A synchronous mutual position control for vertical pneumatic servo system

Synchronous control Of Mutual position for two vertical-type pneumatic servo systems is discussed for practical use in this study. In the proposed control system, a fuzzy controller is used in each pneumatic servo system so that the output of each plant can follow the reference input. A PD controller is introduced to realize the synchronization of both pneumatic servo systems, in which the outputs from this controller are the inputs for revision to both plants. A fuzzy virtual reference generator that can adjust the reference input to both fuzzy controllers adaptively by fuzzy rules is constructed to improve the transient performances of both axes. In addition, the adjustment controller produces a representative value of both cylinder outputs, which is used to synthesize the inputs to the fuzzy virtual reference generator, in order to reach a compromise between the follow-up ability to the reference input in each axis and synchronization of both axes. The applicability of the proposed method is confirmed by experiments using two existent vertical-type pneumatic servo systems.