A piezoelectric servo-damper is proposed for vibration control of a cantilever beam. The device has the advantage that the device and control unit can be made small and compact. An accelerometer measures the vibration of the cantilever beam and the damper is mounted at the free end of the beam. Modeling of the system is achieved experimentally and analytically by treating the control voltage from the computer to the damper as the input and the measured displacement of the beam as the output. Using the model determined. I-control action is adopted such that the damping of the closed loop system is effectively increased, and then the on-line computer control is performed to evaluate the control system performance. The upper limit of the I-gain, which maximizes the system damping within the theory of linear systems, is found due to the saturation problem associated with the damper device. Experimental results show that the performance of the control system can be well predicted by using the established model and that the best performance of the controller is achieved by the on-off type control action corresponding to the I-control action with infinite gain in the system of interest.
