AUV协同定位性能与编队构型分析

针对三领航艇自主水下航行器(AUV)协同导航系统,在不简化距离量测方程的前提下推导系统定位性能评价函数,在此基础上分析系统定位性能与编队构型、集群航速以及艇间距离之间的耦合关系。同时,通过理论分析证明在一定条件下该系统定位性能评价函数可以退化为最简形式,且该最简定位性能评价函数与误差椭圆法、Fisher信息矩阵法相关结果在表达形式上具有一致性。进一步,通过推导AUV位置估计的克拉美-罗下界(CRLB)完善系统定位性能评价函数并定量分析艇间测距噪声对系统定位性能的影响。最后,基于系统定位性能评价函数分析构建三领航艇协同导航系统最优、次优与最差编队构型,并通过仿真实验证明分析结论与编队构型的有效性。仿真实验结果表明,当AUV集群以最优、次优编队构型航行时,降低集群速度可以在一定程度上提高系统定位性能,在本文设置实验条件下系统定位精度可以提高9.11%,但改变艇间距离对定位性能几乎没有影响;当AUV集群以最差编队构型航行时,降低集群速度与缩短艇间距离均可提高系统定位性能,若两者同时满足将大幅提高系统定位性能,在本文设置实验条件下系统定位精度分别提高63.17%、63.99%与81.50%。

Analysis of localization performance and formation configuration for AUV cooperative navigation

To achieve a cooperative navigation system for multiple autonomous underwater vehicles(AUVs)with three leaders,the localization performance evaluation function is derived without simplifying range measurement equation. In this way, the relationship among localization performance,formation configuration,cluster speed and distance between AUVs is analyzed. Theoretical analysis proves that the localization performance evaluation function can be degeneratedinto the simplest form under certain conditions,and the localization performance evaluation function in the simplest form is consistent with the corresponding results of theerror ellipse method and the Fisher information matrix method. Furthermore, Cramer-Rao lower bound based on localization estimation is derived to improve localization performance evaluation function, and the influence of rang measurement noise on the localization performance is analyzed. Finally, the optimal formation configuration, the suboptimal formation configuration and the worst formation configuration are constructed based on localization performance evaluation function analysis for the three-leaders cooperative navigation system, and the effectiveness of analysis and formation configuration is evaluated by simulation experiments. The results show that reducing cluster speed can improve the localization performance of system in the optimaland suboptimal formation configuration to a certain extent. Under the simulation conditions, the accuracy of localization can be increased by 9.11%. However, changing distance between AUVs has almost no effect on the localization performance. For a cooperative navigation systemin the worst formation configuration, reducing cluster speed and shortening distance between AUVs can both improve the localization performance. If they are both satisfied, the localization performance will be greatly improved. Under the simulation conditions,the accuracy of localization is increased by 63.17%,63.99%,and 81.50%,respectively.