Predefined-time Terminal Sliding Mode Control of Robot Manipulators

TL;DR

This paper introduces a novel predefined-time terminal sliding mode control for robot manipulators, ensuring convergence within a user-defined time regardless of initial conditions, and demonstrating robustness against disturbances and uncertainties.

Contribution

It develops a new control method with a predefined-time sliding surface, providing explicit convergence time and robustness, supported by theoretical analysis and simulations.

Findings

Achieves predefined-time stability independent of initial conditions

Provides robustness against external disturbances and parametric uncertainties

Validated through theoretical analysis and numerical simulations

Abstract

In this paper, we present a new terminal sliding mode control to achieve predefined-time stability of robot manipulators. The proposed control is developed based on a novel predefined-time terminal sliding mode (PTSM) surface, on which the states are forced to reach the origin in a predefined time, i.e., the settling time is independent to the initial condition and can be explicitly user-defined via adjusting some specific parameters called the predefined-time parameters. It is also demonstrated that the proposed control can provide satisfactory steady-state performance in the case of both external disturbances and parametric uncertainties. Besides, we present a formal systemic analysis method to derive the sufficient conditions for guaranteeing the predefined-time convergence of the closed-loop system. Finally, the effectiveness and performance of the presented control scheme are illustrated through both theoretical comparisons and numerical simulations.