Designing a PID controller for a ۲-DOF robotic arm using differential evolution algorithm

Modeling and controlling have a vital role in automation. The modeling problem before implementing the control system is essential for guaranteeing the performance of the system according to the input with the minimum error. Therefore, solving the Newton-Euler dynamic equations is the first step in modeling the manipulation arm. In this research, a proportional-integral-derivative (PID) controller is designed for the planar robot with ۲ degrees of freedom in which the coefficients are enhanced through a differential evolution algorithm. The differential evolution algorithm is a new heuristic algorithm which uses three advantages including finding the actual global minimum without considering the initial values of the parameters, fast convergence and using multiple control parameters. The proposed method calculates the cost function through differential evolution (DE) and particles swarm optimization (PSO) algorithms in order to adjust the PID controller parameters. The simulations show that the proposed DE-PID controller has a better and stronger performance compared to that of the PSO-PID controller in controlling the robot path with the minimum error. Also, the capability of the system was tested through applying a weighted disturbance for which the simulation results show the capability of the system in identifying and compensating the impact of the disturbance.

Keywords:

Planar robot , DE-PID controller , DE algorithm