Key Issues A Pneumatic Transmission System

The pneumatic weapons have great advantages of simple structure of ammunition and easily controlled launching energy compared with the traditional gunpowder weapons, and particularly suit to the occasions which have the requirements of changeable launching energy. So they have broad application prospects in the areas of counterterrorism.In this paper, the working principle of a kind of compressed air driving weapon was proposed; the overall structure of the pneumatic weapon was designed; the working process of pneumatic launching was divided into the pressure control process and the launching dynamics process; the fundamental theories of the pneumatic launching were studied.Based on the theories of thermodynamics and one-dimensional quasi-steady gas dynamics, the mathematical model of the pressure control process with the PID control strategy was established, and the numerical simulation solutions were calculated by MATLAB/Simulink. Finally the dynamic response change of the outlet pressure of the pressure control process was obtained.Based on the theories of Hertz contact, thermodynamics and one-dimensional quasi-steady gas dynamics, the model of friction force of the projectile and the variable mass thermodynamics model of inner barrel gas were established, and the dynamics model of the launching process was established thereby. The numerical solutions of the state parameters of inner gur-barrel gas and the motion parameters of the projectile were obtained. Based on the above work, the effects on the launching process caused by the changes of compressed air pressure and the structure parameters were analyzed. The whole mathematical model of launching process coupled with pressure control process was established, then the numerical simulation was calculated, and finally the change of the inner barrel gas pressure and motion of the projectile were obtained.The results in this paper have great theoretical significances to guide the research and design work of the compressed air driving weapon.