Steering Control Device Torque Neutral Position Offset
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Solution Overview
Problem
Conventional steering systems cause a large steering load on drivers when correcting the vehicle's position within a lane due to the coincidence of steering angle and torque neutral positions, leading to inverted steering torque signs.
Innovation Solution
A steering control device that mechanically uncouples the steering unit from the turning unit, with a steering reaction force characteristic that increases with self-aligning torque, offsetting the steering torque neutral position to reduce the likelihood of steering torque sign inversion during corrective steering.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the steering angle neutral position and steering torque neutral position coincide with each other, then the steering system structure is simple, but the steering load on the driver increases during corrective steering
Solution Approach 1:
The patent offsets the steering torque neutral position relative to the steering angle neutral position by adjusting the steering reaction force characteristic coordinates. This parameter change allows the steering torque to maintain the same sign during corrective steering operations, preventing the driver from experiencing sudden force direction changes and reducing overall steering load.
2Ease of operation
If the steering reaction force characteristic is offset to increase absolute value closer to white line, then the steering torque neutral position is offset to reduce sign inversion, but the steering system complexity increases
Solution Approach 1:
The patent implements dynamic offset of the steering reaction force characteristic based on real-time lateral position detection. The steering torque neutral position is dynamically adjusted relative to the steering angle neutral position according to the vehicle's lateral distance from the lane center, enabling adaptive reduction of steering torque sign inversion during corrective steering.
Solution Approach 2:
The patent uses lateral position detection feedback to continuously adjust the steering reaction force characteristic offset. The controller monitors the vehicle's lateral position relative to the lane and dynamically modifies the steering torque neutral position to prevent sign inversion, creating a closed-loop control system that reduces steering load.
Data Source
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AI summary
The turning amount of a turning unit (2) is controlled according to the steering amount of a steering unit (1) mechanically uncoupled from the turning unit (2). A steering reaction force characteristic in which the larger the self-aligning torque, the larger the steering reaction force is set on coordinates with the self-aligning torque and the steering reaction force as coordinate axes. When the steering reaction force corresponding to the self-aligning torque is applied to the steering unit (1) based on the steering reaction force characteristic, the steering reaction force characteristic is offset on the coordinates in such a direction that the closer the lateral position of an own vehicle to a white line, the larger the absolute value of the steering reaction force.