Research On The Method Of Testing And Evaluating Of The Large Bus Electronic Stability Program

Due to the large bus’s centroid position and the high structural complexity, it easy to cause skid or rollover and trigger the heavy accidents when the bus avoiding obstacles at high speeds, overtaking or conditions such as high-speed cornering. The vehicle electronic stability program (ESP) can improve vehicle stability, reduce and prevent the occurrence of accidents and corrected by controlling the steering of the vehicle when the bus understeer and oversteer. Vehicle electronic stability program required the real vehicle testing and the method in a particular experimental site to test and to evaluate the performance of the vehicle. The large vehicles that equipped with electronic stability program are low in the domestic, uniform testing and evaluation of experimental methods match is not formed. This article relies on Beijing Traffic dynamics Square, adopts the mathematical simulation software Matlab/Simulink and vehicle dynamics software Trucksim, analyzes and researches the large passenger electronic stability program matching testing with the method of theoretical simulations and real vehicle testing, the main research steps and reads as follows:(1) Dynamics modeling and verification. It built the Foton Europe V-BJ6940 passenger models in vehicle dynamics software, including the height of the center of mass of the vehicle, the powertrain, the brakes, the suspension model and the characteristics of KC. By comparing the real vehicle experiments and the simulation tests to verify the accuracy of the model.(2) ESP control and validation model. Based on the Trucksim/Simulink, it established the ESP control model. According to the ESP control theories, it analyzed the typical operating conditions and the instability factors. It researched the nominal yaw rate, the nominal slip angle and the yaw moment and verified the ESP accuracy by simulation experiment.(3) Research on the program of the ESP testing. Through learning the FMVSS126 regulations and the characteristics of large passenger vehicles, proposed pilot the program to test passenger’s ESP-the improved sine with dwell and analyzed every detail of the test, including the test speed, the steering wheel frequency, the stagnation point, the stagnation time,the trial road and the vehicle’s state before subsequent processing of experimental. By analyzing the statistical probability theory, the test used the yaw angular velocity decay rate and the lateral displacement of the particular time to evaluate the performance of the large passenger ESP.(4) Simulation and the results of analysis and the expansion of the testing, using the validated model and the ESP control model to study the proposed test method that improved sine with dwell, by analyzing the decay rate of the yaw rate and the lateral displacement of the particular time to verify the experimental method’s feasibility. On this basis, took the different tonnage passengers in the JTG B05-01-2013 to conduct the sine with dwell testing. The results showed that the improved test methods suit for the large passenger ESP matching experiments that the total mass less than 25t, the centroid height less than 1.5m of, it do not suit for the large passenger ESP matching experiments that the total mass more than 25t, the centroid height more than 1.5m.