KR-20260064515-A - ROLLING STRAIN SENSOR AND METHOD OF MANUFACTURING THE SAME

KR20260064515AKR 20260064515 AKR20260064515 AKR 20260064515AKR-20260064515-A

Abstract

A rolling strain sensor with a 3D structure and a method for manufacturing the same are disclosed. A rolling strain sensor with a 3D structure according to one embodiment of the present invention comprises: a flexible substrate in which a plurality of films having 2D electrode patterns are connected by tensile electrodes; and at least one elastomer sheet made of a material capable of tensiles, wherein the flexible substrate is joined to the at least one elastomer sheet in a 3D structure while being rolled, and when strain is applied from the outside, the capacitance changes as the overlapping area between the upper electrode and the lower electrode joined to the at least one elastomer sheet changes.

Inventors

김윤정
김혜진
서새롬

Assignees

한국전자통신연구원

Dates

Publication Date: 20260507
Application Date: 20251001
Priority Date: 20241031

Claims (14)

A flexible substrate having a plurality of films having 2D electrode patterns formed thereon connected by tensile electrodes; and At least one elastomer sheet made of a tensile material Includes, A 3D structure rolling strain sensor characterized in that the flexible substrate is bonded to the at least one elastomer sheet in a 3D structure while being rolled, and when strain is applied from the outside, the capacitance changes as the overlapping area between the upper electrode and the lower electrode bonded to the at least one elastomer sheet changes.
In claim 1, The above flexible substrate is A 3D structured rolling strain sensor characterized by being designed by considering a first parameter corresponding to the width, length, number of films, length excluding the overlapping area between films, and the tensile electrode angle.
In claim 2, The above at least one elastomer sheet is A 3D-structured rolling strain sensor characterized by being manufactured by considering a second parameter corresponding to a modulus, sheet thickness, number of sheets, and arrangement method for multiple sheets.
In claim 3, Strain stress based on the above first parameter and the above second parameter Or a 3D structured rolling strain sensor characterized by adjustable sensitivity to changes in capacitance.
In claim 4, A 3D-structured rolling strain sensor characterized in that the strain stress decreases as the tensile electrode angle decreases, and the strain stress increases as the tensile electrode angle increases.
In claim 4, A 3D-structured rolling strain sensor characterized by the fact that as the thickness of the sheet becomes thinner, the value of the initial capacitance decreases, while the sensitivity to changes in capacitance improves.
In claim 4, A 3D rolling strain sensor characterized in that, when the above-mentioned at least one elastomer sheet is composed of a plurality of sheets having different moduli, the strain stresses on opposing surfaces in the sensor are different.
A step of designing a flexible substrate by connecting a plurality of films having 2D electrode patterns formed thereon with a tensile electrode; A step of manufacturing at least one elastomer sheet from a tensile material; and A step of fabricating a rolling strain sensor with a 3D structure by rolling the flexible substrate onto at least one elastomer sheet. Includes, The above rolling strain sensor is A method for manufacturing a 3D-structured rolling strain sensor characterized by a change in capacitance as the overlapping area between the upper electrode and the lower electrode bonded to the at least one elastomer sheet changes when external strain is applied.
In claim 8, The step of designing the above flexible substrate is A method for manufacturing a rolling strain sensor with a 3D structure, characterized by designing the flexible substrate by considering a first parameter corresponding to the width, length, number of films, length excluding the overlapping area between films, and the tensile electrode angle.
In claim 9, The step of manufacturing at least one elastomer sheet above A method for manufacturing a rolling strain sensor with a 3D structure, characterized by manufacturing at least one elastomer sheet by considering a second parameter corresponding to a modulus, the thickness of the sheet, the number of sheets, and a method of arranging multiple sheets.
In claim 10, A method for manufacturing a 3D-structured rolling strain sensor characterized by adjusting the sensitivity to strain stress or capacitance change of the rolling strain sensor based on the first parameter and the second parameter.
In claim 11, The above rolling strain sensor is A method for manufacturing a rolling strain sensor of a 3D structure, characterized in that the strain stress decreases as the tensile electrode angle decreases, and the strain stress increases as the tensile electrode angle increases.
In claim 11, The above rolling strain sensor is A method for manufacturing a rolling strain sensor with a 3D structure, characterized in that the thinner the thickness of the sheet, the smaller the value of the initial capacitance, while the sensitivity to changes in capacitance is improved.
In claim 11, The above rolling strain sensor is A method for manufacturing a 3D-structured rolling strain sensor characterized in that, when the above-mentioned at least one elastomer sheet is composed of a plurality of sheets having different moduli, the strain stresses on opposing surfaces in the sensor are different.

Description

Rolling Strain Sensor and Method of Manufacturing the Same The present invention relates to a strain sensor with a 3D structure and a manufacturing technique thereof, and in particular, to a high-sensitivity strain sensor technique for measuring minute tensile changes in a flexible, stretchable area such as skin, by forming a 3D structure through a simple rolling process of wrapping a 2D electrode substrate in a flexible elastomer sheet. Strain sensors utilize the principle that resistance, capacitance, or electrical properties change in response to external mechanical strain, such as tension or compression, and are used in various fields including structural deformation monitoring, wearable devices, robotics, and medical devices. Various studies have been conducted to improve the sensitivity of these strain sensors, and among them, one method involves utilizing an origami structure as a process for changing dimensions (2D to 3D). Origami strain sensors are a technology inspired by the traditional Japanese art of paper folding that transforms 2D planar structures into 3D forms to realize various physical properties. These structures are utilized as sensors capable of detecting electrical signals through mechanical deformation and are being extensively researched in fields where sensitivity and flexibility are critical. Furthermore, these structural characteristics are advantageous for detecting mechanical deformation and allow for sensitive responses to tension and pressure in various directions. In other words, origami strain sensors can realize structurally complex forms and function as sensors sensitive to changes in electrical signals. However, conventional origami strain sensors require complex design and assembly processes to convert into a 3D structure. This process demands high precision, and even small errors or deformations occurring during manufacturing can degrade the sensor's signal reproducibility, making it difficult to guarantee reliability. Consequently, there are limitations to their application in fields requiring long-term monitoring or precise data collection. Furthermore, due to the complex folding process, they tend to become structurally bulky or significantly heavier, making them difficult to use in applications where miniaturization and lightweighting are essential, such as wearable devices, body-attached sensors, and small electronic devices. In particular, when portability and comfort must be considered, this increase in volume and weight poses practical limitations. FIGS. 1 to 3 are drawings illustrating an example of the configuration of a 3D-structured rolling strain sensor according to the present invention and the manufacturing process thereof. FIGS. 4 and FIGS. 5 are drawings showing an example of a flexible substrate having a 2D electrode pattern formed thereon according to the present invention. FIG. 6 is a drawing showing a rolling strain sensor with a 3D structure according to an embodiment of the present invention. FIG. 7 is a diagram showing the types of strain sensors according to the thickness and shape of the elastomer sheet according to the present invention. FIG. 8 is a diagram showing the measurement principle of a rolling strain sensor according to an embodiment of the present invention. FIGS. 9 to 13 are drawings showing the results of FEA analysis of the strain stress change according to the modulus of an elastomer sheet according to the present invention. FIGS. 14 and 15 are drawings showing an example of a tensile electrode angle according to the present invention and the results of FEA analysis of the stress change according thereto. FIGS. 16 and 17 are drawings showing an example of a result of a change in capacitance according to a change in elastomer thickness caused by tension, and images of a rolling strain sensor before and after tension according to the present invention. FIG. 18 is an operation flowchart illustrating a method for manufacturing a rolling strain sensor with a 3D structure according to an embodiment of the present invention. The present invention will be described in detail below with reference to the accompanying drawings. Hereinafter, repetitive descriptions and detailed descriptions of known functions and configurations that may unnecessarily obscure the essence of the invention are omitted. Embodiments of the present invention are provided to more fully explain the invention to those with average knowledge in the art. Accordingly, the shapes and sizes of elements in the drawings may be exaggerated for clearer explanation. In this document, each of the phrases such as "A or B", "at least one of A and B", "at least one of A or B", "A, B or C", "at least one of A, B and C", and "at least one of A, B, or C" may include any one of the items listed together in the corresponding phrase, or all possible combinations thereof. Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to