2-DOF PID control of four degrees of freedom robotic arm

In this study, the position of the end element of the robot arm with four degrees of freedom is controlled by the 2-DOF PID controller. The reference position values of the end point of robot arm are applied to the inverse kinematic equations, the reference position angles are determined and these angles are controlled in closed loop. Direct current (DC) motor is used for the movement of each joint of the robot arm in this study. The robot arm is modeled in the Matlab/SimMechanics environment. The robot arm is modeled in the RoboAnalyzer program and the required torques for each joint are determined and the DA motor is selected according to these torque values. The transfer function corresponding to the selected motor parameters is obtained and this function is added to model. The robot arm was controlled by both a classical PID controller and a 2-DOF PID controller. Both the classical PID and the 2-DOF PID parameters are determined by the particle swarm optimization method. When the results are analyzed, it's seen that 2-DOF PID controller performance is better than classical PID's. Key Words: Robot arm, Kinematics equations, Position control, PSO, 2-DOF PID