Performance Analysis And Parameterization Lightweight Optimization Design For Car Suspension Control Arm

With the advancement of automobile independent research and development in recentyears, our country has made good achievements in the field of automobile bodyindependent research and development. But the ability of automobile chassis independentresearch and development is still quite weak due to reasons such as capital, talent andtechnology. In addition, with the development of automobile industry, the problems ofresource and environment are increasingly severe. The lightweight of automobile is theeffective way to cope with these problems. As an important component of automobile, thelightweight of chassis parts is extraordinarily significant to reduce automobile weight.Therefore, the lightweight of chassis parts has been attached great importance in the fieldof domestic automobile chassis research and development.This paper was completed based on the project of “Car Chassis Parts ComprehensivePerformance Matching and Lightweight Design Research”(NO.20126004), which was amajor project of science and technology development of Jilin province. Through virtualprototype technology, a rigid model of a car was built, including front suspensionsubsystem, rear suspension subsystem, powertrain subsystem, steering subsystem,horizontal stabilizer bar subsystem, tire subsystem, braking subsystem, car body subsystem,etc. At the same time, the suspension control arm was generated as elastic part with FEAmethod. Furthermore a rigid-flexible coupling virtual prototype model of a car was builtconsidering the elastic front suspension control arm.According to National Standard “Method of Random Input Running Test AutomotiveRide Comfort” and “Controllability and Stability Test Procedure for Automobiles”,relative simulations of the built rigid-flexible coupling virtual prototype car model wereperformed and detailed comparison between simulation results and vehicle experiment datawas made to verify the validity of that model. Dynamic simulations of the verified rigid-flexible coupling car model wereimplemented, which is to extract dynamic load of joint points of control arm inaccelerating, braking, stable steering and uniform linear working conditions. Free modalsimulated analysis and experiment were both carried out. In addition, other simulatedanalysis of control arm such as structure strength performance and transfer characteristicperformance were also accomplished to determine the performance of control arm beforeoptimization，which provide the basis for performance comparison after optimization.Topology optimization of control arm was accomplished and a new control armtopological structure was obtained. This topological model was parameterized incommercial software Meshworks/Morpher. What’s more, multi-objective size optimizationof parameterized control arm model was carried out to obtain the scheme of lightweightdesign.After optimization, simulated analysis of control arm including structure strengthperformance, free modal performance and transfer characteristic performance wereperformed to meet performance requirement by comparing the result before optimization.Moreover，ride comfort and stable steering simulations of rigid-flexible coupling virtualprototype car model considering elastic lightweight control arm were conducted andcomparison between results before and after optimization was made. It was found thatresults were in good agreement with each other. It turns out to be that the mass of controlarm reduced by15.6%while relative performances meet design requirements.