Smooth second-order sliding mode controller for multivariable mechanical systems

• Main Authors: Panitnart Chawengkrittayanont, Chutiphon Pukdeboon, Suwat Kuntanapreeda, Elvin J. Moore
• Format: Article
• Language: English
• Published: Springer 2021-09-01
• Series: SN Applied Sciences
• Subjects: Finite-time convergence; Second-order sliding mode control; Smooth sliding mode control; Multi-input multi-output system
• Online Access: https://doi.org/10.1007/s42452-021-04800-4

Abstract This paper proposes a smooth second-order sliding mode controller for a class of multi-input multi-output mechanical systems with uncertain parameters and external disturbances. Since the control law is smooth, the chattering effect that can occur with non-smooth controllers is reduced. Lyapunov-based theorems are used to prove global and finite-time convergence of the sliding mode controller. Numerical simulations are presented to illustrate the performance of the proposed controller by applying it first to a variable-length pendulum and then to a two-link robotic manipulator. For the robotic manipulator, a detailed comparison is given of the finite-time convergence and chattering properties of the proposed controller, a super-twisting controller and a super-twisting like controller. Article Highlights A new smooth second-order sliding mode controller is proposed for multivariable systems with uncertain parameters and external disturbances. Global finite-time convergence of the controller is proved using Lyapunov theory. Numerical simulations are used to show the performance of the controller on the variable-length pendulum and two-link robotic manipulator.