一种提高车载定位定向系统定位精度的方法

在车载定位定向系统中,通常采用停车修正或引入GPS等外信息校正系统,这会降低陆地武器装备的战场生存能力和自主性。基于上述情况,分析了惯导系统以及与里程计构成的航位推算系统的误差模型,得出了惯导系统短时间内定位精度高以及航位推算系统定位误差随时间增长缓慢的规律。据此推导并提出了一种提高系统定位精度的方法,该方法不需要停车或外部信息,首先利用惯导系统对航位推算系统进行校正,估计出里程计标度因数误差和载车的安装误差并进行补偿;之后利用航位推算系统对惯导系统进行校正;采用加权函数对系统位置输出进行加权优化处理。理论分析和仿真实验表明利用此方法在2 min内能估计出里程计标度因数误差和载车的安装误差,估计精度在90%以上;加权后的位置输出精度在0.2%D(D为里程)以上。

Method of improving the positioning precision about inertial positioning and heading system for land vehicle

In order to ensure the battlefield survivability and autonomy of the weapons and equipments for land vehicle,an inertial positioning and heading system for land vehicle should not do zero-velocity update or use GPS as much as possible to improve the precision.In this paper,by studying the error models of navigation system,it is concluded that the errors of dead reckoning system changed slowly with time,though the system’s precision is high in short time.A method for improving the system precision was proposed.In this method,the errors of vehicle installing and odometer scale factor are estimated and compensated by inertial navigation system,and the inertial navigation system is corrected by dead reckoning system.The weight function is used to bring a better precision positioning.Theory study and simulation show that this method can estimate out the scale factor error and installing error by no more than 2 min,and the estimation precision can reach more than 90% of preset values,the weighted position errors are no more than 0.2% of mileage.