The Techniques Research Of The Foot3D Reconstruction

Because the society has a rapid development rhythm, people ignore the maintenance ofthe foot, in order to satisfy the needs of people’s foot correction and designing thepersonalized shoe’s model,it needs to get the foot3d parameters, such as the arch, the footlong, the height of the left and right ankle, the outline of foot, etc., so doing the techniquesresearch of the foot3d reconstruction has an important significance both in making the propershoes according the size of the foot and the correction of clubfoot in the medicine. Designingthe simple and efficient foot measurement systemswith taking advantage of the photoelectrictechnology and computer technology which are rapid developmentis one of the mainimportant research topics to scholars.This paper develops the key techniques research of the foot3d reconstruction with usingphotoelectric technology and computer technology, which combined with the principle ofbinocular stereo vision. And does in-depth study of the key techniques of the foot3dreconstruction includingthe binocular camera’s calibration, the foot image acquisition,calculating the real phase, the splicing of foot clouds combined the foot measurement system.The paper has the innovation and improvement of the current foot three-dimensionalreconstruction techniques to put forward the simple and efficient video camera calibrationmethod based on the video and the error correction coding point’s algorithm which is appliedin the footclouds splicing,this paper does the work as follows with the purpose of improvingthe precision and speed of the foot3d reconstruction:1. Because the simple practicality of binocular stereo vision and the grating projectionapplication in the process of the foot3d reconstruction, thusthe basic knowledge of camerasand projectors and related principleshas been learned to choose two high-performance videocameras and high-precision projectors, eventually a foot measurement systembased on the binocular stereo vision has come into being.2. After producingthe black and white camera calibration template with high precision,the camera calibration method based on the video has been put forward, this method does theresearch based on the Zhang Zhengyou camera calibration method. The improved cameracalibration method applies the template matching algorithm, using VC6.0programmingimplements the improved calibration to get the binocular camera’s internal and externalparameters, the camera calibration method based on the video is simple and feasible, whichcan implement the calibration of binocular camera with low cost and high precision.3. The foot measurement system using the projector with the high performance projectsinusoidal grating stripe on the foot model, projection grating stripes can generatedeformation when meeting the foot, this article calculate the continuous phase for thedistortion fringe images with applying the related method, and then restores thethree-dimensional model of foot. It involves the phase unwrapping in the process, this articleadopts the four-step phase shift method to get the wrapping phase, and applying phaseunwrapping method with moire fringe obtains the real phase of the distortion fringe images.The phase unwrapping method of moire fringe project the two sinusoidal fringe withappropriate frequency on the foot model, the two stripes addition (or subtract) can form themoire fringe,which making the whole foot within the field of moire fringe at level1, and thenapplying a simple formulacomputes the real phase of the deformationstripe images.4. When the grating projection projects the strips on the foot,the binocular cameraobtains the deformation strip images, respectively gets the real phase of the images whichhavebeen taken by the binocular camera using the method of step3introduces, using the methodof equal phase in the two images whichhave been taken by the binocular camera for thespace’s same point to find the corresponding matching point, and then according to thecalibration parameters of the cameras and all of the matching points on the images regainthe three-dimensional topography of the foot, it greatly improves the matchingprecision ofthe corresponding points by using the binocular stereo vision system.5. Based on the existing point cloud splicing methods with feature point,the in-depth study goes on, then the error correction coding algorithm has been design, and the existingfoot point clouds splicing methods have beenintroduced.The error correction coding algorithmhas been validated by the related experimentin this paper, based on the error correctionprinciple of hamming code, the error correction algorithm can accurately correct an error ofthe marking points, the algorithm can make the process of the point clouds splicing based onthe encoding marking points more accurate with the errorcorrection ability of the algorithm.6. Finally, the experiments and validations have been done about the key techniques ofthe foot3dreconstruction including the camera calibration, the foot images acquisition, thephase unwrapping, the corresponding points match of the binocular camera’s images,the foot3d contour acquisition and the error correction codingalgorithm using the foot measurementsystem.