Dynamic And Static Analysis Based On Multichannel Fringe Projection Test Method

Non-contact measurement is an important part of optical measurement and practical measurement.Considering the fact that the object under test is far away from the measurer,or the object is soft and easy to be deformed,we have to use non-contact measurement to get the relevant information of the object.Phase Shift Profilometry(PSP)is an important part of non-contact measurement.This method uses the phase change caused by the distortion of different phase fringes to obtain the contour information of the object surface.It has the advantages of high precision,good antinoise performance and easy calculation.In this paper,the multichannel characteristic of color image is used to input the phase shift fringes into different channels.By solving the problem of color crosstalk,the fringe projection test method of multichannel color is realized by combining the PSP.And it is applied to the dynamic and static analysis of adaptive lighting and measuring micro-vibration data.In multiple reflection scene,high reflectivity object part will appear pixel saturation phenomenon,low reflectivity image will appear dim phenomenon in a part,it will cause the loss of image detail,and it’s difficult to do the measurement and calculation,before that,the research of adaptive illumination is done in mono image,to achieve the result dozens of iterations are needed,the iterative algorithm converges slowly,using algorithm computational complexity,in industrial measurement,the requirement for real-time is very high.Therefore,it is necessary to propose an adaptive illumination method with fast iteration speed and simple algorithm.Micro vibration can be seen everywhere in our daily life,such as bridges quality inspection,earthquake monitoring,etc.But the parameters of the micro vibration is difficult to get,which is usually in millimeter and submillimeter level,some vibration measuring devices don’t get this level of vibration signals,making it difficult to measure.In this article,we provide a well-performed micro vibration measurement method to which the multi-channel fringe projection is applied.The main contents of this paper are: Based on the construction of the projectioncamera optical system,by solving the problems of color crosstalk and other problems,the phase shift method is completed by using the color image,and the method is applied to the practical static analysis.For static analysis,the adaptive illumination process is accomplished by using multichannel fringe projection test method,which can achieve the desired effect in both strong and weak light,and the details of the image can be seen.And two kinds of non-reference visual quality evaluation methods are used to evaluate the image,and the iterative stopping conditions under the contrast evaluation method are given.For dynamic analysis,the multichannel fringe projection method is used to measure the micro vibration parameters,and the measurement speed and accuracy are greatly improved by using the projection of a single color fringe image in the measurement.By using this method,we can get 0.1 Hz to 2 Hz micro vibration waveform,minimum vibration amplitude is 163 microns,which meets the needs of most real-time measurement of industry.Furthermore,the whole process of dynamic and static analysis,using low cost commercial camera and projector,is easier to put into use widely.