Research On Control Algorithm And Experimentation Of Pneumatic Servo System

With the development of mechanization and automatization, pneumatic technology is applied widely in industry more and more base on a series of obvious advantages. But the control performance of the pneumatic system is not very good because of its inherent non-linearity and low-stiffness. With the development and perfection of modern control theory and intelligent Control Theory, and the appearance of electro-pneumatic proportional valves with higher capability, it is possible to achieve higher precision and responsible control in pneumatic system. The pneumatic position servo system is studied by self-tuning adaptive control theory in this dissertation.In pneumatic system, the parameters and variables in both the chambers are nonlinear when the gas actuator is working, so it is difficult to achieve the precise mathematical modeling of the pneumatic system, and that is the reason why couldn't control the pneumatic system accurately with the traditional control theory. The approximate mathematical modeling is founded, and the qualitative analysis to the primary parameters which affect the control performance are achieved in this dissertation. Base on this, the discrete mathematical modeling of the pneumatic system is founded, and the pole-allocation self-tuning adaptive controller is designed, then parameters and output values is estimated by on-line identification. The experimental results demonstrate the excellence of this control strategy.The friction of cylinder and other disturbance factor make great effect to the control performance of the pneumatic system, so the discrete mathematical modeling of the pneumatic system should accurately reflect the friction of cylinder and other disturbance factor. In this dissertation, the degree of the noise polynomial in the discrete mathematical modeling is increased, then the identification arithmetic could accurately estimate the effect of the friction of cylinder and other disturbance factor, so the precision of identification and position control of the pneumatic system is improved. The experimental results demonstrate the exaction of this technique.In system identification, the performance of identification arithmetic influence the accuracy of the discrete mathematical modeling directly, consequently, which influence the accuracy of the control system. In this dissertation, on-line identification aimed at pneumatic position servo system using Recursive Forgetting Factor Method (RFF) and Amendatory Square-root Method, the experimentation demonstrate that the...