Cooperative tracking control problem of multiple water–land amphibious robots is discussed in this article with consideration of unknown nonlinear dynamics. Firstly, the amphibious robot dynamic model is formulated as an uncoupled nonlinear one in horizontal plane through eliminating relatively small sway velocity of the platform. Then cooperative tracking control algorithm is proposed with a two-stage strategy including dynamic control stage and kinematic control stage. In dynamic control stage, adaptive consensus control algorithm is obtained with estimating nonlinear properties of amphibious robots and velocities of the leader by neural network with unreliable communication links which is always the case in underwater applications. After that, kinematic cooperative controller is presented to guarantee formation stability of multiple water–land amphibious robots system in kinematic control stage. As a result, with the implementation of graph theory and Lyapunov theory, the stability of the formation tracking of multiple water–land amphibious robots system is proved with consideration of jointly connected communication graph. At last, simulations are carried out to prove the effectiveness of the proposed approaches.

中文翻译：

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非线性动力学未知的多台两栖机器人编队跟踪

本文在考虑未知非线性动力学的情况下讨论了多个水陆两栖机器人的协同跟踪控制问题。首先，通过消除平台相对较小的摇摆速度，将两栖机器人动力学模型表述为水平面内的非耦合非线性模型。然后提出了动态控制阶段和运动控制阶段两阶段策略的协同跟踪控制算法。在动态控制阶段，自适应一致性控制算法是通过神经网络估计两栖机器人的非线性特性和领导者的速度来获得的，这种神经网络在水下应用中经常遇到不可靠的通信链路。之后，为保证多水陆两栖机器人系统在运动控制阶段的编队稳定性，提出了运动协同控制器。结果，应用图论和李雅普诺夫理论，证明了考虑联合连通通信图的多水陆两栖机器人系统编队跟踪的稳定性。最后，通过仿真验证了所提出方法的有效性。