Steering Torque Thresholding for Accurate Driver Steering Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing steering determination systems inaccurately determine a driver's steering state due to influences from vehicle travel, as they rely solely on steering torque thresholds without considering longitudinal, lateral, and vertical accelerations, leading to erroneous steering state assessments.
Innovation Solution
A steering determination device that utilizes a torque recognition unit, acceleration recognition unit, and threshold value setting unit to adjust the steering torque threshold based on measured longitudinal, lateral, and vertical accelerations, ensuring accurate determination of the driver's steering state by differentiating between intentional and unintentional steering torques.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the steering state is determined based on a fixed steering torque threshold value, then the determination process is simple, but the determination accuracy deteriorates due to influences from vehicle travel such as longitudinal and lateral accelerations
Solution Approach 1:
The patent applies the dynamics principle by making the steering torque threshold value dynamic rather than fixed. The threshold value is adjusted in real-time based on detected vehicle acceleration (longitudinal, lateral, and vertical). When acceleration is detected, the threshold is increased to prevent false positive steering state determinations caused by acceleration-induced torque on the steering wheel. This dynamic adjustment resolves the contradiction by maintaining simple determination logic while improving accuracy through adaptive thresholding.
Solution Approach 2:
The patent applies parameter changes by modifying the steering torque threshold parameter based on acceleration conditions. The system changes the threshold parameter value according to the magnitude of detected acceleration, thereby adapting the determination criterion to current vehicle dynamics. This resolves the contradiction by allowing the system to maintain simple binary determination logic while improving accuracy through parameter adaptation to changing vehicle conditions.
2Reliability
If the steering torque threshold value is increased to avoid false positives during acceleration, then the false positive rate decreases, but the responsiveness to actual steering operations deteriorates
Solution Approach 1:
The system dynamically adjusts the threshold value based on real-time acceleration detection. During acceleration events, the threshold is temporarily increased to reduce false positives. During normal conditions with no significant acceleration, the threshold returns to a lower value that is sensitive to actual steering operations. This dynamic behavior resolves the contradiction by applying high thresholds only when necessary (during acceleration) and using low thresholds during normal operation, thereby maintaining both reliability and responsiveness.
Solution Approach 2:
The system periodically monitors acceleration and adjusts the threshold value accordingly. When acceleration exceeds a certain level, the threshold is increased for the duration of the acceleration event. This periodic adjustment based on acceleration cycles allows the system to maintain high reliability during acceleration while preserving responsiveness during normal driving conditions, resolving the contradiction between these two opposing requirements.
Data Source
AI summary
A steering determination device determines a steering state in which a driver of a vehicle is steering a steering wheel of the vehicle. The device includes a torque recognition unit configured to recognize a steering torque based on a measurement result of a torque sensor provided on a steering shaft, an acceleration recognition unit configured to recognize longitudinal acceleration or lateral acceleration, a threshold value setting unit configured to set a threshold value for the determination of the steering state, based on the longitudinal acceleration or the lateral acceleration, and a steering determination unit configured to determine that the driver is in the steering state if the steering torque is equal to or greater than the threshold value. The threshold value setting unit is configured to set the threshold value such that the threshold value decreases as an absolute value of the longitudinal acceleration or the lateral acceleration decreases.