Studies On Omnidirectional Three Dimensional Measurement And Stereo Model Development Techniques

On the basis of complete analysis of the hot topics and tendency on 3-D measurement field, the theory of optical 3-D measuring is discussed systematically and techniques related to omnidirectional measurement and model development are studied well in this dissertation.FTP and PSP as popular demodulation methods based on raster projection measuring methods are studied respectively in frequency domain and space domain, such that PSP are made to be measuring method mainly due to its anti-noise performance through analyzing their advantages and disadvantages. Phase shift step is then discussed and be chosen properly concerning implement possibility. After considering errors introduced by phase-shifter and non-linear property of image detector, an effective method is proposed to improve measure precision.Due to light circuitry structure limit, raster fringe deformation with its space frequency influences accuracy. A new method used to create reference grating image automatically when demodulating is proposed and through experiment it is testified that it can meet measuring requirementnd effectively.Considering the object blind area when collecting 3-D information, multi-view collecting strategy is introduced to get modulated 2-D grating image. Adopting Screw theory, point clouds registration based on constrains of marked points is demonstrated to be effective and performed well.Triangulation algorithm in 3-D domain is applied to rebuild object shape and the stereo rebuilt model is realized to be visualized. Furthermore, to facilitate data exchange with popular CAD software to further design or develop, the structure of IGES is studied and applied.In all, the achievement of the studies effectively promotes the development of 3-D measurement techniques.