simulation results show that the error of the integrated navigation system can be in- hibited in a certain range, and after introducting nonholonomic, the constraint conditions of north and east speed er- rors were bounded. So it can be used as an effective aided method for vehicle navigation system when the GPS outage.