Research On Shock Response Characteristics Of One-stage Light Gas Gun Position Adjustment Mechanism

The problem of rigid strength of attitude adjustment mechanism during gas gun firing is a key research direction in achieving multi-degree-of-freedom adjustment and high targeting accuracy in gas gun firing system.Today,with the rapid development of mechanical theory and computer technology,there are new technical ways to study the design and impact response of gas gun adjustment mechanism under impact load.The traditional horizontal and rail type gas gun firing system is difficult to conduct firing tests for complex conditions such as multiple firing angles,strong impact,and high aiming accuracy,so it is important to conduct research on the impact response characteristics of the gas gun posture adjustment mechanism.In this paper,the structural dynamic strength design and research are conducted for the50 mm caliber gas gun attitude adjustment mechanism,and the structural dynamics analysis and impact response characteristics analysis are carried out for the overall layout and parameters of the initially determined gas gun attitude adjustment mechanism by applying nonlinear finite element and numerical calculation theories.The impact response characteristics of the gas gun attitude adjustment mechanism were studied under different parameters.The overall model of the gas gun attitude adjustment mechanism is established,the composition and working principle of the attitude adjustment mechanism are introduced,the rigidity and strength of the key components of the attitude adjustment mechanism are analyzed by the finite element method,and the weak points in the structure are identified.The design of the bracket platform is improved,and the stiffness of the bracket platform is effectively improved.For the problem of poor stiffness of the adjustment mechanism trunnion,a solution was proposed to change the waist-shaped hole structure to dovetail slot structure,and a reasonable layout of the trunnion was made on the basis of its thickening and reinforcement.A nonlinear finite element dynamics model of the gas gun firing process posture adjustment mechanism was established,a finite element modal analysis of the gas gun and a simulation of the gas gun firing process were conducted,and the impact response characteristics of the gas gun posture adjustment mechanism were studied in terms of stress and deformation of the frame structure.A one-stage gas gun firing test platform was built,and the impact response analysis of the key parts of the posture adjustment mechanism was carried out based on the strain characteristics,acceleration and displacement characteristics,respectively,to obtain the time-frequency information of the posture adjustment mechanism of the gas gun under different firing parameters.The correctness of the established nonlinear finite element dynamics model of the gas gun and the reliability of the constructed internal ballistic model were verified by comparing the finite element calculation results with the experimental test results.The results of the impact response simulation analysis using the time domain waveform of the gas gun impact basically match with the time domain waveform of the gas gun firing test results,which demonstrates the feasibility of the method.