Resonant Frequency Pressure Sensor Using Compressible Dielectric
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pressure sensors, such as those using radar technology, face challenges in effectively measuring pressure changes without active systems and fail to utilize dielectric changes to shift resonant frequencies effectively, as seen in prior art like U.S. Pat. No. 6,919,521 and US Published Patent Application No. 2004/0159158 A1.
Innovation Solution
A passive pressure sensor system using a compressible dielectric material or a movable magnetic body in proximity to an antenna member, which changes the effective dielectric constant or impedance, shifting the resonant frequency in response to pressure changes, allowing for pressure measurement through radar technology without onboard electronics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a passive pressure sensor system using compressible dielectric material is used, then cost and manufacturability are improved, but measurement precision may be worsened due to lack of active electronics
Solution Approach 1:
The patent replaces active electronic pressure sensing mechanisms with a passive electromagnetic resonance-based system. A compressible dielectric material (foam) is positioned adjacent to a microstrip antenna, and pressure changes compress the foam, altering the effective dielectric constant and shifting the antenna's resonant frequency. This mechanical-to-electromagnetic substitution eliminates complex electronics while enabling radar-based remote pressure measurement.
Solution Approach 2:
The patent utilizes changes in the dielectric properties of the foam material under pressure to modulate the resonant frequency of the antenna. As pressure compresses the foam, its dielectric constant changes, which directly shifts the resonant frequency detectable by radar systems. This parameter change provides a measurable signal for pressure detection without requiring active electronics in the sensor.
2Measurement precision
If dielectric material compression is used to shift resonant frequency, then pressure measurement capability is improved, but device complexity increases due to additional components
Solution Approach 1:
The patent combines the dielectric material (foam) directly with the antenna structure, eliminating the need for separate transduction mechanisms. The foam serves dual purposes: as a mechanical element that responds to pressure and as a dielectric that modulates the electromagnetic resonance. This merging reduces overall device complexity while maintaining pressure measurement functionality.
Solution Approach 2:
The antenna structure serves multiple functions: it acts as both the electromagnetic resonator for radar detection and the interface for dielectric coupling with the compressible foam. This multi-functionality reduces the number of separate components needed, simplifying the overall device structure while enabling pressure measurement through resonant frequency shifts.
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
Enables reliable, low-cost, and widely distributable pressure sensing capable of detecting pressure changes from a distance, suitable for various applications including military, commercial, medical, and automotive uses, with enhanced reliability and reduced manufacturing costs compared to traditional MEMs pressure sensors.
Implementation Method 1
The compression of the dielectric material changes the effective dielectric constant of the antenna
Implementation Method 2
an antenna member that is adapted to be resonantly responsive to a desired frequency of electromagnetic radiation
Implementation Method 3
A magnetic body is positioned in proximity to the antenna member and is movable along an essentially perpendicular axis to the antenna member
Implementation Method 4
Radar systems and the like use the reflective properties of objects to gather information from a distance
Data Source
AI summary
A pressure sensor (S) includes an antenna member (10) that is adapted to be resonantly responsive to a desired frequency of electromagnetic radiation (12). An inductance changing body formed from a compressible dielectric material (14) is positioned in proximity to the antenna member (10). A housing member (16) houses the antenna member (10) in a desired proximity to the compressible dielectric material (14). The compression of the dielectric material (14) changes the effective dielectric constant of the antenna (10).