Design and Implementation of Second Order Sliding Mode Controller for 2-DOF Flexible Robotic Link

Abstract

This paper presents design and practical implementation of robust super twisting type Second Order Sliding Mode (SOSM) controller for an under actuated 2-DOF flexible link manipulator system. The flexible link system resembles to a robotic arm having two flexible links governed by two DC motors. The mathematical model of the system is derived using Euler-Lagrange formula. A goal of Super Twisting (ST) controller is to regulate the position of both arms simultaneously having coupling effect. The STA of SOSMC attenuate the chattering effect that predominates in the classical sliding mode controller. The efficacy of the controller is checked in both simulation as well experimentally. The simulation is carried out using MATLAB R2016. The experiment is carried out on a laboratory setup using QUARC software (for hardware interfacing) and MATLAB R2016. The simulation as well experimental results are compared with conventional LQR controller and classical f-order sliding mode controller. The results endows that the 2-order SMC controller outperforms the other controllers.