Research And Implement Of Bridge Crane CAD System Based On Knowledge

With more than half a century's development of CAD technology ,it has a remarkable progress in theory , technology , applications aspects, however, the geometric modeling-based CAD system would be unable to have a integration of field knowledge to design and impossible to achieve reuse of knowledge-based resources. KBE system for traditional CAD system proposed solutions to the existing problems, such as the design principles embodied, knowledge-based resources reusing.It can provide optimized design as well.The key to the design of KBE system is rational and efficient expression, use and accessing design knowledge. Mechanical product design knowledge is rich and diverse, but which decided to the survival and development of enterprises is the design experience and skills have accumulated over a long period by engineers. Based on the research of case-based reasoning (Case-basedReasoning. listed CBR) technology, applying the Case-based reasoning technology to knowledge-based CAD system for cranes, which can use the solution to solve current problems directly, rule acquisition and translation difficulties can be avoided to some extent, which can take better advantage of knowledge resources.The different types of knowledge are involved in product design, including empirical, knowledge and structural knowledge, single method will be not enough to express knowledge of design , synthesis consideration of the ability of expression, resoning and maintainability of the knowledge, the mothod of object-oriented expression of the knowledge is the integration of various methods. View the characteristics of XML, having a exploration of the expression of knowledge based on XML. Using XML to express knowledge and case of crane, and achived to integrated the crane design knowledge into the CAD system. So that the designer can access to knowledge conveniently, and have a facilitate network sharing of knowledge resources.Aimd at lowering the difficulties of features revisal in case-based reasonmg system, the establishment of 3d template of bridge crane product is attempted based on the deep study of 3d parametric design, the API tools of Solidworks software is used to have a second exploitation. Have a research in the method of using the parametric to rewritten the case by the knowledge and experience be encapsulated in the model example, similar cases have been rewritten to have a 3D model which meet the design requirements.