Research On Measurement Method Of Fragment Position Base On Line Laser And Array CCD

In the field of weapon range testing,the position information of the fragment in the process of dispersion is not only an important indicator to measure the performance of the fragment warhead,but also a key parameter to assess the target destruction effectiveness.Due to the uncertainty and randomness of the fragment scattering,this brings great difficulties to the measurement of the fragment position;especially the phenomenon of multiple fragments flush to the detection plane appearing blocking and overlapping,which aggravates the difficulty in identifying the fragment position information and makes it difficult for the existing test method to meet the demand of the fragment position measurement.Therefore,Therefore,this thesis carries out research work on the fragmentation position test method to provide measurement basis for the fragmentation position information in the specified area.In order to effectively solve the problem that it is difficult to measure the fragment position after the explosion of fragment warhead,this thesis proposes a fragment position testing method based on line laser and array CCD.According to the spatial structure relationship between laser detection light curtain and array CCD,this thesis combined with the principle of fragmentation positioning recognition,established the fragmentation position calculation model,gave the source of fragmentation position measurement error,constructed the fragmentation position error model through error transfer theory,and simulated and analyzed the error distribution of fragmentation position on the effective detection target surface.In order to ensure the measurement accuracy of the broken piece position,this thesis carried out the structure design,signal detection and processing circuit design and signal acquisition module design for the laser detection light screen;meanwhile,the image acquisition module is designed with the effective detection target surface,the imaging characteristics of the array CCD are analyzed,the noise sources of the fragmentation image under laser illumination are given,and the noise-removal algorithm combining bilateral filtering and pass-state filtering is used to pre-process the fragment images.The contour information of fragmentation imaging is identified by the maximum interclass variance method and the Canny edge detection algorithm.and the pixel coordinates occupied by the fragment shape centers are extracted based on the least-squares fitting method.According to the spatial structure of the laser detection light curtain,this thesis analyzes various scenarios of blocking and overlapping when the fragments arrive at the laser detection light screen together,constructs a spatio-temporal constraint model of the fragment flight trajectory,screens out the sequence of fragment combinations to be determined,extracts the feature information of the fragment combinations to be determined by combining D-S evidence theory,realizes the fusion of the feature information of the fragment combinations by using particle swarm optimization algorithm,judges the authenticity of the fragment combinations to be determined,and information on the position of all fragments reaching the target target surface is determined.According to the established fragment position analysis model and fusion recognition algorithm,an experimental platform was built,image information and encoding information of the fragment over the screen were collected,and the analysis was verified and compared with the fragment coordinate information obtained from the wooden board target through quantitative and qualitative experiments.The results show that the fragment position analysis model established in this thesis can calculate the position information of the fragment reaching the target target surface,and the measurement error meets the technical index requirements;At the same time,the fragment position fusion recognition algorithm can solve the problem of difficult identification of position information brought by fragment occlusion and overlap,which verifies the feasibility and accuracy of the fragment position testing method established in this thesis.