Stretchable Pressure Sensor With Meandering Interconnects
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional pressure sensors lack stretchability due to their rigid configurations, which restricts their ability to accommodate applied forces in multiple directions effectively.
Innovation Solution
A stretchable flexible pressure sensor design featuring meandering conductive interconnects on an elastic substrate, allowing for stretching and returning to the original shape, with optional foam or air gaps to facilitate movement and maintain conductivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional pressure sensors use rigid configurations with straight wires and pads, then manufacturing and structural simplicity is maintained, but stretchability and ability to accommodate applied forces in multiple directions is lost
Solution Approach 1:
The conductive interconnects are designed with meandering or serpentine curved paths instead of straight lines. This curvature allows the interconnects to flex and deform elastically when the substrate is stretched, accommodating the deformation while maintaining electrical connectivity. The curved geometry transforms the rigid straight wire configuration into a flexible meandering structure that can bend without breaking.
Solution Approach 2:
The patent employs a flexible substrate that can be stretched and deformed, and the conductive interconnects are designed as thin, flexible traces rather than rigid wires. This flexible film approach allows the entire sensor structure to adapt to stretching forces while maintaining its functional integrity, enabling the sensor to be conformable and stretchable.
2Reliability
If rigid conductive interconnects are used in pressure sensors, then ease of manufacture is maintained, but durability under repeated stretching and metal fatigue resistance deteriorates
Solution Approach 1:
The meandering curved design of conductive interconnects distributes mechanical stress along the curved path during stretching, preventing stress concentration at straight-line connections. This curvature allows the interconnects to flex repeatedly without developing fatigue cracks, significantly improving durability and resistance to metal fatigue while maintaining manufacturability through standard flexible PCB or printed circuit techniques.
3Adaptability or versatility
If the elastic substrate is stretched, then stretchability and adaptability are improved, but maintaining continuous electrical conductivity through the interconnects becomes difficult
Solution Approach 1:
The meandering curved geometry of the conductive interconnects allows them to flex and deform elastically when the substrate is stretched. The curved paths can bend and expand while maintaining continuous electrical contact, preventing wire breakage or connection failure that would occur with rigid straight wires. This curvature design ensures electrical conductivity is maintained throughout the stretching and relaxation cycles.
4Adaptability or versatility
If foam or air gaps are introduced to enable interconnect movement, then stretchability and pressure sensing capability are improved, but device complexity and manufacturing difficulty increase
Solution Approach 1:
The patent incorporates foam material within the elastic substrate at the sensing area. This porous foam structure allows the conductive interconnects to move and deform more freely when pressure is applied or when the substrate is stretched. The foam acts as a compliant support that accommodates interconnect movement while maintaining structural integrity, enabling improved pressure sensing capability without significantly complicating the overall device architecture.
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 accurate pressure measurement across various directions while maintaining durability and minimizing metal fatigue through the use of elastic substrates and meandering conductive paths.
Implementation Method 1
The elastic substrate comprises a material that enables the elastic substrate to be stretched in one or more directions
Implementation Method 2
Once released, the elastic substrate returns from the stretched position to the relaxed, non-stretched position, and slack is reintroduced into the stretchable conductive interconnects in the form of the original meandering shape
Implementation Method 3
the elastic substrate at each sensing area is replaced with a foam or air gap to enable movement of a top stretchable conductive interconnect, a bottom stretchable conductive interconnect or both toward each other in response to an applied force
Data Source
AI summary
A stretchable flexible pressure sensor includes stretchable conductive interconnects, or electrodes, sandwiching an elastic substrate that is stretchable in one or more directions. The interconnects are positioned on opposing surfaces of the elastic substrate and overlap at select sensing areas. The elastic substrate at each sensing area is replaced with a foam or air gap to enable movement of a top stretchable conductive interconnect, a bottom stretchable conductive interconnect or both toward each other in response to an applied force. The stretchable conductive interconnects are each patterned having a meandering shape and are aligned with each other. The meandering shape provides slack such that as the elastic substrate is stretched the slack is taken up.