By-pass valve control to improve energy-efficiency of pneumatic drive system

In order to improve the performance and energy efficiency of the pneumatic drive, the by-pass valve control scheme is designed and studied. For pneumatic positioning application, in the constant speed phase, the inlet and outlet chambers will be connected via by-pass valve to reduce the overshoot and allow some exhaust compressed air to be reused. Therefore, compared with the traditional control of the motion of the asymmetric cylinder, a 12–28% saving in energy use can be acquired and meanwhile the position accuracy is maintained. Preliminary results from the simulation and experiment studies will be reported