| With the widespread of computers and reversing engineering technology, CAD/CAM is implemented into stomatology restoration, and the manufacture of ceramic false teeth becomes feasible. The improvement of manufacture quality and efficiency changed the traditional stomatology restoration dramatically. The robot system for grinding the artifacial teeth prosthesis is the important part of the whole stomatology CAD/CAM system. The form-grinding technology of dental restoration is systematically studied in this thesis such as the design of dental restoration grinding robot system, the modeling and processing approaches for 3D data, the motion generation and interpolation methods, etc.By analyzing the manufacture process of teeth surface, the mechanical and controlling system of the 3D dental restoration grinding robot is designed. According to the geometric characteristics of the restoration, and the requirements of manufacture speed, a parallel structure with two grinding needles is adopted, which can realize 5-axis synchronism movement. The diamond needles can manufacture most kinds of materials including ceramic and porcelain. The flexible control system with PC and motion control card is developed. The kinematics model is built and corresponding working space and kinematic parameters are determined.Aiming at the pulse noise problem of scanned data of the 3D model for teeth restoration, the criterion of adjacent angle is introduced to indentify the pulse noise point and spline interpolation method is used to eliminate noise. Double-scanning is applied for the imperfection of the scanned data and ICP approach is used for data joint. Since there is precision problem in point to point registration by using the traditional ICP approach, a recurrent registration method based on the minimum distance between point sets and segment sets is proposed. The discrete point cloud data got by scanning will be registered and accurately spliced, partitioned by triangular grid, and then the polyhedral model in form of the triangular patches is built. The 3D data in STL format for direct grinding driving are transferred and stored.For the specific characteristic of the teeth surface, a motion generation method without confliction for parallel grinding of twin-burs is proposed. The velocities of the two burs are not interfered with each other and not kinematic conflicts exit in the grinding path. The fast searching and storing technologies of the polyhedral model data is studied. The Quard-tree method is implemented in the calculation of tool trajectory, a full-grid PR Quard-tree partition method is proposed. For restoration model of STL format, the searching efficiency of triangular cutter projected area facet in CLP calculation is improved, therefore the tool trajectory generation is speed up. With this method, the tool motion trajectory generation algorithms of the grinding tool are studied for flatted-bur, ball-bur and taper-bur, respectively. The tool trajectory generation method directly based on the point cloud data is also investigated.The interpolation method of the tool trajectory is investigated. According to the mechanism characteristics of the robot system, the Zigzag tool-path is modified, a stretch-bending B-spline interpolation method is proposed which restricted tool trajectory inside the arc drive surface, and the radial feeding velocity is adapted. The interpolation precision is guaranteed meanwhile reduced the grinding vibration.Finally grinding experiments are performed for kinds of typical teeth surfaces such as canine,incisor,cheek tooth and fore tooth. Based on the point cloud data obtained by scanning, the CAD model is generated with the methods mentioned above. And the dental restoration model is grinded using the designed robot system the whole system the corresponding algorithms are validated correct and feasible...
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