The Simulation Research Of Vehicle Rollover Prevention Based On AFS And DYC

Vehicle rollover may cause a significant loss of life and property, whichmakes it urgent to study how to prevent vehicle rollover. In order to improvevehicle stability, this paper focuses on the research of vehicle anti-rollover. Thecombination of Active Front Steering (AFS) and Direct Yaw-moment Control(DYC) to avoid vehicle rollover is proposed, and the idea is tested and verified inSIMULINK. At last, the results show that the combination of DYC and AFS is thebest way to prevent vehicle rollover, comparing with DYC or AFS alone.This paper mainly studies the methods of vehicle anti-rollover as following:First, analysis of domestic and international research of vehicle anti-rollovercontrol is carried out. After analysis and comparison of advantages anddisadvantages of Anti Roll Bar、Active Suspension、Active Front Steering (AFS)and Direct Yaw-moment Control (DYC), the combination of Active Front Steering(AFS) and Direct Yaw-moment Control (DYC) to avoid vehicle rollover isproposed.Second, based on the principles of vehicle “Tripped” rollover caused byUndersteer/Oversteer and “Untripped” rollover caused by large lateral acceleration,select yaw rate, vehicle slip angle, roll angle and roll rate as the control variables,and determine when vehicle is not stable and how to avoid vehicle rolloverproperly.Third, the research of vehicle stability control is based on vehicle dynamicsmodel. In MATLAB/SIMULINK, vehicle model and tire model is developed. Atthe same time, a similar model is built in CARSIM. Comparing to the results ofCARSIM model, SIMULINK model is proved to be correct.Fourth, elaborate the process of vehicle anti-rollover control, based on fuzzylogic control, as well as the principle of these two kinds of vehicle rollover, twodifferent controllers is designed in SIMULINK. One is for prevention of vehicle“Tripped” rollover, and the other one is for “Untripped” rollover.Fifth, as simulation tests vehicle is subjected to Sinusoidal steering、Stepsteering、J-Turn and Fish-hook maneuvers. After analysis of the simulation results,comparing with those of no control、AFS-control alone and DYC-control alone, the combination of Active Front Steering (AFS) and Direct Yaw-moment Control(DYC) is the best solution to vehicle rollover.Finally, obtain the conclusion of this thesis. Besides, point out what shouldbe further developed in the future.