Design And Research Of Structure Parameter About SUV Rollover Performance

SUV not only has power and crossing over performance of off-road vehicles, butalso has comfort of cars. It can meet the needs of urban consumers who pursuit ofindividual style, also can meet the requirements of the rural and mountains which havepoor road conditions. So, SUV gets the favour of more people. But, the drawback ofSUV is easy to rollover compared to the other vehicles. Because it has a higher centerof gravity, and the tread has no corresponding increase. Therefore, it’s easy to rolloverat the condition of high-speed and sharp turn. In recent years, scholars have done a lotof work which adopted control measures to improve the rollover performance ofvehicle. But there is still a lot of improvement space in the vehicle itself structureparameters optimization matching. This paper starts from designing the parameters ofchassis structure and improves the rollover performance of vehicle by optimizing theparameters. This paper provides valuable reference recommendations for optimizingchassis structure parameters.This paper studies the rollover performance of SUV at the condition of high-speedand sharp turn, the main contents are as follows:(1) A parameterized model for the SUV is set up by Carsim. By analyzing thesimulation results of the slalom test, steering wheel angle step input test, steering wheelangle pulse input test, steady rotation test and turning back to the positive performancetest, these show the validity of the model.(2) Through the Isight integrated Carsim, contribution rate of the key parameters tothe lateral acceleration, roll angle and yaw rate and other rollover stability evaluationsare got at the working condition of fishhook by means of Optimal Latin hypercubedesign(Opt LHD). H, a, L, M, Ix, Iz, W, Hrc, Kf, Ka and Kr are key parameters thathave greater sensitivity on rollover stability of vehicle.(3) The key parameters are design variables. Lateral acceleration, roll angle and yawrate are objective functions. Using Isigh integrated Carsim, this paper adopts NSGA-Ⅱalgorithm for multi-objective optimization and obtain optimization results. Analyzecomparatively rollover performance indicators of before and after optimization at thecondition of fishhook, J-turn and double-lane change. The results showed that vehicle after optimized could steady the rollover motion of vehicle and prevent the SUVrollover effectively.