Estimating Parameters of Input Shaper in Velocity Control Loop

Input shaping is an effective feed forward control method for elastic mechanical systems which require both quick motion and high accuracy. But in the presents of disturbance, input shaper alone could not give a satisfied result. Therefore, it needs to be combined with some feedback control method to get satisfied response from set point input and disturbance. Cascade control is mostly used in industry. Input shaper could be applied to the velocity loop to get rid of heavy vibration in the loop. As parameters of input shaper depend on the estimation of parameters of system to be controlled, how to design parameters of input shaper for a PI controlled velocity loop is of main concern. Analysis of transfer function of velocity loop finds that the parameters of input shaper could be estimated by the position of zeros of the velocity loop. Simulations show that the estimated parameters for input shaper work well