A Two-Link Robot Manipulator: Simulation and Control Design

Abstract

In this paper, we design a robust, fast, and practical proportional-integral-derivative (PID) controller for the classical double pendulum system. We first derive the equations of motion for the two-link robot manipulator using the Lagrangian approach. These equations are described by nonlinear system of ordinary differential equations. Because closed form solutions of the equations of motion are not available, we use the classical fourth-order Runge-Kutta method to approximate the solution of the initial-value problem. Because of the nonlinear behavior, it is a challenging task to control the motion of the two-link robot manipulator at accurate position defined by the user. For this, we focus mainly on control of the robot manipulator to get the desired position using the computed torque control method. After deriving the equation of motion, control simulation is represented using MATLAB. Several computer simulations are used to verify the performance of the controller. In particular, we present a PID controller to simulate how we would balance the two-links on a moving robot to any specific angle including upside-down.