Mutual-Capacitance Proximity Sensing for Human vs Water Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional capacitance detection methods in wearable devices are prone to misjudgment when detecting human body approach due to interference from non-human bodies like water or sweat, leading to inaccurate user experience.
Innovation Solution
The proposed approaching detection apparatus utilizes a configuration where the first and second electrodes are arranged to ensure opposite directions of mutual capacitance value variations when a human body and a non-human body approach, allowing for improved distinction and accuracy in detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional capacitance detection method is used, then detection function is implemented, but misjudgment occurs when non-human body (water, sweat) approaches
Solution Approach 1:
The detection system is divided into multiple independent detection dimensions: self-capacitance detection (first detection dimension) and mutual capacitance detection (second detection dimension). Each dimension uses separate electrodes and detection circuits to measure different capacitance parameters, enabling comprehensive analysis to distinguish human body from non-human objects
Solution Approach 2:
A control circuit acts as an intermediary that receives detection signals from both self-capacitance and mutual capacitance detection paths, processes the signals according to a predetermined algorithm, and generates the final detection result. This intermediary processing enables differentiation between human body and non-human objects based on the combined detection data
2Measurement precision
If single capacitance detection electrode is used, then device structure is simple, but detection accuracy is insufficient to distinguish human body from non-human body
Solution Approach 1:
The detection system uses multiple electrodes that serve dual functions: the first electrode serves both as a self-capacitance detection electrode and as one plate of the mutual capacitance detection capacitor. The second electrode serves as the other plate of the mutual capacitance detector. This multi-functionality reduces the total number of electrodes needed while achieving accurate human body detection
Solution Approach 2:
The self-capacitance detection path and mutual capacitance detection path are merged into a single integrated detection system. The first electrode is shared between both detection paths, and the control circuit processes both detection signals to generate a unified detection result, thereby reducing device complexity while improving detection accuracy
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 effectively reduces the misjudgment rate by ensuring that the variations in mutual capacitance due to human and non-human body approaches are oppositely directed, facilitating accurate detection and enhancing user experience.
Implementation Method 1
a first electrode 21, a second electrode 22, and a detection module 211. The detection module 211 is configured to detect a variation of a mutual capacitance value between the first electrode 21 and the second electrode 22
Data Source
Figure 1~3
Figure 4~6
Figure 7~9
AI summary
An approaching detection apparatus and an electronic device are provided, which are beneficial to improving the distinction between a human body approaching the device and a non-human body approaching the device. The apparatus for use in the electronic device includes: a first electrode, a second electrode, and a detection module configured to detect a variation of a mutual capacitance value between the first electrode and the second electrode, the detection module being electrically connected to the first electrode and the second electrode, the variation of the mutual capacitance value being used to determine an approaching state of the electronic device, wherein, when a human body approaches the electronic device, the variation of the mutual capacitance value is a first variation, and when a non-human body approaches the electronic device, the variation of the mutual capacitance value is a second variation, one of the first variation and the second variation being a positive value and the other of the first variation and the second variation being a negative value.