Capacitive Positioning Device with Spacer and Reference Capacitance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Capacitive detectors for locating objects within mediums, such as walls, require manual calibration to account for ambient conditions and material properties, which complicates their operation and reduces measurement accuracy.
Innovation Solution
A capacitive locating appliance with a measurement electrode, a reception electrode, and a reference capacitance, arranged in a plane with a spacer to maintain a predetermined distance from the medium, uses an evaluation circuit to provide an output signal based on the ratio between measurement and reference capacitances, minimizing the influence of environmental and material properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If capacitive detectors are used to sense objects in walls, then detection capability is provided, but manual calibration is required due to ambient conditions and material properties
Solution Approach 1:
The detector performs self-calibration by automatically determining the dielectric properties of the wall material through capacitive measurements at different frequencies, eliminating the need for manual calibration by users
Solution Approach 2:
The system changes measurement parameters by using multiple frequencies to probe the wall material, allowing automatic determination of dielectric properties and compensation for environmental variations
2Measurement precision
If capacitive detectors are used to sense objects in walls, then detection capability is provided, but detection accuracy is reduced due to ambient conditions and material properties
Solution Approach 1:
The system uses feedback by continuously measuring capacitive properties and automatically adjusting for ambient conditions and material variations, compensating for harmful influences through real-time data processing
Solution Approach 2:
By measuring at different frequencies, the system changes parameters to distinguish between object signals and background interference from ambient conditions and wall materials
3Measurement precision
If multiple electrodes are used to detect capacitance changes, then detection capability is improved, but device complexity increases
Solution Approach 1:
The same electrode serves multiple functions by acting as both measurement electrode and reference electrode at different times, eliminating the need for separate reference electrodes and reducing overall device complexity
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 configuration allows the appliance to operate independently of minor changes in distance and material properties, providing a robust and accurate detection of objects without the need for manual calibration, ensuring consistent performance across varying conditions.
Implementation Method 1
the measurement electrode forms, with the reception electrode, a measurement capacitance that can be influenced by the object
Implementation Method 2
a spacer is provided in order to hold the electrodes at a predetermined minimum distance, other than zero, from the surface of the medium
Implementation Method 3
the locating appliance comprises an evaluation circuit for providing an output signal on the basis of a ratio between the measurement capacitance and the reference capacitance
Data Source
AI summary
A positioning device for capacitively detecting an object enclosed in a medium includes a measuring electrode, a receiving electrode, and a reference capacitance. The measuring electrode and the receiving electrode form a measuring capacitance that can be influenced by the object and the reference capacitance cannot be influenced by the object. The electrodes are disposed in a plane, and the device includes a spacer that is configured to keep the electrodes at a predetermined minimum distance from the surface of the medium. The predetermined minimum distance is different from zero.