| The manufacturing products in the current information age have such two kinds of different representations as information model and real product, while the most innovative and valuable part of the manufacturing is included in the former one. This is the case especially for the freeform surface parts which are widely used in modern industry. Thus such research work as the measuring, modeling, manufacturing and quality assessment of freeform surface parts is of great importance in modern manufacturing industry. In this dissertation, based on the survey of the present research situation and development trends at home and abroad of the numerical control measurement methods, measurement layout, surface modeling, the integration technology of measuring, modeling and manufacturing of freeform surface parts, by absorbing techniques such as computer vision, precision mechanism, photoelectron, CAD/CAM and automatic control, etc., a non-contact numerical control measurement prototype system using probe of laser spot-source and an integration system of non-contact measurement and manufacturing of freeform surface based on the existing numerical control milling machine were developed, meanwhile the relevant problems on the measuring, modeling, manufacturing and inspection of the freeform surface parts are profoundly studied.The main contributions of this dissertation are briefly presented as follows:1. The rapid, precise and adaptive measurement of freeform surface is the primary problem to solve in its digital manufacturing. Thus, the measurement principle of the probe of laser spot-source and the method to collect the coordinates of freeform surface were firstly analyzed. Then, a multi-pattern adaptive measurement planning method in one dimension and a rectangle -adaptive measurement planning method in two dimensions were put forward and simulated so as to minimize the number of measurement points under certain measurement accuracy. An automatic tracing measurement method of the boundary of measurement area was proposed thus to optimize the measurement path and reconstruct the measurement points. The concept of scanning reflex vertex and monotone chains were used in the optimization of the measurement path of freeform surface, moreover, the effectiveness of the method was verified by example.2. To filter noise in the huge amounts of measurement points by non-contact measurement method and compress, segment and smooth the measurement points, a fuzzy weighted average filter method using fuzzy membership idea to optimize the weights by iteration method was proposed. Compared with average filter method, the method can eliminate the noise information in the measurement points more effectively. A data compression method was proposed to compress the measurement points that include huge redundancy under certain accuracy. Then segmentation and smoothing method for the measurement points to identify the jump edge, crease edge and smooth edge and optimize the measurement points were conducted so as to reconstruct the surface and generate the manufacturing path conveniently.3. NURBS reconstruction of measurement points, the measurement data after pre-filter were fitted with non-uniform rational B-spline curves with modification of the objective function, iteration method and optimization of the number of control points. The B-spline curves obtained were compromised and skinned to acquire the NURBS representation of the surface and then were transformed into standard IGES format to further dispose the measured surface with commercial CAD/CAM software. The results of computer simulation and experiment verified theeffectiveness of the method. In addition, the surface merging method and accuracy assessment method of the reconstructed surface were studied.4. The method to plan the manufacturing path directly from the measurement points was studied. The key geometry information such as normal vector and main curvature etc. were firstly calculated by local approximation of measurement points wi...
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