Research Of Key Technologies On Intelligent Coordinate Measuring Machine (CMM) Software

The measuring of products with free-form surface is being applied further in airplane industry, automobile, mold and so on. Coordinate Measurement Machine (CMM) is playing more and more important role in those industries because of its wide measuring scope, high precision and great efficiency. With the rapid development of manufacture automation, quite likely to become the next generation of CMM, Intelligent CMM is the kind of CMM that can finish measuring work automatically and guide the CNC modify the program.There are lots of flaws of CAD/CMM interface and measuring points distributing strategy on traditional CMM, so it has low efficiency and high cost. Because of this, the two key technologies of CMM are investigating emphases in the thesis.Basing on the demand of automatic production, System's interface and functions were projected. Mainly functions include eight parts: translation between CAD and CMM, measuring points distributing strategy, measuring path programming and so on. Every part was programmed particular.CAD/CMM interface is the information resource of CMM. The thesis analyzed the structure of IGES, got and translated data from it. Then, the inspecting part was modeled with OpenGL. It's the base of following work. Measuring distributing strategy is the keystone of CMM software.Measuring point dynamic distributing strategy was proposed. It's the creative work of the thesis. NURBS theory is the calculation base of the method. The strategy is different from other static distributing strategy. Because when the new measuring points generated, the forces of all points which have generated changed. In order to reach the stable condition, the points should modify their position themselves. Measuring points are in a dynamic equilibrium before the calculation finished. The feasibility and validity can be referred from the comparison of the strategy and others.The dynamic distributing strategy of surface and the successive generation method with a triangle-based hexagonal pattern in anticlockwise direction also were proposed. Each force of six sampling points as a hexagonal is the partial...