Hybrid PD/PID controller design for two-link flexible manipulators

This paper investigates the development of a hybrid collocated PD and non-collocated PID controller designed for input tracking and vibration control of two-link flexible manipulator. The two-link robot manipulator was modelled using Lagrange and assumed mode method. The PD controller is used for motion tracking and the PID for vibration control. Effect of changing controller gains on performance is studied using two case studies. Also studied is the effect of payload variation on the performance of the proposed controller. The performance of the designed controllers is evaluated in terms of input tracking capability, energy utilization, deflection suppression and vibration control. Results show that a simple PD-PID controller can be effectively designed for point-to-point motion control and vibration suppression for two link flexible manipulators. Also the study reveals that the controller is robust to payload variation.