Summary: | 博士 === 中原大學 === 機械工程研究所 === 101 === Previous studies have stereo vision exact match assumed under a fixed focal length of the camera, but in recent years of development, variable focal length lens system has become very popular, and has been gradually applied to robotic vision system. However, through the use of variable focus cameras will have a serious problem of stereo vision: that is, if the focal length of the lens is not fixed or is not known exactly, places its traditional depth estimation error will increase. Combined with traditional algorithms in various AF lens focal length, aperture value and the target depth changes in the three variables, no estimation using stereo vision sensing target depth, but through the image sharpness measure aimlessly go search for possible depth of field area, and then gradually drive digital video camera focus adjustment mechanism in order to complete the action. This will result in both robotic vision system is weak on the surrounding environment sensing capability.
Therefore, this study has three main objectives: one that is developed to meet variable focus lens system more precise the modified binocular stereo vision algorithms and draw objects in order to calculate more precisely the real world coordinates; Second, by the modified binocular stereo vision algorithm is more accurate and stable development of the modified stereo vision AF algorithm on open space domain, and then find out in open space domain imaging lens focus position most clearly; three is the use of the former two research results, the modified binocular stereo vision algorithm and the modified stereo vision AF algorithm on open space domain, will be used in its stereo vision image tracking system as images servo function, autonomous mobile robots can be more accurate and faster sense the surrounding environment, avoiding obstacles, follow a moving target actions for dynamic monitoring of the environment, or to complete the assigned tasks.
The experiment proved that the results of this study has six research contributions: The first is the modified binocular stereo vision algorithms can be adapted to the variable focal length lens system, and significantly improve the traditional stereo vision algorithms inaccurate depth estimates condition . The second non-uniform spacing of discrete depth level error correction equation has increased dramatically in the similarity space visual accuracy. The third is the affine space warping error correction equation is already significantly improved formal affine space stereo vision precision, the affine space warping error correction equation is definitely the most accurate currently known binocular stereo vision algorithms. The fourth is the modified stereo vision AF algorithm on open space domain can be adapted to open space domain characteristics, and improve the accuracy of autofocus system and reliability. The fifth is a multi-threshold cumulative method improved identification method to enhance the color image tracking system to adapt to different environments track. Finally, the combination of these studies made improvements stereo vision image tracking system can be stable and accurate tracking of various objects.
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