Structure Design And Optimization Of Macpherson Suspension System Based On Virtual Prototype

Suspension design is the most important content of the car chassis design .Suspension is the soul of chassis .So it is important to research and analysis suspension K&C characteristics. Suspension K&C characteristic directly affects vehicle driving performance and occupies an extremely important role in car dynamics field. It has a vital role and significance on the improvement of vehicle handling and stability. This paper uses the thought of the synthesis method and experimental optimization method. Through virtual prototype analysis software ADAMS/Car, the paper builds suspension and vehicle model, and then simulates and analyzes the model. Then decompose vehicle performance objectives, so the paper can optimize suspension K characteristics through adjusting hard point with ADAMS/Insight and optimize suspension C characteristics through experimental optimization method.In the traditional design process, complete, or almost complete, vehicle concepts are analyzed to see if they meet the performance targets. But the synthesis method can. With the synthesis method, people can determine the vehicle performance according to the same kind of vehicle in the market. Then use computer analysis and test, and the vehicle performance can decompose to each vehicle subsystem. If each vehicle subsystem can meet the performance requirements, vehicle performance can also meet the requirements.This paper designs and optimizes suspension through the synthesis method. First, the paper builds front and rear suspension model and tests the model. The test data is from JLU-II Suspension K&C Characteristic Parameter Test Rig. Then it builds sample car model and analyzes and tests the model in handling and stability performance.According to the vehicle performance analysis and target decomposition with experimental and optimization, the paper sets target of suspension K&C characteristics performance. The suspension K characteristics performance includes front and rear axle toe rate with wheel travel, front and rear axle camber rate with wheel travel. The suspension C characteristics performance includes front and rear axle toe rate with lateral force. Then the performance of sample car can contrast with the target.Analyze the K characteristic sensitivity of front and rear suspension. The contents of sensitivity analysis conclude front and rear axle toe rate with wheel travel, front and rear axle camber rate with wheel travel. Then find significant factors and set response target in ADAMS/insight. Optimize suspension K characteristics through adjusting the hard points. Simulate and analyze in ADAMS/insight with significant factors. Export the result in HTML and adjust hard points until response can meet the target. According to the result, contrast the adjusted curve with the target curve. Analyze the C characteristic sensitivity of front and rear suspension and optimizate it. The contents of sensitivity analysis conclude front and rear axle toe rate with lateral force. According to the result, contrast the adjusted curve with the target curve.