The Suspension Optimization of FSAE Racing Car Based on Virtual Prototyping Technology

摘要

Research and/or Engineering Questions/Objective: One important design goal of racing car suspension is to keep the tire perpendicular to the ground which needs an accurate kinematic design of suspension. This paper details the simulation method of FSAE racing car based on MSC.ADAMS and VI-Motor-sport, then the optimization of suspension kinematic characteristic could be conducted. Meanwhile, the paper will show the effect of suspension kinematic characteristic on lap time. Then the problem that the developing period of FSAE racing car is not long enough to conduct sample prototype test can be solved by the performance prediction and optimization by virtual prototyping technology. Methodology: The virtual prototyping model of BIT FSAE racing car and a certain race track were built by multi-body dynamics simulation software MSC.ADAMS and professional racing car simulation software VI-Motorsport. During the modelling process, the non-linear mechanical characteristic of tires was taken into consideration by the tire data provided by FSAE TTC, as well as the aerodynamic characteristics. The correctness of the model was verified by the "g-g" diagram collected by data logger in competition, then the further analysis and optimization could be conducted based on these. The comparison of lap time between the original race car and the race car after optimization was also conducted by simulation. Results: The comparison of lap time simulation results shows that the grip of tire during turn is increased after optimization of suspension, and the lap time is reduced. Limitations of this study: The simulation is based on multi-body dynamics simulation which assumes the chassis and suspension as rigid body. It brings some errors because the compliance characteristic of chassis and suspension is ignored. What does the paper offer that is new in the field in comparison to other works of the author: In previous technical papers in FSAE racing car field, there is no precise comparison between simulation results and actual data. But in this paper, the correctness of the model was verified by the comparison between simulation results and actual data collected in competition. And in this paper, the "g-g" diagram of FSAE racing car was first presented and discussed which is vital important of racing car performance. Conclusion: The simulation of FSAE racing car lap time based on MSC.ADAMS and VI-Motorsport has a high accuracy which could provide a possibility of performance prediction. It can shorten the developing period of FSAE racing car and improve the performance of FSAE racing car. Furthermore, the designers can adjust the kinematic design of suspension to meet different requirements in different race tracks by the proposed method.