Study On The Optical Precision Detection Method Of 3D Morphology Based On The Structure Light

With the rapid development of manufacturing industry in the whole world,it is well known that size and 3D-dimension of objects,as an important indicator,has become the main test program in modern production quality control.However,precise detection for the outline of curved object and the thickness of transparent objects exists plenty of challenges,so that how to obtain samples of high precision nondestructive and on-line profile information has still being a difficult and hot research at home and abroad.Recently,with the advantages of non-contact,high precision,automation,structured light measurement technology get rapid development and has been widely applied in industry,agriculture,biology,medicine and other fields,3D reconstruction and object recognition have especially become the hot issues.The fundamental of structure light measurement method is that the light projector put controlled point、band、flat upon the tested object,and the image sensor(CCD)receive image.Finally,we will transform the 2D image information into 3D coordinate object by using mathematical modeling of system geometry.This paper focus on the thickness panel glass and aerodynamic components of contour detection problem,researching on lined structured light and grating fringe projection,while deeply discuss different types of structured light and key problems in industrial detection.In the lined structure light of measurement for the thickness panel glass,a nondestructive and on-line measurement system was proposed,which can be used in industrial measurement.The maximum detection thickness was 23mm and the precision of the nondestructive and on-line measurement system can reach 4μm.As a result,by measuring the thickness of glass printing ink,this instrument can complete a high-precision,fast and nondestructive detection,which offers a broad application prospect.In the aspect of 3D contour reconstruction based on grating fringe projection,this paper made use of digital projector(DLP)to realize the automatic precision detection of the streamline components as the application target,and systematically constructs the digital 3D reconstruction measurement system.And the precision of the test is better than 3.5mm.This technique has promoted the development of reverse engineering technology in our country,which has a far-reaching impact.Combining theoretical analysis and experimental research,this paper carries on the concrete practice to study the thickness of panel glass based on machine vision and the key technology of curved surface,and gave a careful analysis of the error in the measurement.