Research On The Stability Control Strategy Of Tire Blow-out Vehicle

Tire blowout is a main cause of traffic accidents.Due to the sudden occurrence of tire blowout,drivers often misoperate in panic.Therefore,it will lead to major traffic accidents.In view of this problem,this thesis studies the stability control of tire blow-out vehicles.At present,there are three main problems in the research of tire blow-out vehicles stability control.The first one is that the whole vehicle model used in the research is not accurate enough,so it will directly influence the control results.The second one is that existing researches fail to take into account the problem that the vehicle stability state variables are difficult to obtain directly in engineering practice.For example,most of the existing studies directly default to the sideslip angle as a directly obtained variable,but in practice it is difficult to directly obtain.The third one is that the stability control of tire blow-out vehicles is mostly based on a single control approach.But for the extreme condition of tire blowout,a single control method is difficult to achieve the desired control effect.In view of the above problems,this thesis proposes the following solutions:Firstly,in order to achieve high accuracy of the vehicle model,the vehicle dynamics simulation software Carsim is used to build the whole vehicle model.Considering that the original tire model of Carsim can not be well suited to extreme conditions,the Unitire model is built in Simulink,and the Unitire is embedded into Carsim by using Simulink interface of Carsim.At the same time,considering the poor performance of Carsim's original steering system,a simulation model of electric power steering system is established,which is widely used at present.Similarly,it is embedded in Carsim software to build a joint simulation model,which lays a foundation for the subsequent study.Secondly,considering that the vehicle is a very complex non-linear system,a non-linear observer is established to observe the state variables of vehicle stability,and its accuracy is verified.Then,the simulation results are compared with those obtained by extended kalman filter,which verifies the superiority of the designed non-linear observer.Finally,in view of the fact that the previous studies on tire blow-out stability control are mostly based on single brake control or single steering control,but the control effect of a single control method is limited.Therefore,this thesis combines the above two control ideas to construct a joint control method of inner loop differential braking control and outer loop trajectory control.The simulation results prove the superiority of the joint control method.