EPS Yaw Rate Feedback Control to Reduce ESC Brake Overuse
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The current ESC system employs large braking operations on severe road surfaces, leading to reduced tire life.
Innovation Solution
A control method and apparatus for vehicles with an electric power steering system, utilizing a first and second control subsystem to determine a control parameter based on vehicle yaw rate, adjusting steering torque to enhance handling and avoid excessive braking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the ESC system employs larger braking operations to reduce vehicle speed on severe road surfaces, then the vehicle stability and safety are improved, but the tire life is reduced
Solution Approach 1:
The patent merges the electric power steering system with the electronic stability control system by sharing the yaw rate sensor and control processor. The EPS system receives yaw rate signals and vehicle speed signals to calculate expected yaw rate and deviation values, then generates steering torque adjustments that work in conjunction with ESC braking operations to maintain vehicle stability without relying solely on aggressive braking
Solution Approach 2:
The patent implements a feedback mechanism where the control processor continuously monitors actual yaw rate from the yaw rate sensor and compares it with the expected yaw rate calculated from steering angle and vehicle speed. The deviation value is fed back to adjust the steering torque in real-time, allowing the system to adapt to severe road conditions dynamically and maintain stability while minimizing tire wear from excessive braking
2Reliability
If the ESC system uses larger braking operations to maintain vehicle control on wet or rough roads, then the vehicle safety is improved, but the steering torque adjustment capability is reduced
Solution Approach 1:
The patent combines the steering control functions of the electric power steering system with the stability control functions of the ESC system. The control processor integrates signals from both systems to generate coordinated control commands, allowing the steering system to respond to driver inputs while simultaneously executing stability corrections through torque adjustment rather than solely through braking
Solution Approach 2:
The patent introduces the control processor as an intermediary that receives yaw rate signals and vehicle speed signals, calculates the expected yaw rate and deviation values, and generates appropriate steering torque adjustments. This intermediary function allows the system to mediate between driver steering intentions and stability control requirements, providing smooth torque adjustments that maintain safety while preserving steering responsiveness
Data Source
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.