Parameterized Design Of Bus Skeleton Based On Top-Down

With the coming of intelligent manufacturing,bus companies pay more and more attention to improve the efficiency of new product design,short development cycle and reduce costs.Top-Down design can realize product development process management.Compared to other design methods,the method of parametric design based on Top-Down can greatly meet the demand of Intelligent Manufacturing in modern manufacturing industry.Therefore,Top-Down design has become the mainstream of the CAD design industry nowdays.To improve the flexibility of the product design,it is the necessity and trend of the utilization of parametric,modular and intelligent design in the bus and coach enterprises for the new era.With the research object of a certain type of bus body skeleton,this thesis elaborates that a parametric design of the skeleton of bus body template which intergrated specification and practical engineering experience of bus enterprises is built,with applying Top-Down parameterized skeleton design idea.It has not only solved the non-parameterized modeling curve in the top skeleton model replacement question,but also realized the different modeling curve geometric parameter associated design of bus body skeleton.The parametric design of the skeleton of bus body template has been developed base don Windows 7 system,which used Automation API and Database management technology under the Visual Basic 6.0 integrated development environment and built on the platform of the CATIA V5.The main issues in this study are investigated as follows:(1)The idea of parametric design based on Top-Down were researched,combined with CATIA secondary development method,theory of parametric design,parametric design level of CATIA and key techniques of CATIA parametric design,lay the foundation for the realization of parametric design template of the body skeleton;(2)The process of parametric design for the body framework which based on the structural characteristics of body frame and Top-Down design was formulated.A new method is introduced to solve the parametric design of the skeleton of bus body which driven by modeling-curve.It can make up defects that the current coach parametric design model is unable to import external modeling-curve and replace modeling-curve;(3)The custom section material library based on structure design modular of CATIA V5 was developed,according to the actual requirements of GB and bus enterprises.The system of friendly human-computer interactive interface was developed,based on parametric design of the skeleton of bus body template.(4)The establishment of friendly parameterized template model for bus frame,shorten the response time of enterprises in response to customer needs and meet the needs of customers individuality,consistent with improving the flexibility of body frame design and promoting enterprises to achieve efficiently aim of remodeled design.