Abstract
Active control methods are used to suppress vibrations in a pneumatic isolation table. To suppress vibration for large displacements, it is necessary to switch the control input instantaneously to the maximum or minimum input values. Therefore, active control by quantized control input generated using the on-off valves is suitable. To obtain high performance, it is necessary to consider the quantized action by on-off valves and the input time-delay that arises from loss of pressure. An important factor is that the quantizer used in this system is a non-linear quantizer. Although conventional methods can be applied to the system including the non-linear quantizer, it is highly possible that a performance of disturbance attenuation deteriorates compared to when using a linear quantizer. Therefore, a control method that can be applied to the system including the non-linear quantizer and can give high performance is proposed in this study. Furthermore, the proposed method is applied to a pneumatic isolation table and its performance is verified through numerical simulations and experiments.
