Research On The Techniques Of Portable Variable Scale Laser Measurement And System Development

3D profile measuring has been applied more and more widely in areas such as aerospace, biomedical engineering, precision instruments. Portable Variable Scale Laser Measurement Technique has been fully researched in this thesis. The key techniques including image process, calibration, binocular stereo measurement, matching, merging, etc. we also developed handheld variable scale three-dimensional laser scanner. The thesis’ s main contributions are as follows.(1) Hand-held 3D laser scanning technology has been researched, a scanning algorithm combined monocular vision and binocular vision is proposed. The program can move freely during the scan, examples show that we can scan complex contour of the target objects efficiently.(2) A cross laser stripe center extraction algorithm by combine cross laser stripe adaptive extraction and cross laser line automatic segment is proposed in this paper for real-time 3D laser scanning. The algorithm in this paper has been applied into a handy laser scanner, which increased scanning efficiency with high practicality.(3) A binocular stereo matching algorithm based on marked point is proposed in this paper. In this algorithm, it is demonstrated by experiments that our matching algorithm is robust and effective.(4) This paper proposes a robust matching algorithm based on spatial marked points which can significantly avoid the ambiguity problem in the process of stitching. According to the experiment results, it only takes less than 2ms to reach the accuracy of 100% when matching the marked-points in two views.(5) A variable scanning technology is proposed in this paper after analyzing the 3D scanning technology for big object which can effectively reduce the measuring error of the large target object.All the algorithms have been fully analyzed in this paper, we have developed hardware platform of hand-held 3D laser scanning system.we also designed system software architecture according to various functional modules.at last,we program each algorithm module including system calibration, stereo matching, 3D merging, cross laser stripe reconstruction, etc.