Fiber-Based Strain Sensor with Negative Gauge Factor
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wearable devices, such as smart clothing, face limitations in power consumption and flexibility, restricting their ability to monitor biometric data effectively across various body parts without causing discomfort, and existing flexible displays suffer from image distortion when stretched due to increased pixel intervals.
Innovation Solution
A fiber-based strain sensor with a negative gauge-factor is developed, utilizing twisted conductive fibers with metal nano particles and insulating thin films to lower resistance only upon stretching, enabling low-power biometric signal transmission and preventing image distortion in stretchable displays.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional conductive fibers are used in wearable devices, then the device can maintain electrical conductivity, but the resistance increases upon stretching causing image distortion and limiting flexibility
Solution Approach 1:
The patent inverts the conventional behavior of conductive fibers by creating a structure where resistance decreases rather than increases upon stretching. The insulating layer is positioned between conductive fibers such that stretching brings fibers closer together, reducing the insulating barrier and lowering resistance, thereby enabling low-power operation while maintaining flexibility and image quality stability.
2Adaptability or versatility
If wearable devices are designed with high elasticity to monitor various body parts, then adaptability improves, but power consumption increases due to continuous monitoring requirements
Solution Approach 1:
The patent enables periodic action by allowing the conductive fiber to change its electrical state only when stretching occurs. The insulating layer blocks current flow during normal conditions, and current is activated only when stretching happens, creating a periodic on/off state that reduces power consumption while maintaining body part monitoring capability.
Solution Approach 2:
The conductive fiber structure serves itself by using the mechanical action of stretching to automatically activate current flow. The insulating layer and conductive fiber arrangement create a self-regulating system where the act of stretching itself provides the activation signal, eliminating the need for external power control mechanisms and reducing overall power consumption.
3Adaptability or versatility
If conductive fibers are made more flexible to enable stretching, then adaptability improves, but manufacturing precision becomes more difficult to control
Solution Approach 1:
The patent applies parameter changes by carefully controlling the thickness and material properties of the insulating layer to optimize the balance between flexibility and resistance control. By adjusting the insulating layer's parameters (thickness, material composition), the patent achieves the desired stretchability while maintaining manufacturable resistance characteristics.
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 solution minimizes power consumption, allows for flexible biometric monitoring across the body, and maintains image quality in stretchable displays by ensuring current flow only when stretched, thus addressing the limitations of existing wearable technologies.
Implementation Method 1
the insulating thin film is cured by selective irradiation of ultraviolet ray or laser
Implementation Method 2
a conductive part having the electric conductivity is formed by depositing metal nano particles in the first flexible part or the second flexible part
Data Source
AI summary
The present exemplary embodiments propose a fiber-based strain sensor including: at least one first electric conductive line including a first flexible part having electric conductivity and at least one second electric conductive line which is woven to be in partially contact with the first electric conductive line, includes a second flexible part having electric conductivity, and is implemented to conduct electricity with the first flexible part having electric conductivity in a stretched state.