Electric Power Steering Yaw Control Without Excessive Braking

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current ESC systems employ large braking operations on severe road surfaces, leading to reduced tire life.

Innovation Solution

A control method and apparatus for an electric power steering system that adjusts steering torque based on front steering angle, steering torque, yaw rate, and vehicle speed to enhance vehicle handling, avoiding excessive braking and tire wear.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the ESC system employs larger braking operations to reduce vehicle speed on severe road surfaces, then the vehicle can maintain stability and prevent skidding, but the tire life is reduced

Engineering Contradiction:
Improvevehicle stabilityVSAvoidtire life
Core Design Contradiction:
ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The patent merges the electric power steering system with the electronic stability control system by sharing the yaw rate sensor and integrating control logic. The EPS system receives yaw rate feedback and adjusts steering torque accordingly, combining steering control and stability control functions into a unified system that reduces redundant braking operations and extends tire life while maintaining vehicle stability.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent implements feedback control by using yaw rate sensor data to continuously monitor vehicle rotation and adjust steering torque in real-time. The control algorithm compares actual yaw rate with target yaw rate and modifies steering assistance accordingly, enabling precise control that reduces excessive braking and extends tire life while maintaining stability.

Inventive Principle:
Principle #23Feedback

2Reliability

If the ESC system uses braking operations to control vehicle speed on severe road surfaces, then the vehicle can maintain traction and prevent skidding, but the overall vehicle handling characteristic is degraded

Engineering Contradiction:
Improvetraction controlVSAvoidvehicle handling characteristic
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The patent replaces mechanical braking-based speed control with electric steering torque control. By using the electric power steering motor to adjust steering assistance based on yaw rate feedback, the system achieves speed control and traction maintenance through steering manipulation rather than braking, thereby preserving vehicle handling characteristics while maintaining traction on severe road surfaces.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentEP4144617B1Control method and apparatus
Publication Date: 2026.04.15 GREAT WALL MOTOR CO LTD
  • EP4144617B1 patent drawingFigure 1~2
  • EP4144617B1 patent drawingFigure 3~4
  • EP4144617B1 patent drawingFigure 5

AI summary

A control method and apparatus, which are applied to a vehicle with an electric power steering system. The electric power steering system comprises a first control subsystem and a second control subsystem. The method comprises: acquiring a front steering angle, a steering torque, a yaw rate and a vehicle speed of a vehicle; according to the front steering angle, the steering torque, the yaw rate and the vehicle speed, determining a vehicle yaw rate associated with a first control subsystem; determining, on the basis of the vehicle yaw rate, an expected deviation value associated with a second control subsystem; and determining a control parameter on the basis of the expected deviation value, such that the vehicle adjusts, according to the control parameter, the steering torque to run. According to the method, a vehicle can be controlled to adjust a steering torque according to a control parameter, thereby enhancing the overall vehicle handling characteristic of the vehicle, avoiding using a relatively large braking operation to greatly reduce the speed of the vehicle, and avoiding the situation of shortening the service life of tires.