Parametric Design And Rollover Simulation Analysis Of Bus Body Frame Based On Modularization

This paper takes a passenger car as the research object and builds a parametric model of the vehicle body skeleton module based on the CATIA platform and Top-Down parametric design method,combined with the method of module division based on the closed-loop structure.At the same time,according to the national standard and to meet the actual needs of passenger car production,bus body skeleton profile library has been developed,the usage of user-defined features in parameterization of bus body skeleton is studied.The method of dividing the traditional six modules of carrying bus is studied,a method of modular bus body based on closed-loop structure is proposed.According to the body frame before and after the bridge and the door four main load-bearing section to decompose the bus body,and a bus body module based on a closed loop structure is established.At the same time,the finite element model of the body section was established and the simulation of the rollover process was carried out to verify the rationality of the modular body structure.The main contents of this paper are as follows:(1)The modular and parametric design principles,key technologies and guidelines,and the technical and economic significance of modularization and parameterization are summarized.which laid the theoretical foundation for the realization of modularization and parametric design of body skeleton.(2)The traditional bus body modular division method was studied.In the traditional passenger car modular division method,the vehicle is composed of six large pieces of welding,However,the welding connection affected the transmission of force and affected the safety performance of the superstructure of the passenger car.The effective arrangement of the closed loop can significantly improve the rigidity of the bus body,and the greatest demand for the three-dimensional modeling of the bus body skeleton at the present stage of the modern bus company is to realize the modular design rather than the traditional six-piece partition modeling idea.Therefore,Modular design of bus body based on closed-loop structure was proposed.(3)Exploration of New Passenger Vehicle Parametric Modeling Method.The advantages and disadvantages of parametric modeling using structural design(STD)module are researched and analyzed.Based on this,a new method to establish parameterized skeleton of passenger car body with generative surface design(GSD)Parametric design provides a new idea.On this basis,a new method to establish the parameterized skeleton of passenger car body with generative surface design(GSD)module is put forward,which provides a new idea for the parameterized design of the bus body skeleton.(4)The parametric model of vehicle body skeleton is established by using GSD module combined with the module parameterization method based on closed loop dividing the bus body structure.Then the local model of the body section was intercepted and its finite element simulation model was established.Based on the passenger rollover laws and regulations,the safety analysis of the rollover collision process was carried out to verify the effectiveness of the parametric structure of the body module.(5)The rollover simulation results are analyzed,the parameterized structure of the bus module is optimized,and the optimization effect is verified.The design concepts and methods proposed in this paper improve the flexibility of design,promote the serialization,generalization and standardization of products,and facilitate.It is convenient for the same car to be modified and designed to effectively shorten the development cycle of the entire vehicle design and greatly improve the efficiency.It is of great reference significance in actual engineering use.