Research On Distributed CAD System Based On Web Technology For Cam Mechanism

With the development and popularization of Internet/Intranet, computer aided design (CAD) system, as an important part of computer integrated manufacturing system (CIMS), has been changing quickly. How to build the environment in which we can satisfy with the requirements of design and manufacturing in different places, to connect the design, manufacturing, management and distribution as well as sharing information, and to make the function of CAD software system more integrated, more intelligent and more cooperative, all of these bring a challenge to the research and development of CAD system. On the background of the research project named the new designing method of cam mechanism and the development of CAD/CAM software, which is supported by the opening funding of State Key Laboratory of Mechanical Transmission in Chongqing University, this paper researches the implementing method and key technique of developing network distributed CAD software system based on Web technology for cam mechanism. The main working and conclusions in this paper are as follows:(1) On the discussion of cooperative designing method in networking environment, we put forward the system modeling method and the general scheme according to requirements of research project.(2)This paper presents a system structure which combine the two-layer Client/Server structure with the three-layer Browser/Web/Server structure, to make the foundation for CIMSfunction such as information share among the design, manufacturing, management and distribution, integration of CAD/CAM/CAPP and cooperative design.(3) The paper researches designing method of the motion rule-divisible cam mechanism, makes a detailed analysis of the mathematical equation, and builds the mathematical model of the cam mechanism.(4)The paper discusses the modeling method of the parts based on feature technology. According to the research issue, we analyzed the characteristic of cam mechanism modeling based on feature, put forward a new modeling method- a compound modeling method based on motion features and shape features. During the design, the designer just input the motion feature parameters according to each course section of the cam mechanism and the basic dimension parameters of the cam mechanism, then he'll finish the modeling of the cam mechanism. The designer can divide and combine the motion rules in forward course and backward course of the cam mechanism randomly, realize the design of the cam mechanism under the complex working conditions, enhance the designing automation and adaptability of cam mechanism in a high degree, and the design is very directly and convenient.(5)The paper researches the key technology used in the software development, including ARX programming technology, object-oriented programming technology, database technology, technology of the system structure which combine two-layer Client/Server structure with three-layer Browser/Web/Server structure, and so on, makes the system a good structure, and modularize the function of the software.(6) The paper introduces the ASP technology and it's components in detail, researches how to use ASP technology to develop Web application, and how to use ASP component-ADO to access the station database, to realize the long-distance access to the database based on Web technology, and realize the share of the designing information.(7) The paper introduces the software environment and running process, provides the running examples. All of these show the system design is correct, the user interface is friendly, the system has strong practicability in actual design.