Development of Position Control for a Single-Axis Active Pneumatic Isolation System via High Speed on/off Valves

Position control of the single-axis active pneumatic isolation system is realized on this research. Innovating parallel dual-on/off valves with PWM control signal is implemented to control pneumatic isolation system for positioning and trajectory tracking control and then the pneumatic high speed on/off valves have the advantages of low cost. In this study, we use software to realize PWM technique to control on/off valves’ open and close time. Therefore, we do not have the hardware circuit to implement pulse width modulation and not only cost down but also reach control precision of demand. Intermittence fluid is formed by changing of high speed on/off valves and performance of average fluid is obtained by adjusting duty cycle, so as to achieve the effect of gas flow control, and to achieve all digital signal of the control system.n the first place, the non-linear mathematical model of vibration isolation platform is founded. The dynamic system is simulated by MATLAB. After open-loop model is completed, we combine this model with Fourier series-based Adaptive Sliding Mode Control with H infinity tracking performance to design controller to form a close-loop control. In this study, the pneumatic isolation platform is controlled by parallel dual-on/off valves to achieve active control. When the pneumatic isolation system is achieving steady-state and the allowable error is smaller than the demand, air source is shut by parallel dual-on/off valves. The continuous high change is prevented by using a single on/off valve after steady-state.