Research On Triggering Technology Of Exterior Ballistic Test

In the external ballistic test of the weapon system,the muzzle trigger device can be used directly as the external trigger signal source of the test instrument to control the test instruments.This method not only has high reliability,but also has simple structure and strong reusability.The muzzle trigger device relies on the muzzle flame to generate the trigger signal,but the trigger time is not consistent with the moment when the projectile is out of the muzzle,therefore,when the weapon system is required to accurately test the external ballistic flight time and distance of the projectile,it is necessary to correct the trigger time.Firstly,the paper analyzes the causes of triggering time deviation of fixed threshold trigger mode,on this basis,two kinds of trigger time correction schemes are proposed,the trigger time correction is based on the statistical principle and the trigger time correction of the backward push method is based on the projectile velocity,and the principle of two kinds of correction schemes is described in detail.Secondly,in order to obtain the waveform signal of the muzzle flash more directly,the radiation characteristic of the firelight signal is analyzed and the suitable infrared detector is chose.To satisfy the research,the detection and acquisition circuits of muzzle flash based on FPGA are designed.Thirdly,in order to obtain more reliable experimental data and reduce the interference of the noise in the signal,research and improvement of the de-noising algorithm for the muzzle flash signal is carried out,the de-noising effect has been improved.In order to achieve the correction algorithm based on statistical principle better,different methods are applied to extract the characteristic points that cannot be directly observed in the muzzle flame signal,wavelet transform is used to detect and extract the singular points in the signal.According to the characteristics of muzzle fire signal,the slope method is used to detect and extract the maximum slope point in the signal.Finally,the two time correction schemes are tested under different detection conditions,and the experimental data are analyzed.The experimental results show that the fire detection system has good function,and the de-noised signal can provide reliable data support for the algorithm.Through the analysis and comparison of experimental data,the statistical principle correction method is correct and feasible with the singularity point of firelight signal.It is able to rectify the time deviations that are generated by the trigger.For the time reversal method based on the projectile velocity,the error analysis and simulation are carried out to prove its feasibility,and finally verified by experiments.