The Comparison Technology Research Of Vehicle Body Paint Based On Infrared Spectrum

With the increasing of road traffic accident, the road traffic escapes case is increasing.Traffic escapes infringed upon lawful rights and interests of the accident victim, affect socialstability and unity, destroyed the normal traffic order, and caused the great influence to thestate and the people’s life. The scene of traffic escapes often leave traces of the vehicle tire,glass pieces, debris of lamp decoration, paint and blood, fingerprint debris etc.materialevidence information. This article collected vehicle body paint IR spectrum information,analysed of spectrum information features paint material evidence, established a completebody paint spectrum query database, and studied paint spectrum matching technology. Thispaper mainly in the following aspects:(1)287samples (cars156, buses50, trucks81) of auto body paint was Collected.940paint layers’ spectra (cars554, buses484, btruck205) was Collected by the Fouriermicroscope infrared spectrometer Nicolet iN10.552spectra (cars320, buses98, truck134) ofthe paint samples surface and down layer was Collected by Fourier infrared spectrometerNicolet iZ10.(2) The auto body paint clearcoat, basecoat and surfacer spectral main features wereanalyzed. Paint of infrared spectrum characteristics wave number mainly concentrated inbetween675cm-1to2000cm-1base on analyzed the experimental instruments, experimentalconditions and the sample of the influence of the spectrum. With the same manufacturer, thesame batches, the same body color models each layer of corresponding spectrum similarity upto99.5%. With different models’ clearcoat the similar degrees are very high. The basecoat’ssimilarity is under70%in different models. In the coating of similarity is very low. Theordinary lacquer putty’re similarities between83.33%~96.91%. Water-based lacquer putty’resimilarities between70.12%~96.44%. The ordinary lacquer putty compare with water-basedlacquer putty, their similarities only41.20%.(3) It had established the car body paint information database system by the MicrosoftAccess database and the VC++platform, which applied in automobile paint material evidenceanalysis and comparison.(4) The characteristic peaks for retrieval and correlation coefficient retrieval twospectrum matching technology were study. There are good methods for the car paintspectrums database system of matching method.The unknown.vehicle paint spectrums andcorresponding models were implemented by this database system. The study was funded by the National Road Traffic Safety Science and TechnologyAction Plan Project (national science and technology support key projects) of "Road TrafficSafety Law Enforcement Technology and Wide Range of Applications"(Numbers:2009BAG13A07).