Adaptive Fast Terminal Sliding Mode Control of A Suspended Cable-Driven Robot

Abstract

Increasing the speed and precision of operation in cable robots is crucial due to the flexibility of cables. On the other hand, due to the frequent dynamical uncertainties present in cable robots, providing a robust control method is necessary. The performance of the fast terminal sliding mode (FTSM) controller has been investigated in various systems, which ensures that the state of the system is rapidly converged to the equilibrium point at a finite time. In this paper, the FTSM controller has been developed in such a way to be able to track the optimal robot path in the presence of dynamic uncertainties at different operating speeds. The main innovation of this paper is to provide an adaptive robust control method for controlling cable robots and analyzing the stability of the closed-loop control system based on the Lyapunov stability theory. In order to demonstrate the effectiveness of the proposed controller, simulation results, as well as experimental implementation on ARAS-CAM, a four cable suspended robot with three degrees of freedom, has been investigated and it is shown that the proposed controller can provide suitable tracking performance in practice.