Luminosity Analyzing Technology On Measuring Velocity Of Light Tracer

The velocity measurement system of tracer bullet is mainly used in measuring the flying velocity of tracer bullet.The screens of the velocity measurement system are composed of the luminosity analyzing target and conventional velocity measurement light screen targets.The luminosity analyzing target is easy to fail in testing tracer bullet's light intensity when the tail trailing light fluctuate enormously.The conventional velocity measurement light screen targets cover a narrow range of bullet caliber in test,and it is inconvenient for Manual adjustment of gain.Aiming at the problem of insufficient dynamic range of circuit test in the velocity measurement system of tracer bullet,Log Amplifier is used to design a signal-processing circuit of the luminosity analyzing target to broaden circuital testing dynamic range,and a gain adjusting circuit of normal target by digital potentiometer is designed.Main research contents of this thesis are as follows:Firstly,by summarizing the methods of measuring bullet's velocity and the development situation of velocity measurement technology of tracer bullet,and analyzing the distribution characteristics of screen detection receiving field of view,the conclusion about shortcomings of the existing tracer bullet velocity measurement system is made,on the basis of the analysis which includes the tracer bullet structure,luminous theory and the waveform analysis of the target signal in firing practice test.The overall scheme of improving the dynamic range of the test is put forward.Secondly,based on reliability theory and specification,design of both voltage type and current type signal-processing circuit for the luminosity analyzing target which have logarithmic amplification function,and the gain adjusting circuit for conventional target are made.The paper selects a circuit designing scheme,draws schematic circuit diagram and PCB diagram in Altium Designer,manufactures the real object,and conducts the test on that.Then,a test platform for the luminosity analyzing target in velocity measurement system of tracer bullet is designed and built.The Logarithmic output characteristic and time measurement effect of the luminosity analyzing target are verified by the test platform.The velocity measure error of the logarithmic transformation is analyzed and verified by simulation in MATLAB.After that,the failure mechanism of electronic components is analyzed.The reliability analysis of the signal processing circuit for the luminosity analyzing target is carried out,including the establishment of the reliability model,the raise,distribution and testing of the reliability index,and the reliability prediction and optimization of the circuit.Finally,the designed tracer bullet velocity measurement circuit is tested and verified indoors,and the firing practice comparison test is conducted at the shooting range.The results show that the designed circuit is applied in the existing tracer bullet velocity measurement system,the work is stable,and the dynamic range is extended from 15dB to 60dB.