The Design And Research Of Dynamical Characteristics On Redundant Steering System For Electric Vehicles

In recent years,vehicle accidents caused by the failure of steering system control units have become increasingly prominent.With the continuous development of intelligent driving technology,people have a higher demand for the safety of automotive steering system.Redundant steering system has become a new research focus of automotive steering system with its advantages of high efficiency,high reliability and energy saving.Compared with the Electric Power Steering system（EPS）,the redundant Steering system designed in this paper can effectively avoid the Steering failure caused by the failure of one component through the redundant design of software and hardware of electronic components such as the Power motor and control unit.Thus improve the safety and reliability of steering system.The main research contents include:Firstly,the overall structure of the redundant steering system was designed,the key components of the redundant steering system were briefly introduced,and the modeling and assembly of gear rack,worm wheel and worm were completed.Secondly,the finite element software ANSYS was used to complete the strength check of each key component under the limit working condition.ADAMS was used to establish the virtual prototype of the rack and pinion mechanism of redundant steering system,and the basic performance of the steering wheel number,rack stroke,steering smoothness,line Angle transmission ratio and so on were simulated.Then,on the basis of the theoretical analysis of the power characteristics,the speed induction coefficient under the characteristic speed was fitted to get the speed induction coefficient under the full speed,and the design of the power curve of the redundant steering system was completed.The control model of dual-circuit redundant steering system was built in Simulink software,and the current control effect of the control system was verified.Finally,a co-simulation model of redundant steering system was established,and a series of fault tolerance and power performance simulations were carried out based on the model,and the bench test of steering system was completed.The results show that the designed redundant steering system has good power assist performance and fault tolerance,and meets the requirements of the steering system.