Control system design method of precise positioning mechanism with a damper

Our proposed actuator was applied for a spin-stand tester which evaluated high areal density magnetic recording. Since, the actuator characteristic was a second order lag element that had large amplitude at a resonance frequency. However, the peak value of the resonant frequency is very high because the mechanism uses elastic deformation. As a result, a good performance cannot be guaranteed for a perturbation induced by setting a load mass. Therefore, we have attached a damper made from VEM (visco elastic material) and a restriction board on the lever mechanism to reduce the resonant peak value. In this research, the characteristic changes induced by the damper are modeled. Further, by using the model, the influence of the damper on the transient response of the precise positioning mechanism is discussed. Moreover, a controller which improves the transient response is designed and the effectiveness of the controller is illustrated by experiments. ©2013 The Japan Society of Mechanical Engineers.