This paper addresses the cooperative path following the problem of ring-networked under-actuated autonomous surface vehicles on a closed curve. A cooperative guidance law is proposed at the kinematic level such that a symmetric formation pattern is achieved. Specifically, individual guidance laws of surge speed and angular rate are developed by using a backstepping technique and a line-of-sight guidance method. Then, a coordination design is proposed to update the path variables under a ring-networked topology. The equilibrium point of the closed-loop system has been proven to be globally asymptotically stable. The result is extended to the cooperative path following the lack of sharing of a global reference velocity, and a distributed observer is designed to recover the reference velocity to each vehicle. Moreover, the cooperative path following the presence of an unknown sideslip is considered, and an extended state observer is developed to compensate for the effect of the unknown sideslip. Both simulation and experimental results are provided to illustrate the effectiveness of the proposed cooperative guidance law for the path following over a closed curve.

中文翻译：

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协作路径跟踪环网欠驱动自主地面车辆：算法和实验结果


本文解决了闭合曲线上环网欠驱动自主地面车辆问题的协作路径。在运动学层面提出了协作制导律，从而实现对称的编队模式。具体来说，通过使用反步技术和视线制导方法，开发了喘振速度和角速率的单独制导定律。然后，提出了一种协调设计来更新环网拓扑下的路径变量。闭环系统的平衡点已被证明是全局渐近稳定的。结果被扩展到缺乏全局参考速度共享的协作路径，并且设计了分布式观测器来恢复每个车辆的参考速度。此外，考虑了未知侧滑存在后的协作路径，并开发了扩展状态观察器来补偿未知侧滑的影响。提供了仿真和实验结果来说明所提出的协作制导律对于闭合曲线上的路径跟踪的有效性。