Research On Key Technology Of Fragment Velocity Measurement System In Harsh Environment

Fragmentation anti-personnel warhead is formed by a large number of high-speed fragments under the action of high explosive,which can damage targets by high-speed impact,ignition and detonation.When the shape and mass of the prefabricated fragment are fixed,the kinetic energy depends on the velocity.Therefore,fragment velocity is of great significance to study the damage ability of ammunition and is an extremely key evaluation index of the damage effectiveness of ammunition.However,the fragmentation warhead explosion produces strong transient impact and strong electromagnetic radiation interference,which puts forward higher requirements on the anti-jamming performance of the fragmentation velocimeter.How to accurately measure fragment velocity in harsh environment becomes a big difficulty.In view of the above problems,research is carried out from the following aspects:Firstly,this paper studies and improves the chip speed test system based on comb target which can be monitored remotely and wirelessly,introduces the system composition,designs the impact resistance power supply,photoelectric isolation fiber trigger circuit and data acquisition circuit,writes the corresponding firmware program,and uses Modelsim to complete the FPGA timing simulation.Lab VIEW is used to design the upper computer for data processing.Secondly,a one-dimensional explosive model was established to solve the variation of detonation field,and then the overall performance of the device was simulated in different environments.The shielding shell is added to reduce the influence of electromagnetic radiation,and the steady-state circuit is used to solve the problem of power supply instability when the device is subjected to strong impact pressure,which improves the stability of the device.Finally,numerical simulation and theoretical calculation are carried out by USING LS-DYNA to study the flying characteristics of prefabricated fragments in the air under the action of high explosive.Based on the simulation results,the velocity curve of the prefabricated fragment at each time is drawn,and the Angle of scattering direction is calculated,which provides a certain reference for the research and development and design of the fragment velocity measuring device.