nodal point method

Compensation of Distortions of Images of Traces on the Deformed Bullets for their Automated Comparison

Introduction. The purpose of work is: a research of ability of compensation of distortions caused by deformation of bullets. Theoretical analysis. In work examined bullets with deformation in the type of local annular expansion. This type of deformation is basis for compensation of complex distortions. Nodal point method selected for the evaluation of image distortion and compensation. Model experiment. Model of deformed 9 mm bullet obtained in 1:50 scale for determination of transformation coefficients. The table of transformation coefficients obtained by means of experiments for different diameter variations. Experimental studies. Experiments have been carried out for bullets, the shot from a Makarov pistol caliber 9 mm. The overlapping of images of non-deformed and deformed bullet showed before converting divergence of paired attributes in brinks images. Distortions of trace images on the deformed bullet compensated. Coinciding traces overlapped almost completely. Conclusions. The algorithm compensation of distortions of deformed bullets images develop. This system approved for symmetric deformation. The algorithm can be used for compensation of distortions of traces images on the deformed bullets.