Steering Wheel Torque Control of Steer-by-Wire System for Steering Feel

A mathematical model of steering feel based on a hysteresis model is proposed for Steer-by-Wire systems. The normalized Bouc-Wen hysteresis model is used to describe the steering wheel torque feedback to the driver. By modifying the mathematical model of the hysteresis model for a steering system and adding custom parameters, the availability of adjusting the shape of steering feel model for various physical and dynamic conditions increases. Addition of a term about the tire dynamics to the steering feel model renders the steering wheel torque feedback more informative about the tire road interaction. Some simulation results are presented to establish the feasibility of the proposed model. The results of hardware-in-the-loop simulations show that the model provides a realistic and informative steering feel.

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Research on Torque Ratio Based on the Steering Wheel Torque Characteristic for Steer-by-Wire System

Journal of Applied Mathematics ◽

10.1155/2014/929164 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7

Author(s):

Yandong Han ◽

Lei He ◽

Xiang Wang ◽

Changfu Zong

Keyword(s):

Force Feedback ◽

Characteristic Curve ◽

Transmission Ratio ◽

Steering Wheel ◽

Vehicle Handling ◽

Design Goal ◽

Torque Transmission ◽

Steer By Wire ◽

Wheel Torque ◽

Wire System

Steer-by-wire system can improve the performance of vehicle handling stability. Removing the mechanical linkages between the front wheels and the steering wheel leads to a key technique of force feedback for steer-by-wire system. In view of the characteristic of variable torque transmission ratio for steer-by-wire system, this paper proposes a method for designing torque ratio based on the steering wheel torque characteristic for steer-by-wire system. It converts the torque ratio design into equivalent assist torque design by analyzing their relationship. It achieves the torque ratio design at different conditions based on the negative equivalent assist torque characteristic curve. Simulations and vehicle experiments are conducted by the proposed method, and the results show that the design goal has been achieved and the steering wheel torque characteristic obtained is very similar to that of the reference car.

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Methods for modeling the steering wheel torque of a steer-by-wire vehicle

Automotive and Engine Technology ◽

10.1007/s41104-021-00093-2 ◽

2021 ◽

Author(s):

Felix Heinrich ◽

Jonas Kaste ◽

Sevsel Gamze Kabil ◽

Michael Sanne ◽

Ferit Küçükay ◽

...

Keyword(s):

Steering Wheel ◽

Modular Approach ◽

Haptic Information ◽

Mathematical Functions ◽

Mechanical Coupling ◽

Steering Feel ◽

Input Signals ◽

Steer By Wire ◽

Wheel Torque ◽

Best Fit

AbstractUnlike electromechanical steering systems, steer-by-wire systems do not have a mechanical coupling between the wheels and the steering wheel. Therefore, a synthetic steering feel has to be generated to supply the driver with the necessary haptic information. In this paper, the authors analyze two approaches of creating a realistic steering feel. One is a modular approach that uses several measured and estimated input signals to model a steering wheel torque via mathematical functions. The other approach is based on an artificial neural network. It depends on steering and vehicle measurements. Both concepts are optimized and trained, respectively, to best fit a reference steering feel obtained from vehicle measurements. To carry out the analysis, the two approaches are evaluated using a simulation model consisting of a vehicle, a rack actuator, and a steering wheel actuator. The research shows that both concepts are able to adequately model a desired steering feel.

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Development of Estimation Force Feedback Torque Control Algorithm for Driver Steering Feel in Vehicle Steer by Wire System: Hardware in the Loop

International Journal of Vehicular Technology ◽

10.1155/2015/314597 ◽

2015 ◽

Vol 2015 ◽

pp. 1-17 ◽

Cited By ~ 13

Author(s):

Sheikh Muhammad Hafiz Fahami ◽

Hairi Zamzuri ◽

Saiful Amri Mazlan

Keyword(s):

Control Algorithm ◽

Force Feedback ◽

Steering System ◽

Front Axle ◽

Torque Control ◽

Steering Wheel ◽

Hardware In The Loop ◽

Linear Quadratic ◽

Steering Feel ◽

Steer By Wire

In conventional steering system, a feedback torque is produced from the contact between tire and road surface and its flows through mechanical column shaft directly to driver. This allows the driver to sense the steering feel during driving. However, in steer by wire (SBW) system, the elimination of the mechanical column shaft requires the system to generate the feedback torque which should produce similar performance with conventional steering system. Therefore, this paper proposes a control algorithm to create the force feedback torque for SBW system. The direct current measurement approach is used to estimate torque at the steering wheel and front axle motor as elements to the feedback torque, while, adding the compensation torque for a realistic feedback torque. The gain scheduling with a linear quadratic regulator controller is used to control the feedback torque and to vary a steering feel gain. To investigate the effectiveness of the proposed algorithm, a real-time hardware in the loop (HIL) methodology is developed using Matlab XPC target toolbox. The results show that the proposed algorithm is able to generate the feedback torque similar to EPS steering system. Furthermore, the compensation torque is able to improve the steering feel and stabilize the system.

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Road Feel Design for Vehicle Steer-by-Wire System Based on Joystick

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.336-338.734 ◽

2013 ◽

Vol 336-338 ◽

pp. 734-737

Author(s):

Hong Yu Zheng ◽

Ya Ning Han ◽

Chang Fu Zong

Keyword(s):

Computer Simulation ◽

Control Strategy ◽

Vehicle Speed ◽

Control Module ◽

Matlab Simulink ◽

The Road ◽

Steering Feel ◽

Steer By Wire ◽

Simulation Results ◽

Wire System

In order to solve the problem of road feel feedback of vehicle steer-by-wire (SBW) system based on joystick, a road feel control strategy was established to analyze the road feel theory of traditional steer system, which included return, assist and damp control module. By verifying the computer simulation results with the control strategy from software of CarSim and Matlab/Simulink, it shows that the proposed strategy can effective get road feel in different vehicle speed conditions and could improve the vehicle maneuverability to achieve desired steering feel by different drivers.

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