基于UWB辅助的多无人机惯导定位误差校正方法

Error Correction Method of Multiple UAV Inertial Navigation Based on UWB

摘要:

针对卫星导航拒止的复杂环境下多无人机编队飞行只依赖惯性导航无法长时间导航的问题，提出一种超宽带（Ultra Wide Band，UWB）辅助的惯导定位误差校正方法。给出UWB测距原理的同时建立了无人机机体坐标系下的惯导相对距离解算模型；在惯导误差模型的基础上，以惯导误差和UWB测距信息分别作为状态量和观测量，设计出惯导误差校正的扩展卡尔曼滤波模型；以两架无人机为例对算法进行仿真验证，仿真结果表明相较于纯惯导定位，该方法在东北天三个方向的最大定位误差不超过1 m，速度均方根误差值不超过0.01 m/s，很好地抑制了惯导系统速度和位置的误差发散，为解决无人机编队在卫星拒止环境中的定位问题提供参考思路。

Abstract:

Aiming at the problem that multi-UAVs cannot navigate for a long time when they are flying in formation only relies on inertial navigation in complex environment where satellite navigation is restricted, a positioning error correction method based on ultra wide band (UWB) assisted inertial navigation is proposed. The principle of UWB ranging is given, and the relative distance calculation model of inertial navigation in the UAV body coordinate system is established. Based on the inertial navigation error model, the Extended Kalman filter model of error correction is designed by taking the inertial navigation error and the UWB distance measurements as the state quantity and the observation quantity respectively. Simulation and verification of the algorithm using two unmanned aerial vehicles as examples, the results show that compared with the pure inertial navigation system, the maximum positioning error of this method is less than 1m in the three directions of ENU, and the root mean square error of velocity is not more than 0.01 m/s. This method effectively inhibits the error divergence of the velocity and position with inertial navigation, and provides a reference for solving the positioning problem of multi-UAVs formation flying in the satellite rejection environment.