Capacitive Sensor Ground Mass Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Proximity sensor devices face issues with signal artifacts and parasitic capacitance due to low ground mass conditions, which affect the accuracy of input detection in electronic systems.
Innovation Solution
A processing system with a sensor module and determination module that acquires measurements of capacitive coupling between sensor electrodes and an input object, using a low ground mass parameter to determine positional information, thereby mitigating the effects of low ground mass conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If transcapacitance sensing is used to detect input objects, then input detection capability is improved, but parasitic capacitance effects cause signal artifacts under low ground mass conditions
Solution Approach 1:
The patent introduces a ground mass compensation mechanism that acts as an intermediary to counteract parasitic capacitance effects. By measuring ground mass conditions and applying compensation algorithms, the system mediates between the transcapacitance sensing signals and the harmful parasitic effects, thereby maintaining measurement precision under low ground mass conditions
Solution Approach 2:
The patent dynamically adjusts sensing parameters based on detected ground mass conditions. When low ground mass is detected, the system modifies sensing parameters such as integration time, gain, or threshold values to compensate for parasitic capacitance effects, thereby maintaining accurate input detection across varying ground mass conditions
2Stability of the object's composition
If the input device is placed on a surface (low ground mass condition), then device stability is improved, but signal artifacts and detection accuracy deteriorate
Solution Approach 1:
The patent implements a feedback mechanism that continuously monitors ground mass conditions and adjusts sensing operations accordingly. The system measures ground mass, detects when it falls below a threshold indicating low ground mass conditions, and automatically applies compensation measures, creating a closed-loop feedback system that maintains signal accuracy regardless of device placement stability
Solution Approach 2:
The patent makes the sensing system dynamic by adapting its operation based on real-time ground mass conditions. Rather than using fixed sensing parameters, the system dynamically adjusts its behavior - switching between different sensing modes or applying different compensation algorithms - to maintain measurement precision whether the device is held or placed on a surface
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
Improves the accuracy of input detection by effectively addressing low ground mass conditions, ensuring reliable operation of proximity sensor devices in various environments.
Implementation Method 1
acquire a first plurality of measurements of change in capacitive coupling between each sensor electrode of a first set of sensor electrodes and a second set of sensor electrodes. The sensor module is further configured to acquire a second plurality of measurements of change in capacitive coupling between each sensor electrode of the second set of sensor electrodes and an input object
Implementation Method 2
when the grounding condition of the input device is low or otherwise non-optimal (e.g., when the input device is lying on a desk, rather than being held by a user), certain parasitic capacitance effects may result in signal artifacts and/or produce other deleterious results
Data Source
AI summary
A processing system for an input device includes a sensor module and a determination module. The sensor module includes sensor circuitry and is configured to acquire a first plurality of measurements of change in capacitive coupling between each sensor electrode of a first set of sensor electrodes and a second set of sensor electrodes. The sensor module is further configured to acquire a second plurality of measurements of change in capacitive coupling between each sensor electrode of the second set of sensor electrodes and an input object. The determination module is configured to determine a first combined measurement based on the first plurality of measurements, determine a second combined measurement based on the second plurality of measurements, and determine positional information for the input object based on a low ground mass parameter. The low ground mass parameter is based on the first combined measurement and the second combined measurement.