| With the development of computer technology, the global manufacture era is coming. Under this background, using integrated and intelligent CAD systems to accomplish product design is important ensure for the enterprises to win the market competition. Therefore the study on integrated and intelligent CAD systems has become the trend in design field.The design problem is essentially a constraint satisfaction problem. Given the functional, structural, material, manufacturing constraints and so on, find the details of design object in line with the design requirements. Current CAD systems are good at dealing with complicated part drawings, but are week in the design of assembly drawings. However, assembly drawing is an important technical file, which contributes to improve design efficiency and shorten design cycle.Our discussion is focused on parts library technology based on network and assembly constraint satisfaction problem (ACSP). In this paper we present a deep study on integrated ICAD and build a parametric design system of assembly drawing based on PPLD3 (Parametric Parts Library).Firstly, the background and related work in the field of integrated ICAD research are introduced. The architecture of parametric design system of assembly drawing based on PPLJB is set up using the object oriented modeling method. And the functional model of parametric design system is built using the IDEFO structural analysis approach.Then based on the deep study on PLIB standards, the product information model based on PLIB is set up using the tools such as NIST Expresso, WinSTEP and so on. To support the collaborative design and the share of design resource, the second integration project suggested by the PLIB standards is selected and modified and the information integration system based on PLIB is set up. The information exchange between different CAD systems is implemented.The geometric model of products is set up by studying on CSP. The simplified method for geometric constraint system is presented and a graph representation is used todescribe the geometric constraint system. The characteristics of the geometric constraint network is also given. A part drawing oriented geometric reasoning algorithm based on point-cluster reduction presented and a local constraint solver is set up. It can obtain the solving sequence of geometric elements from the geometric constraint network and achieve the parametric design of complicated drawings. The tool for building PPLB is set up using the local constraint solver and PLJB technology.The solving mechanism of ACSP is discussed and the global constraint solving algorithm based on block is proposed. The 2D constraint solver is built based on the local constraint solver and PPLBB to achieve the parametric design of assembly drawing.Finally, under the practical background of the project of GIS parametric design software, the development of the parametric design system of assembly drawing based on PPLJB is carried out. The future work in this area is addressed.In conclusion, there are some innovates listed below in this paper.1. The architecture of assembly drawing design system which supports bottom-up and top-down assembly design is set up;2. The parametric geometric model of product based on constraint is set up, and the solving model based on constraint network graph for the product geometric model is proposed;3. The parametric information model of product based on PUB is set up, the method of product information exchange between different CAD systems through PLJB is designed, and the integration of parts libraries between the different CAD systems is implemented;4. The geometric reasoning algorithm based on point-cluster reduction is put forward, and the local solver is set up based on it, the local constraint solving problem is solved;5. The global constraint solving algorithm based on block is proposed, and the 2D constraint solver is set up, the parametric design of assembly drawing is realized.
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