The optimization of electric power assisted steering to improve vehicle performance

Abstract

To investigate the e ects of electric power assisted steering ( EPAS ) on a vehicle's steering performance, this paper explicitly proposes several indices, such as steering sensitivity and road feel, for evaluation of steering performance. Then a single-track car model with lateral and yaw movement is considered and an EPAS model is built. The mathematical expressions for the steering performance indices are deduced and a stability criterion is established by integrated analysis of the vehicle's dynamics and the EPAS dynamics. By means of frequency domain analysis, the e ect of each parameter of EPAS on steering performance indices is analysed. Finally, an optimizing model used to improve these steering indices is put forward and the result is given.

A Research on Impact Compensation Control Strategy of Electric Power Steering System Based on Whole Vehicle Dynamics

“…This chapter based on artificial immune system with the pavement impact compensation control strategy, but the basic idea of literature from control of the RTSS estimation method [3]. In order to research the EPS in the pavement shock signal under all the performance of interference, the need for research, first to fix the steering wheel, the simplified model for EPS at this time [5]:…”

Electrical power steering – modelling and bench testing

“…The authors of article [8] proposed two indicators -steering sensitivity and road feel -in order to assess the performance of the steering system. It was found that steering sensitivity depends on the following factors: stiffness of the torque sensor, the electrical characteristics of the propulsion engine, its moment of inertia, the transmission ratio of the power steering, the boost control and the vehicle parameters.…”

Model development and parameter investigation of a column-type electric power steering system

“…Great progress has been made in the control system of EPS developing and designing, but few discussions have been made on the research and optimization of the parameters on the vehicle controllability and stability. Liu, et al [7] analyzed the influence of some parameters of EPS, but the effect of other parameters, including the inductance, the torque constant and resistance of the motor, on steering sensitivity and road feel have not been studied. To design and improve the EPS system performance, it is necessary to study the parameters of the EPS system further.…”