| The portable vision 3D coordinate measuring system based on photogrammetry technology presents many characteristics such as light and portable device, fast and flexible construction, simple operation, large measuring range, high accuracy, capable of measuring on spot and not affected by the difference of measured surface. So the system has wide prospective applications in many fields. After a comprehensive review on the indoors and overseas current situation and developing tendency of portable 3D coordinate vision measurement system, a dual cameras vision 3D coordinate measuring system using a probe has been proposed to solve the problem of the measuring instability about similar system with one camera. In the dissertation, mathematic models are built up and solved about this kind of system. The experimental result shows that the system with linear points and dual camera has achieved a measuring stability precision of 0.2mm and measuring precision of±0.15mm in the direction of every axis for a distance of 1500mm away from dual camera.The dissertation covers the following aspects concerning the main work and creative research in the project.1. The composing of a probe vision coordinate measurement system has been discussed. The material selection principle and feature requires of system's parts have been proposed on the basis of system's characteristics, and the sample system in the laboratory has been composed.2. Based on the principle of Perspective-n-Point Problem (PnP), the system's mathematic model about the position between n points and one camera has been proposed and established. A system consisting of probe and camera is proposed as line,plane and space system which supply the mathematic basic for similar one. Dual camera with perpendicularity of two axis system is proposed to compensate the instability of one camera system with probe.3. The CCD camera calibration model has been analyzed and established. As for two plane array vision sensors, a high accurate dual cameras'inner and outer parameters calibration method based on CMM has been proposed with a large range moving drone. Using that method, the two cameras'inner and outer parameters in the system can be attained.4. The extraction method for the measured object point's image center has been studied. The two-stage method is used to position and distill the circular measured object point's image center, and the experiment result shows that that method is fast and accurate. A drone with spherical object points has been designed, and the circular object point extracting method based on circularity error evaluation is presented to position the circular object points. 5. The experiment has been conducted to test the system's total measuring precision. Several comparative experiments with the single camera-probe system and CMM are also included. The experiment result shows that the dual camera-probe system is of higher accuracy. The system with three linear points and dual cameras has achieved a measuring stability precision of 0.2mm and measuring precision of±0.15mm in the direction of every axis for a distance 1500mm away from dual cameras.Through theoretical analysis, experiments and computer simulation, 3D coordinates vision measurement system with probe & camera have been studied with emphasis on the system's composing and measuring principle, the system whole mathematic model and its solution, system image process, objective recognition and position detection, design of objective, camera calibration for single camera and dual camera. In the dissertation, some creative progresses are made and some new methods and conceptions are proposed. The work lays a foundation for further development of the practical portable vision 3D coordinate measuring system with higher measuring stability.
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