The Structure Optimization And Light Weight Design Of The Car’s Sub-frame

Automobile is an important vehicle for travelling in the contemporary ages, people pay moreand more attention to its comfort and operation stability. As an important construction ofAuto-motive chassis, sub-frame carries various dynamic loading of the engine directly. There areisolation mountings on the sub-frame> automobile body and the connection of engine. The one onthe sub-frame can wear off the up and down shake of engine when the car works and the shakeof the car interior is recede, thus the automobile is more comfortable. Therefore, design ofsub-frame is an important part of the car overall design. This article will take sub-frame as objectof study, there is an analysis of sub-frame structure dynamics statics based on ANSYS software,make modification of the sub-frame through evolutionary structural optimization, to make thesub-frame satisfy various performance and realize lightweight.The research purpose of this article is take some sub-frame of Ladive as object of study,establish auxiliary frame geometry parametric model in ANSYS software which applying APDLlanguage，and get finite element model by mesh division; Establishing sub-frame coupleddynamics model of front suspension in ADAMS software，select damped condition as researchcondition of this article, get acting force of sub-frame and car body convection point throughsimulation; make analysis of statics strength to sub-frame on braking condition,as the beginningof optimization design; Select the optimization position of sub-frame according to the statictopology optimization density nephogram, and make parametric design to the optimizationresults; get stress volume to the size change of sensitivity through analysis of the sensitivity ofPDS module, then make size optimization; Calculate the sub-frame mode and frequency, maketopology optimization, which is based on improved frequency, according to the frequencydensity nephogram of sub-frame body articulation point near minus thin, to improve the naturalfrequency of sub-frame, so as to avoid resonance.Atfer making research of this article, make structure optimization of Shanghai Volkswagen sub-frame. As the calculation results show that, atfer using the optimized in this paper, improve the sub-frame inherentfrequency in the proof strength stiffness, and the volume9,05%less than the original model. This paper studiesprovides the optimization model to sub-frame design production enterprises, and also provides importantreferences for sub-frame design direction, making great importance for sub-frame production and design.