Variable Angle-Ratio Steering Control for Emergency Avoidance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing steer-by-wire steering systems do not facilitate easy and quick emergency avoidance operations by the driver, as they require significant effort to maneuver the steering wheel during critical situations.
Innovation Solution
A steering control device that includes a target steering corresponding value computation unit, an emergency determination unit, and a work adjustment unit to reduce the operational effort required during emergency avoidance maneuvers by adjusting the steering system's response based on detected emergencies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a steer-by-wire steering system is used to separate the power transmission path between the steering wheel and steered wheels, then the system can provide precise steering control and improve driver convenience, but the driver must exert significant effort to maneuver the steering wheel during emergency avoidance operations
Solution Approach 1:
The steering control device dynamically adjusts the angle ratio between the steering wheel and steered wheels based on detected emergency conditions. During normal operation, the system maintains standard steering characteristics. When an emergency is detected (through sensors detecting rapid steering input or collision risk), the system switches to emergency mode where the angle ratio is modified to provide larger steered wheel movement for a given steering wheel input, enabling quick avoidance maneuvers with reduced driver effort.
Solution Approach 2:
The system changes the steering parameter (angle ratio) from a fixed value to a variable value that adapts to different operating conditions. The control unit modifies the angle ratio parameter based on emergency detection, thereby changing the mechanical characteristic of the steering system to reduce the force and effort required during critical avoidance operations while maintaining normal steering precision during regular driving.
2Reliability
If the steering system maintains normal steering characteristics during all operations, then the system provides consistent steering feel, but the system does not facilitate quick and easy emergency avoidance operations
Solution Approach 1:
The system performs preliminary detection of emergency conditions through sensors that monitor steering wheel angle, angular velocity, and vehicle state. Before the actual emergency maneuver is fully initiated, the control unit already detects the emergency pattern and prepares to switch the angle ratio to emergency mode, ensuring that the steering system is ready to respond immediately when the driver needs emergency avoidance capability.
Solution Approach 2:
The steering control device continuously monitors steering wheel operations and vehicle state through feedback from various sensors. When the feedback indicates an emergency pattern (rapid steering input, high angular velocity, specific vehicle conditions), the system automatically adjusts the angle ratio to emergency mode, providing the necessary speed and ease for avoidance operations while returning to normal mode after the emergency condition resolves.
Data Source
AI summary
A steering control device includes an emergency determination unit configured to determine whether or not an emergency exists in which an emergency avoidance operation is to be performed, and a work adjustment unit configured to adjust work of a driver required to steer steered wheels. The work adjustment unit is configured to execute emergency adjustment processing for adjusting the work in accordance with a determination result of whether or not an emergency exists. The emergency adjustment processing includes reduction processing for reducing the work in an initial stage after the emergency determination unit determines that an emergency exists, as compared in a case in which determination is not made that an emergency exists.