Fast Finite-Time Sliding Mode Control for Chattering-Free Trajectory Tracking of Robotic Manipulators

TL;DR

This paper introduces a novel chattering-free finite-time sliding mode control method for robotic manipulators, significantly improving trajectory tracking accuracy, robustness, and convergence speed while reducing chattering effects.

Contribution

The paper proposes an improved sliding surface and control strategy that effectively mitigates chattering and ensures finite-time convergence in robotic arm trajectory tracking.

Findings

Superior tracking accuracy demonstrated in simulations

Faster convergence compared to traditional methods

Enhanced robustness against disturbances

Abstract

Achieving precise and efficient trajectory tracking in robotic arms remains a key challenge due to system uncertainties and chattering effects in conventional sliding mode control (SMC). This paper presents a chattering-free fast terminal sliding mode control (FTSMC) strategy for a three-degree-of-freedom (3-DOF) robotic arm, designed to enhance tracking accuracy and robustness while ensuring finite-time convergence. The control framework is developed using Newton-Euler dynamics, followed by a state-space representation that captures the system's angular position and velocity. By incorporating an improved sliding surface and a Lyapunov-based stability analysis, the proposed FTSMC effectively mitigates chattering while preserving the advantages of SMC, such as fast response and strong disturbance rejection. The controller's performance is rigorously evaluated through comparisons with conventional PD sliding mode control (PDSMC) and terminal sliding mode control (TSMC). Simulation results demonstrate that the proposed approach achieves superior trajectory tracking performance, faster convergence, and enhanced stability compared to existing methods, making it a promising solution for high-precision robotic applications.