| Tianjin FAW Xiali Automobile Co., Ltd. is a mini-car production base, mainly for economy cars. In order to keep the vitality and competitiveness of Xiali brand and hold the leading position in the economy car market, Tianjin FAW Xiali Automobile Co., Ltd develop CA7130 (target cars)in 2006.It is the next generation XiaLi car. Parameter design and matching of suspension system and suspension kinematical characteristic (especially change of wheel alignment parameters) are important impact factors of handling and stability of the vehicle. So research on matching parameters of the suspension system is very necessary. The topic design the structure and match the parameters with simulation analysis and manipulation of stability test, base on the target car's overall design requirements for target car. The suspension system designs to ensure that target car has good comfort and handling stability with a shorter development cycles and lower development costs. It complete the design task assigned by the company. At the same time, through this work, a relatively complete set of suspension system design approach formed and grounded for future work.In this paper, the main contents include the following aspects:(1) In this paper, the general idea of matching parameters of the target car suspension system is determined, basis of relevant data to domestic and foreign vehicle suspension system Matching. The type and characteristics of target car suspension structure are described. According to the general requirements of suspension design, the suspension stiffness, migraine frequency, roll stiffness, roll angle, the relative damping coefficient of shock absorber and the general range of values are confirmed with the car theory and the car design related theories, combined with my years of experience of suspension design, considering the comfort and handling stability of vehicle suspension system. The better parameters of dynamic performance for ADAMS simulation analysis on the target car are offered.(2) The ADAMS simulation software is described briefly in this paper. The idea of the establishment of dynamic model with ADAMS software is described. Parameters needed by the establishment of goals sedan model and methods of obtained are introduced. A target car virtual prototype simulation model, including the former suspension, rear suspension, steering systems, front and rear wheels and the body, etc. is established with ADAMS/ CAR module. It grounded for analyses of the suspension system characteristics and the simulation of handling stability.(3) The suspension system characteristics and the simulation of handling stability are analyzed with the target cars simulation model in this paper.Through simulation, Kinematic simulation analysis of suspension system mainly include analysis of Kingpin inclination, Caster, front toe, wheel camber, and the amount of lateral slip with the wheel up and down trends, the impact of handling stability by the parameters and the general range. Through the motion analysis, verify that the wheel alignment parameters of target car suspension system is reasonable with the wheels up and down and that are consistent with the ideal location parameters trend. In order to ensure objective car achieve the design characteristics of the desired capacity, through the kinematical simulation analysis, the layout optimization solutions is provided to suspension systems-oriented institutions.The handling stability simulation on the target vehicle virtual prototype model is in accordance with GB 6323-1994 "Test Method for vehicle handling and stability" and the relevant provisions. The suspension parameters on the impact of vehicle handling and stability is analysis mainly through the steady-state rotation simulation, the steering wheel angle under the step input transient steering response simulation, the steering wheel angle pulse simulation, turning back simulation and snake-like turning light test simulation. In accordance with national standard QC/T 480-1999 "vehicle handling and stability Index limits and evaluation methods" and the relevant provisions of the stability, the level of vehicle handling and stability is evaluated, in order to provide a theoretical basis to improve optimization of suspension parameters. Two different diameters stabilizer bars are compared in this paper. Contrastive analysis of steady-state rotation simulation between these two programs are carried out to determine to increase front and rear stabilizer bar diameter moderately, making the trend of understeer bigger and the inclination of the car body significantly reduce when the car turn big bend.(4) In this paper, comparison test results of the linear zone stability of mechanical model cars, car-like vehicles and pairs of standard reference models are calibrated and analyzed. And two different diameter stabilizer bars steady-state rotation test program is also comparatively analyzed. It is a similar trend of the results of its understeer gradient and body roll steering gradient test and simulation analysis. Results show that the understeer gradient U and the lack of body roll steering gradient Kφof the stabilizer improved are greater than its pre-improvement. It is very close to the Standard target reaching the design requirement.The innovation of this paper is that it is for a car of Tianjin FAW, using the combining method of experience design, simulation analysis and the manipulation of the stability road test to match and design suspension system for the aim car suspension system achieving the coherence of the targeted manipulation of stability, smoothness and economy.The research projects combined the traditional suspension system experience design, virtual prototype simulation analysis and the road test of handling and stability to reduce product development costs and risk, shorten the suspension design period, make better use of enterprise existing products resources. Through the topics, we can summarize a practical design approach of suspension, laying a solid foundation for the future development of new models of suspension, being important in engineering.
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