In this paper, an adaptive terminal sliding mode control scheme for an omnidirectional mobile robot is proposed as a robust solution to the trajectory tracking control problem. The omnidirectional mobile robot has a double-frame structure, which adsorbes on the aircraft surface by suction cups. The major difficulties lie in the existence of nonholonomic constraints, system uncertainty and external disturbance. To overcome these difficulties, the kinematic model is established, the dynamic model is derived by using Lagrange method. Then, a robust adaptive terminal sliding mode (RATSM) control scheme is proposed to solve the problem of state stabilization and trajectory tracking. In order to enhance the robustness of the system, an adaptive online estimation law is designed to overcome the total uncertainty. Subsequently, the asymptotic stability of the system without total uncertainty is proved with basis on Lyapunov theory, and the system considering total uncertainty can converge to the domain containing the origin. Simulation results are given to show the verification and validation of the proposed control scheme.

中文翻译：

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用于飞机皮肤检查的全方位移动机器人的鲁棒自适应终端滑模控制

在本文中，提出了一种适用于全向移动机器人的自适应终端滑模控制方案，作为轨迹跟踪控制问题的稳健解决方案。全向移动机器人采用双框架结构，通过吸盘吸附在飞机表面。主要困难在于存在非完整约束、系统不确定性和外部干扰。为克服这些困难，建立了运动学模型，利用拉格朗日方法推导出了动力学模型。然后，提出了一种鲁棒的自适应终端滑模（RATSM）控制方案来解决状态稳定和轨迹跟踪问题。为了增强系统的鲁棒性，设计了自适应在线估计律来克服总的不确定性。随后，基于李雅普诺夫理论证明了没有总不确定性的系统的渐近稳定性，考虑到总不确定性的系统可以收敛到包含原点的域。仿真结果显示了所提出的控制方案的验证和验证。