Active vibration control of flexible two-link manipulator
University of New Brunswick
A finite element based model predictive controller (FEMPC) is implemented for attenuating vibrations of a two flexible link planar manipulator. This manipulator consists of two revolute joints driven by DC motors. Due to the flexibility of the links, both links are susceptible to vibrations, hence, reducing the accuracy in tracking of the end effector. As such piezoelectric plates are use as actuators to apply corrective action to suppress vibrations. The FEMPC control structure, determining these actions, is based on the structure used in dynamic matrix control (DMC), with the exception that a finite element (FE) model replaces how the predictions are formulated. This FE model is developed from and utilized to described the dynamics of each individual link. The FE predictor uses the measured strain and control actions sent to the setup to simulate the response of each link. Results show that using model predictive control has advantages in vibration control over simple conventional control, in particular proportional control. Furthermore, improvements on the model used in predicting the vibrational response will further improve on the attenuation of vibrations.