Robust Nonsingular Fast Terminal Sliding Mode Control in Trajectory Tracking for a Rigid Robotic Arm

Abstract

In this paper, a novel concept of robust Nonsingular Fast Terminal Sliding Mode controller (NFTSMC) is adopted for the trajectory tracking problem of a non-linear system. The developed controller is based on NFTSM controller and $${{{\text{H}}}_{\infty }}$$ approach. The use of the NFTSM controller offers a fast convergence rate, avoids singularities, but still suffers from chattering. In order to overcome this limitation, a new term in the control law is inspired by the technique of $${{{\text{H}}}_{\infty }}{\text{;}}$$ it interferes by managing uncertainties and external disturbances without knowing their upper bound. Stability analysis of the closed-loop system is accomplished using the Lyapunov criterion. Several simulation results are given to show the effectiveness of the proposed approach.