Reduction of residual vibration in a rotating flexible beam

The reduction of residual vibrations of the position control of a rotating flexible beam is investigated. The control scheme is achieved by combining Input Shaping Technique (IST) with a piezoceramic actuator (PZT) attached to the surface of the beam. IST reduces residual vibration in the beam by convolving the desired torque with a sequence of impulses. A majority of the current IST is inherently open-loop where impulse application at an inaccurate instance can lead to system performance degradation. Thus, in order to improve the control performance of a flexible manipulator, the residual vibration generated due to those or the uncertainty model was further suppressed by the PZT. The optimal control voltage was determined by the Linear Quadratic Regulator (LQR) technique. The dynamic simulation shows that the proposed method has not only nice robustness properties for suppressing the vibration due to an inaccurate model or the instance of impulse application, but also the voltage applied on the PZT decreases 50% or more than only using PZT, in other words, the extra energy consumption is reduced significantly by the proposed method.