Design Of Field Velocity Measuring Device For Static Bursting Disc

The test of fragmentation velocity in static detonation field is an important step to evaluate the combat damage effectiveness of warhead.Traditional test devices mostly use contact target timing or high-speed data acquisition waveform analysis,which has problems such as cumbersome arrangement,large workload,poor reliability,low efficiency of repeated experiments,and easy to trigger by mistake during on-site testing.According to the requirement of testing in the harsh environment of static detonation field,a fragmentation velocity measuring device with non-contact laser testing and off-line data storage functions is designed.The fragment group generated by static detonation field is characterized by a large number of fragments per unit area,discrete fragment size,and time sequence differences,etc.Aiming at the problem that the traditional test method can only complete the first fragment velocity record but cannot obtain multiple fragment velocity parameters,this paper proposes a design idea based on the principle of zone intercept velocity measurement,which takes the two-optical path one-line laser curtain and array PIN detector as the core.The laser transceiver integrated optical path is designed based on the original reflection screen,which greatly simplifies the optical path volume and improves the field survival ability of optical equipment in harsh environment.The fan-shaped light curtain formed by laser has large effective area and high central position,which can effectively improve the capturing ability of warhead fragments.In this paper,FPGA is used as the main control chip,design signal collection circuit around high-speed AD acquisition chip AD9238.The sampling rate can reach 20 MHz,and the target signal can be collected completely.In order to solve the problem that field test requires multiple experiments,FIFO data cache and NAND Flash chip are used to complete high-speed data acquisition and storage,which can store multiple groups of experimental data.The data transmission mode of USB bus is designed,and the ability of testing fragmentation cluster speed and multigroup fragmentation data transmission is realized.After the completion of the test,the fragment cross target waveform is obtained by using the data processing algorithm of waveform correlation and peak extraction on the Lab VIEW development platform.The function of the system is verified by the projectile velocity measurement experiment.A stroboscopic source irradiation experiment is designed to verify that the device can measure the velocity of fragments at 3000m/s.According to the theoretical error calculation and analysis,the velocity measurement error of the device with a target distance of 0.3m is 2‰,which meets the test requirements and verifies the feasibility of the device.