Flier Speed Test Key Technologies Research

The instantaneous muzzle velocity of the projectile, an important tactical and technical parameter to evaluate or test its overall system performance, can be used to assess the impact energy to the target and predict its lethality. Becurse of its simple structure, easy operation and high precision measurement, the velocity measurement system of light screen target is becoming the main method to measure muzzle velocity of projectile today.After studing many documents on the methods for evaluating the projectile velocity home and abroad, a totally new laser velocity measuring system was designed. It could be used to mesure the projectile velocity of varous bullet of materials and meet the reqirements of muzzle velocity measurement of almost all kinds of firearms with different calibers now. The idetification method to determine the accurate moments for the bullet to just pass the two light screen targets was studied.The main contrubutions of the paper are:(1) Based on the analyses of the optical devices and optical systems, a optical path that could expand the point light source into a line of optical path was designed, thus an even parallel and uniform light screen was obtained.(2) With comparison circuitry, the irregular signal was changed into pulse signal through photoelectric conversion circuit, high response PIN photodiode array as detector elements, preamplifier and main amplifier for conditioning and amplifying original signal.(3) The new methods for extracting the time of projectile passing the target,such as the trigger methods of the bullet top and the bullet end, correlation detection, wavelet analysis and so on were put forward. These methods were made into comparison and analysis by experiments, and the results demonstrated the correctness and validty of the proposed methods.(4) Single Chip Microcomputer, the core component, was used to design the related circuit and program that was used for measuring system processing. Together with the use of CVI for panel design, the PC programs were written.(5) An error analysis of the volocity measurement system was conducted, and the precision of timing circuit through experiments was inspected. The test results demonstrated that the designed timing curcuit had excellent accuracy.The completed work and reseach results have great meanings for the further stuies of muzzle velocity laser mesuring system, and also for the measuring accuracy enhancement of other kinds of velocimeters.