Steer-By-Wire ADAS Override Using Torque-Scaled Roadwheel Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing steer-by-wire systems in vehicles with advanced driver assistance systems (ADAS) experience sudden step changes in vehicle dynamics during transitions from ADAS control to manual driver control, leading to unintended overrides and delayed responses.
Innovation Solution
A system that scales RWA position control based on torsion bar torque to gradually transition from ADAS to manual control, using a scale value to smooth the override process and prevent sudden changes in vehicle steering effort.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If ADAS control is transitioned to manual driver control in steer-by-wire systems, then driver takeover is achieved, but sudden step changes in vehicle dynamics occur
Solution Approach 1:
The system dynamically adjusts the scale value based on real-time torque sensor readings, transitioning smoothly from ADAS control to manual control. The scale value varies continuously rather than abruptly, allowing the roadwheel actuator to respond gradually to driver input while maintaining vehicle dynamics stability throughout the transition process.
Solution Approach 2:
The patent changes the control parameter from a fixed ADAS override threshold to a dynamic scale value that is continuously adjusted based on torque sensor measurements. This parameter transformation allows the system to maintain stability by gradually shifting control authority from the actuator to the driver based on the applied torque magnitude.
2Measurement precision
If ADAS override is implemented using torque threshold, then driver input detection is achieved, but unintended overrides and delayed responses occur
Solution Approach 1:
The system implements continuous feedback by reading torque sensor values and using them to dynamically adjust the scale value. This feedback loop ensures that the override response is both accurate (detecting genuine driver input) and reliable (responding appropriately without unintended overrides or delays), as the scale value adapts in real-time to the actual torque applied by the driver.
Data Source
AI summary
A system for controlling a steering system of a vehicle includes sensors configured to sense a plurality of values corresponding to operation of the steering system and a steering system controller configured to receive the sensed plurality of values, the sensed plurality of values including a torque value, determine a scale value based on the torque value, the scale value varying based on changes in the torque value, and control a roadwheel position of the steering system based on the scale value.