Vehicle Door Handle Inductive Sensing With Lever-Arm Target Motion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing capacitive sensor-based systems for detecting user intention to lock or unlock vehicle doors are prone to false detections due to environmental conditions like humidity, salt, rain, and metallic coatings, which hinder reliable detection.
Innovation Solution
A device using an inductive sensor with an amagnetic metal target and a flexible lever arm support element, where the target is positioned at the free end of the lever arm, allowing for increased movement and detection amplitude when a user presses the handle, combined with capacitive sensing for enhanced reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If capacitive sensors are used for detecting user presence, then the detection device can be integrated into the handle structure, but false detections occur due to environmental conditions like humidity, salt, and metallic coatings
Solution Approach 1:
The patent replaces capacitive sensing with inductive sensing using a primary coil and amagnetic metal target. The inductive sensor detects target position through electromagnetic coupling rather than capacitive coupling, making it immune to environmental factors like humidity, salt, and metallic coatings that cause false detections in capacitive systems.
Solution Approach 2:
The patent changes the detection parameter from capacitive coupling to inductive coupling. By using electromagnetic fields instead of electric fields, the system achieves reliable detection in challenging environmental conditions where capacitive sensors fail.
2Volume of moving object
If the target is positioned close to the coil for compact design, then device size is reduced, but detection amplitude decreases
Solution Approach 1:
The patent introduces a flexible lever arm that allows dynamic positioning of the amagnetic metal target. The lever arm enables the target to move through a larger range relative to the primary coil during handle actuation, increasing detection amplitude while maintaining a compact overall device structure.
Solution Approach 2:
The patent uses a lever arm mechanism that transforms linear handle movement into amplified angular motion of the target relative to the coil. This mechanical advantage in another dimension (rotational movement) increases the effective detection amplitude without increasing the linear footprint of the device.
3Stability of the object's composition
If a rigid support structure is used for the target, then structural stability is improved, but detection sensitivity decreases
Solution Approach 1:
The patent replaces rigid support with a flexible lever arm that provides the necessary compliance for sensitive detection. The flexible support allows the target to respond to subtle handle movements while maintaining sufficient structural integrity through its elastic properties.
Solution Approach 2:
The patent employs a flexible lever arm made of elastomeric material to support the amagnetic metal target. This flexible support structure enables high detection sensitivity by allowing the target to move freely in response to handle actuation, while still providing adequate mechanical support.
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
The solution significantly improves detection reliability by amplifying the target's movement and reducing false positives, even in challenging environmental conditions, while maintaining compatibility with metallic handles.
Implementation Method 1
A device for detecting the intention of a user to lock or unlock an opening element (1) of a motor vehicle by induction
Implementation Method 2
a housing containing a support element, a variation in the position of which along a predetermined axis (A) occurs under pressure from a hand (3) of the user
Data Source
AI summary
The invention relates to a device for detecting the intention to unlock an opening element (1) of a motor vehicle with a housing (4) containing a support element (12) having a region of contact (11) with a handle (2) and being associated with an amagnetic metal target (6), the device comprising a printed circuit board (9), a voltage source and at least one emitter primary coil (7). The support element (12) forms an elongated lever arm, the target (6) being arranged at its longitudinal free end with its other longitudinal end fixed to an anchoring point (14) on the housing (4) while being flexible toward the primary coil (7) under the action of the pressure from the user on the opening element handle (2) or frame which is transmitted to the contact region (11) located away from the target (6) by more than half of a length of the support element (12).