Theoretical And Experimental Study Of Characteristics Of Multistage Double-acting FRP Pneumatic Cylinder

The pneumatic cylinders have been widely used in industrial automation, depended on its advantages of quick speed, simple structure and low cost. However, as the compressibility, viscosity and other characteristics of the air are different from hydraulic system, the theoretical research of pneumatic cylinder is far behind its engineering application, resulting in poor performance of the pneumatic cylinder. The static and dynamic characteristics of the mathematical modeling, theoretical and experimental researches of multistage double-acting FRP (fiber reinforced plastics) pneumatic cylinder were carried out in this paper.The static and dynamic mathematical model of multistage double-acting pneumatic cylinder commonly used in mining were set up in this thesis, combining the fluid dynamics and principle of pneumatic system, the parameters of the model were calculated and the dynamic characteristics of the multistage double-acting pneumatic cylinder were simulated and analyzed. As the friction has a direct impact on dynamic characteristic of the cylinder, the friction characteristic and stick-slip motion of the cylinder were studied, the corresponding criterion and the reasons for stick-slip were analyzed, and methods to diminish friction and eliminate stick-slip were discussed.Based on theoretical research, the cylinder experimental software and hardware system was developed based on LabVIEW. Hardware includes the modification of the developed cylinder, sensors selection and data acquisition circuit; software includes multi-channel data acquisition and processing system, the cylinder experimental system was developed by LabVIEW with using local data sampling card based on virtual instrument. The static and dynamic characteristics of the cylinder were studied experimentally by this test system, which compared with theoretical simulation results.The static and dynamic mathematical model of the multistage double-acting pneumatic cylinder was established through theoretical derivation and parameters calculation, the experimental studies were accomplished, which verified the mathematical model and theoretical research, provided a basis for enhancing the pneumatic drill work performance and achieving automation of mining equipment.