Research On Registration Method Of Point Cloud Data And Key Technology In Vision Measurement

Multiple-views registration point cloud data is one of the indispensible parts of 3D topography measurement and 3D reconstruction. So in this paper, according to the characteristics of encoded structured-light of 3D measurement system set up in the lab which is noted for high accuracy, fast registration speed as well as application for integral measurement of industrial component,registration method of point cloud data on optical and key technology are researched.Base on summarizing domestic and overseas status of technology of obtaining point cloud data, registering point cloud data and 3D reconstruction, the registration method base on feature marked point in theory is analysed,and the author designs a plan for feature marked point image processing; the simulation result validated the correctness of this method. Finally, register the multiple-views point cloud data by real test. This paper studies the specific contents include the following three aspects:1. The fast and accurate marked point location is an important premise to register. The marked point selection, grayscale, image smoothing, threshold segmentation, edge detection and center location of the circles are analyzed in this paper. In the image smoothing part, the median filtering method is chosen after comparing the applicability of some filter methods. In the center location of the circle, designs the least square method for ellipse fitting validated this by experiment.2. In this paper, the degree of accuracy and speed of registration method base on marked point in theory is analysed, such as three points method,four points method,quaternion method and SVD least squares method. It designs an evaluation plan for degree of accuracy base on overlap ratio of marked point. The merit and demerit are evaluated by simulation, in the end SVD least squares are chosen as the registration method of 3D measurement system.3. The measure software on the basis of hardware of measurement system is programed. In the lab condition, the experiment of farmer gypsum statue by 3D measurement and registration is test; it obtains the good reconstruct surface visually, in the meantime, evaluating the degree of accuracy with overlap ratio of marked point.