Study Of Flat Flexible Platform Based On Pneumatic Proportional Control System

Since pneumatic system has many advantages,such as no air pollution, low cost, simple consturction and easy to operator, it has been widely used in the industry field. Now,with emergence of the electric-pneumatic-servo control technology, pneumatic system was extended from logic control to servo control. However,the inherent characteristics of the pneumatic system,such as the condensability of the air,nonlinear of valve and friction characteristic of pneumatic cylinder, greatly increase control difficulty in a degree,and hard to satisfy the orientation request in industry.Based on the characteristics of pneumatic sevro system with proportional valve and a single-rod double-acting common pneumatic cyclinder,a flat flexible platform which can do flexible controlling is bulided by researching and simulation analysis of the control strategy.Firstly,a nonlinear mathematic model is bulit and simplified on the base of careful analysis of characters and principle of the system.The reaserch the control system of the pneumatic proportional control system. Incremental PID control and Self-adaptive Fuzzy-PID control are put forward.For Fuzzy-PID,its PID parameters,such as Kp,Ki and Kd make the dynamic change so as to keep the optimal state at every moment in order to obtain the approving control effect.Secondly, the simulation of the control systems was done by using the MATLAB/SIMLJLINK tool,and the results were analyzed and compared. Compared with the result of the tradition PID control system, the Fuzzy-PID control system's result shows that there is no slipping oscillation of step response,the squarewave response is stable, the precision of sine wave response in a certain frequency band is improved and its adaptive ability is enhanced. At the same time, by using the mixed programming in Lab VIEW and MATLAB, the flat flexible platform which is used to do the real-time control was builded.Finally, the work of this study is summarized. For the shortages and disadvantages still existing in the study, some suggestions and expectations are put forward for further research.