Steering Wheel HOD Conductive Region Grounding
Solution Overview
Problem
Conventional Hand Off Detection (HOD) devices face challenges in accommodating different steering wheel sizes and structures, and capacitance sensing is often interfered by unstable factors such as footwear and floor mats due to long sensing paths that include the user's body.
Innovation Solution
The integration of conductive regions within or on the covering material of the steering wheel, coupled to a capacitance detection circuit or a vehicle's ground source, provides a short capacitance sensing path, reducing interference from external factors and allowing for adaptable design configurations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional sensing lines are used that pass through the user's body from hand to feet, then the HOD function can be implemented, but the capacitance sensing path becomes long and is interfered by unstable factors such as footwear and floor mats
Solution Approach 1:
The patent extracts the sensing path from the user's body by introducing conductive regions directly into the steering wheel covering material. This removes the problematic portion of the sensing path that passes through the user's body, footwear, and floor mat, thereby eliminating the source of instability and interference while maintaining the HOD function.
Solution Approach 2:
The patent introduces conductive regions as intermediary elements within the steering wheel structure. These conductive regions serve as mediators that establish a direct capacitance sensing path between the user's hand and the detection circuit, bypassing the unstable external factors (footwear and floor mat) that previously interfered with the sensing process.
2Adaptability or versatility
If steering wheels are designed for different brands with different sizes and structures, then various design requirements can be met, but it becomes hard to design a general purpose HOD device
Solution Approach 1:
The patent creates a universal HOD solution by integrating conductive regions directly into the covering material of the steering wheel. This approach allows the same basic structure to be adapted to different steering wheel sizes and configurations without requiring separate sensing line routing designs, making the system universally applicable across different vehicle brands and models.
Solution Approach 2:
The patent segments the sensing function into discrete conductive regions that can be independently positioned and configured within the covering material. This segmentation allows flexible adaptation to different steering wheel geometries while maintaining a consistent implementation approach, reducing design complexity across various applications.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enhances the reliability of HOD systems by minimizing interference from unstable factors and enabling compatibility with various steering wheel designs through a short capacitance sensing path, improving the accuracy of driver engagement detection.
Implementation Method 1
the conductive region is coupled to a capacitance detection circuit or a ground source of the vehicle
Data Source
AI summary
An HOD device, comprising: a framework; covering material, covering the frame work; at least one conductive region, provided on or in the covering material; wherein the conductive region is coupled to a capacitance detection circuit or a predetermined voltage level. The HOD device can be a vehicle control device such as a steering wheel. The conductive region comprises conductive wires which can be threads of the covering material. By this way, the arrangements of the conductive wires can be changed corresponding to the size or the shape of the frame work or any other requirements. Also, the interference caused by unstable factors can be improved since the conductive wires can be coupled to a ground source of the vehicle to provide a short capacitance sensing path.