Research On Fast Design Technology Of Body Structure Based On Section Optimization

In the conceptual design stage of automobile body,the main section design runs through the whole body development process because of describing the structural characteristics of the body beam and the assembly relationship.Although we can learn from the design experience of mature benchmark models,the traditional body design process is still too complex and relies on the experience judgment and experimental simulation methods of designers,and the errors in the design process often affect the quality of body development ultimately due to the late reflection.Therefore,in the main section design process of the body concept design phase,based on the section design of mature benchmark models,the introduction of the body section optimization design technology and the section quick matching method is of great practical significance to improve the quality and efficiency of the body structure design.In this paper,the main section design method of the body is taken as the research object,the body structure of the passenger car is analyzed and the main section division standard and definition principle of the body are determined,and the main section library is established based on mature benchmarking model.On the basis of the theory of curve curvature change,according to the curvature recognition method,the curve sections in the body section are classified and judged,the section curves are simplified according to different curve types and the simplified section data are output,so that the reference section can meet the requirements of the section parametric design.Based on the simplified data of parametric section,the calculation method of section performance parameters that affect the body mass and stiffness is derived,and the proportional vector method is introduced as the control method of section shape optimization,combined with genetic algorithm,the light weight design of the reference section is carried out under the constraint of stiffness performance parameters.Then the section representation method is used to complete the reconstruction of the optimized section shape,and the body wireframe model is established according to the new model surface and the matching datum point of the section is determined.Based on the coordinate transformation theory of 3d spatial graph,a quick matching and alignment technique for the optimized cross section graph and wireframe model is established.Based on the above for the study of the theory of the cross section design,this paper,by using the database management with UG secondary development platform,body section and quick design system is designed and developed,has been demonstrated and the reference section of the simplified processing,optimization of car body design and the optimization of output by using the results of the process section,to prove the practicability of the system.