Position Control and Vibration Suppression of a Two-Link Manipulator Using DC Motors and Piezoelectric Patches

Flexible manipulators are increasingly used in robotics and aeronautics, due to their ability to reduce the weight and energy consumption of the system; however, their bandwidth is lower than their rigid counterparts. To obtain acceptable performance, as a substitute of rigid manipulators, vibration of these manipulators has also to be controlled. Position control and vibration suppression of a two-link flexible manipulator with a hybrid actuator of DC motors and piezoelectric patches is presented in this paper. The piezoelectric patches serve as high frequency sensors and actuators. The proposed system enables the robot to perform high rate and high frequency movements simultaneously. The equations of motion are written based on extended Hamilton’s principle. Due to the complexity of the equations, fuzzy controllers are used to control the position (high rate trajectory tracking) of the manipulator. PD controllers are used to suppress the vibration (control the high frequency movements) of the links. Numerical simulation is presented to verify the performance of the controllers. The results prove that the proposed system can control the position and vibration of the links effectively.

Keywords:

Flexible manipulator , Vibration Control , Piezoelectric Patches , Fuzzy control