Design of Classic and Fuzzy PID, PD, and PI Controllers for Control of a Bascule Lift Mechanical Arm

The science of robotics has been widely applied to develop industries and specifically to reduce human injuries. By adjusting the controller of these robots to achieve proper speed and accuracy, their performance can be improved which it can lead to reduction in the number of injuries. Until now, robotic arm controllers have often been modeled using equations of direct and inverse kinematics, aiming to control the position of the final actuator of the arm. Difficulty in solving these equations, errors in solving them, lack of user-friendly environment, inflexibility in decision-making and the volume of calculations are among the problems of existing robotic control systems. In this paper, the robotic arm with four degrees of freedom is controlled by two classic and Fuzzy control methods and three PI, PD and PID controllers. Matlab-Simulink is used as a tool to test the movement characteristics of the robot. It was observed that the PD controller, despite not having overshoot, leads to a steady state error in most of the cases. Also, the PI controller provides a proper settling time, while, it has a higher overshoot than the PID controller. Finally, the results showed that the Fuzzy PID controller provides better responses than the classical PID controller and the classical and Fuzzy PI and PD controllers.