Multi-Stage Piezo-Diaphragm Sensor for Wideband Sound and Vibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing piezo-diaphragm sensors have limited signal bandwidth and sensitivity, particularly in the high-frequency range, making them inadequate for applications requiring wideband audio sensing and environmental robustness, such as automotive voice detection and noise cancellation systems.
Innovation Solution
A multi-stage sound and vibration sensor design incorporating a first and second piezo-diaphragm with a flexible bottom surface that generates a second resonance frequency, forming a two-degree-of-freedom system to extend the signal bandwidth and enhance sensitivity, especially at high frequencies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a single piezo-diaphragm is used, then the device complexity is low, but the signal bandwidth and sensitivity are limited
Solution Approach 1:
The sensor is divided into multiple stages with separate piezo-diaphragms, each contributing to different frequency ranges. This segmentation allows the system to achieve wideband performance by combining the outputs of individual elements, resolving the contradiction between limited bandwidth and device complexity.
Solution Approach 2:
The patent transitions from a single-degree-of-freedom system to a two-degree-of-freedom system by adding a second piezo-diaphragm stage. This dimensional change in the system's mechanical degrees of freedom enables extended frequency response while maintaining a structured, manageable design.
2Measurement precision
If a single piezo-diaphragm is used, then the device structure is simple, but the high-frequency sensitivity is insufficient
Solution Approach 1:
The frequency detection range is segmented between two piezo-diaphragm stages, with each stage optimized for specific frequency ranges. This segmentation enables high-frequency sensitivity enhancement without requiring a completely complex device structure, as each stage remains relatively simple.
Solution Approach 2:
The patent utilizes mechanical vibration principles by designing the second piezo-diaphragm stage to resonate at higher frequencies, thereby enhancing high-frequency sensitivity. This approach improves measurement precision in the high-frequency range while maintaining a structured device design based on established vibration theory.
3Reliability
If environmental robustness is enhanced for automotive applications, then the reliability improves, but the device complexity increases
Solution Approach 1:
The multi-stage sensor design serves multiple functions simultaneously: it provides wideband audio sensing, vibration detection, and environmental robustness for automotive applications. By integrating these functions into a single device architecture, the patent achieves improved reliability without proportionally increasing complexity.
Solution Approach 2:
The sensor incorporates dynamic elements including flexible diaphragms and vibration-based detection mechanisms that adapt to different environmental conditions. This dynamic design enhances environmental robustness while maintaining a manageable device complexity through efficient use of mechanical principles.
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 sensor achieves improved signal bandwidth and sensitivity across a wider frequency range, enabling effective voice detection and noise cancellation by maintaining flat frequency response and enhancing environmental robustness.
Implementation Method 1
Due to the piezoelectric effect presented by the piezoelectric ceramic disk that converts electrical signals (e.g., voltage, charge) into mechanical signals (e.g., deformation, strain, etc.) and vice versa
Implementation Method 2
The first piezo-diaphragm and the second piezo-diaphragm provide a first resonance frequency and a second resonance frequency in response to detecting the audio or the vibrations
Data Source
AI summary
In at least one embodiment, a multi-stage sound and vibration sensor is provided. The multi-stage sound and vibration sensor includes a housing, a first piezo-diaphragm and a second piezo diaphragm. The first piezo-diaphragm and the second piezo-diaphragm are positioned in the housing to detect an input signal including audio or vibrations. The first piezo-diaphragm and the second piezo-diaphragm provide a first resonance frequency and a second resonance frequency in response to detecting the audio or the vibrations.