Performance comparison between PD and PID Controller in an upper limb Exoskeleton by analyzing an arm trajectory modeled with Image Recognition

This paper presents a performance comparison between PD and PID controllers of a 3-DOF (3 Degrees of Freedom) upper-limb exoskeletons by analyzing an arm trajectory during a rehabilitation task. Trajectory was recorded and modeled by an image recognition algorithm for its identification. 2-DOF were considered and associated with the shoulder and the elbow joints. The trajectory, used in rehabilitation, is based on a basic activity of daily life. By using the collected data, we obtained the tracking error variance of PD and PID controllers for each body joint in the arm in order to make a suitable performance comparison according to quantitative results. Besides, this study is relevant because this sort of robotic system aims to assist patients by allowing more reliable and fast recovery of arm mobility.