A wearable human body flexible antenna device based on hierarchical thin film system

Abstract

The present invention provides a wearable human body flexible antenna device based on a hierarchical film system, which has a three-layer PDMS film structure, improves the accuracy and stability of signal measurement, and ensures comfort and lightness of wearing. The top layer of the wearable human body flexible antenna device is a stretchable PDMS film, which is equipped with a flexible antenna to achieve wireless communication. The middle layer is a stress-controlled PDMS film, which is embedded with elastic wires, and its low Young's modulus design effectively controls bending stress. The bottom layer is a sticky PDMS film, which fits the skin, arranges flexible sensing electrodes to collect electrocardiogram signals, and is connected to the antenna through elastic wires. Based on the hierarchical film system, the structure improves its stability during body movement while keeping the device light and comfortable, solves the contradiction between stability and comfort in traditional designs, and achieves high-stability signal transmission.

Description

Technical Field

[0001] The invention relates to a flexible antenna device, in particular to a wearable human body flexible antenna device based on a hierarchical film system. Background Art

[0002] Through the combination of multiple disciplines and engineering technologies such as materials science, mechanics, optoelectronic engineering, and communications engineering, a flexible wearable sensor system for collecting human health signals was born. Through the systematic thin film integration and related processes of flexible sensor devices and flexible antennas, the sensor system can work on the human body surface anytime and anywhere and collect human health-related signals, such as body temperature, skin humidity, muscle signals, nerve signals, and electrocardiogram signals and other thermal, optical, electrical, and mechanical signals, and transmit them in real time through antennas to external devices such as mobile phones for visual synchronous monitoring and analysis, thereby achieving the purpose of monitoring the real-time health status of the human body.

[0003] On the basis of the above, the flexible antenna device integration system currently has the following problems that need to be improved: the current flexible antenna devices cannot meet the requirements of lightness, comfort, reliability and accuracy of signal measurement at the same time. The main reason is that the existing flexible antenna devices cannot maintain stable performance under complex deformation environments. In order to solve this problem, the existing flexible antenna devices must reduce the ductility of the film substrate and increase the thickness, which will inevitably sacrifice the comfort and lightness of the user during wearing.

[0004] It should be noted that the information disclosed in the above background technology section is only used for understanding the background of the present application, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Summary of the invention

[0005] The main purpose of the present invention is to overcome the defects existing in the above-mentioned background technology and provide a wearable human body flexible antenna device based on a hierarchical film system.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A wearable human body flexible antenna device based on a hierarchical film system, comprising:

[0008] A stretchable PDMS film, as the top layer, is arranged with a flexible antenna for wireless communication;

[0009] A stress-controlled PDMS film, as an intermediate layer, is embedded with an elastic wire, and the Young's modulus of the stress-controlled PDMS film is smaller than that of the ductile PDMS film and the adhesive PDMS film, so as to control bending stress and protect the elastic wire arranged thereon;

[0010] The sticky PDMS film, as the bottom layer, is used to fit the human skin and is arranged with flexible sensing electrodes for collecting electrocardiographic signals. The flexible sensing electrodes are connected to the flexible antenna through the elastic wire.

[0011] Furthermore, a via is arranged in the center of the floor of the flexible antenna, and the via is filled with a conductive material. The elastic wire is guided to the surface of the film system through the conductive material in the via to be connected to the signal reading circuit.

[0012] Furthermore, the elastic wire is arranged in an S-shape on the stress-controlling PDMS film.

[0013] Furthermore, the elastic conductive wire is made of a conductive resin or conductive glue having elasticity.

[0014] Furthermore, the thickness of the stress-controlled PDMS film is 100 microns.

[0015] Furthermore, the dielectric constant of each layer of PDMS film is 2-5.

[0016] Furthermore, the flexible sensing electrode is connected to the surface of the adhesive PDMS film through metal copper.

[0017] Furthermore, the flexible sensing electrode comprises a pair of ECG electrodes with a spacing of more than 50 mm.

[0018] Further, the flexible antenna is an inverted F circular arc antenna structure, the inverted F circular arc antenna structure having an arc line edge as a radiating arm, a first line edge connected to the end of the circular arc line edge, and a second line edge connected to the middle of the circular arc line edge, the first line edge of the inverted F circular arc antenna structure is connected to the circular floor of the flexible antenna, and the second line edge of the inverted F circular arc antenna structure is connected to the feeding port, and the arc line edge of the inverted F circular arc antenna structure is arranged to extend along the extension direction of the arc periphery of the circular floor of the flexible antenna.

[0019] A method for preparing a wearable human body flexible antenna device based on a hierarchical thin film system comprises the following steps:

[0020] Prepare a stretchable PDMS film on the substrate surface;

[0021] preparing an elastic wire on the stretchable PDMS film;

[0022] preparing a stress-controlled PDMS film on the stretchable PDMS film, so that the stress-controlled PDMS film completely covers the elastic wire, and the elastic wire is embedded in the stress-controlled PDMS film;

[0023] preparing a sticky PDMS film on the stress-controlled PDMS film;

[0024] preparing a flexible sensing electrode on the sticky PDMS film;

[0025] The substrate was separated and an antenna was prepared on the stretchable PDMS film.

[0026] The present invention has the following beneficial effects:

[0027] The wearable human body flexible antenna device of the present invention realizes a light and comfortable wearing experience through an innovative three-layer PDMS film structure, while ensuring the accuracy and stability of signal measurement. The topmost ductile PDMS film is arranged with a flexible antenna for wireless communication, ensuring the communication function of the device, and the middle stress-controlled PDMS film is embedded with an elastic wire, and its lower Young's modulus effectively controls the bending stress. The middle stress-controlled PDMS film has a lower Young's modulus relative to the upper ductile PDMS film and the lower viscous PDMS film. Without sacrificing the user's wearing comfort and portability, the stress control effect it produces provides good bending performance, effectively improving the performance stability of the flexible antenna device in a complex deformation environment. Through this design, even in the shape change caused by body movement, the device can maintain reliable signal measurement accuracy and communication stability, thereby solving the contradiction in the prior art that the film thickness has to be increased and the wearing comfort has to be sacrificed in order to improve stability. It is also beneficial to protect the elastic wire from damage and enhance the durability and reliability of the device. The bottommost sticky PDMS film fits the human skin and is arranged with flexible sensing electrodes for collecting ECG signals. It is connected to the flexible antenna through elastic wires to achieve effective signal transmission. The overall design of the three-layer PDMS film structure of the present invention not only solves the problem of unstable performance of traditional flexible antenna devices in complex deformation environments, but also avoids the need to sacrifice comfort and lightness to improve stability. In general, the flexible antenna substrate of the multi-layer flexible film structure of the present invention provides good tensile and bending deformation capabilities, so that the flexible antenna device can adapt to the complex strains in various wearing environments and maintain stable performance. The entire system is compact in design, small in size, and highly integrated, and can be mass-produced through modern manufacturing technologies such as nanomaterial structures and additive manufacturing, which reduces costs and improves production efficiency. The present invention not only improves the user's wearing experience, but also ensures the real-time and accuracy of health monitoring data, providing an efficient and reliable solution for the development of wearable sensing technology.

[0028] Other beneficial effects of the embodiments of the present invention will be further described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic structural diagram of a wearable human body flexible antenna device based on a hierarchical thin film system according to an embodiment of the present invention.

[0030] Figure 2 This is an exploded diagram of the hierarchical layout of a wearable human body flexible antenna device based on a hierarchical thin film system according to an embodiment of the present invention.

[0031] Figure 3 Schematic diagram of the antenna structure of a wearable human body flexible antenna device based on a hierarchical thin film system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0032] The following is a detailed description of the embodiments of the present invention. It should be emphasized that the following description is only exemplary and is not intended to limit the scope and application of the present invention.

[0033] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element. In addition, connection can be used for fixing as well as for coupling or communication.

[0034] It should be understood that the orientation or position relationship indicated by terms such as "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0035] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0036] See also Figure 1 to Figure 2, an embodiment of the present invention provides a wearable human body flexible antenna device based on a hierarchical film system, comprising: a stretchable PDMS film 1, as the top layer, arranged with a flexible antenna 5 for wireless communication; a stress-controlled PDMS film 2, as the middle layer, embedded with an elastic wire 6, the Young's modulus of the stress-controlled PDMS film 2 is smaller than that of the stretchable PDMS film 1 and the adhesive PDMS film 3, so as to control the bending stress and protect the elastic wire 6 arranged thereon; the adhesive PDMS film 3, as the bottom layer, is used to fit the human skin, and is arranged with a flexible sensing electrode 7 for collecting electrocardiogram signals, and the flexible sensing electrode 7 is connected to the flexible antenna 5 through the elastic wire 6 through the hole 4 on the stretchable PDMS film 1. In a preferred embodiment, the elastic wire 6 is arranged in an S-shaped direction on the stress-controlled PDMS film 2. Preferably, the thickness of the stress-controlled PDMS film 2 is 100 microns.

[0037] The wearable human flexible antenna device of the embodiment of the present invention designs a three-layer PDMS film structure to achieve the wearable human flexible antenna device while maintaining a light and comfortable wearing experience, while ensuring the accuracy and stability of signal measurement. The topmost ductile PDMS film 1 integrates a flexible antenna 5, which is responsible for the wireless communication function, while the middle stress-controlled PDMS film 2, due to its low Young's modulus, effectively controls the bending stress of the device in a complex deformation environment, provides good bending performance, improves performance stability, and protects the elastic wire 6 embedded therein, enhancing the durability and reliability of the device. The bottommost viscous PDMS film 3 ensures a close fit with human skin, and is arranged with a flexible sensing electrode 7 for collecting ECG signals, which is connected to the flexible antenna 5 through the elastic wire 6 to achieve effective signal transmission. This structural design cleverly solves the problem of unstable performance of traditional flexible antenna devices in deformation environments, avoids the need to sacrifice comfort and lightness to improve stability, and enables the device to adapt to complex strains in various wearing environments and maintain stable performance. In addition, the entire system is compact in design, small in size, and highly integrated, and can be mass-produced through modern manufacturing technologies such as nanomaterial structures and additive manufacturing, which reduces costs and improves production efficiency, thus providing an efficient and reliable solution for the development of wearable sensing technology.

[0038] The specific embodiments of the present invention are further described below.

[0039] See also Figures 1 to 3A wearable human body flexible sensor device includes a multi-layer flexible dielectric film, a flexible antenna 5 and a flexible sensing electrode 7. The multi-layer flexible dielectric film is used as the main body, and the flexible sensing electrode 7 and the flexible antenna 5 are respectively integrated into the upper and lower layers of the film, and an elastic wire 6 is embedded in the middle layer to introduce the electrocardiogram signal into the data reading area in the center of the film. The multi-layer flexible dielectric film has a three-layer structure, the top layer is a stretchable PDMS film 1, the middle layer is a stress-controlled PDMS film 2, and the bottom layer is a sticky PDMS film 3. The hierarchical distribution of the integrated film system is as follows: Figure 2 As shown. Among them, the Young's modulus of the stress-controllable PDMS film 2 is lower than that of the ductile PDMS film 1 and the adhesive PDMS film 3. Preferably, the dielectric constant of the PDMS film is 2-5.

[0040] like Figure 3 As shown, in one embodiment, the flexible antenna 5 adopts an inverted F arc antenna structure, which has an arc line edge 8 as a main radiation unit, a first line edge 9 connected to the end of the arc line edge, and a second line edge 10 connected to the middle of the arc line edge. The first line edge 9 of the inverted F arc antenna structure is connected to the first upper surface floor, and the second line edge 10 of the inverted F arc antenna structure is connected to the feeding port 11. The arc line edge 8 of the inverted F arc antenna structure is arranged to extend along the extension direction of the arc periphery of the first upper surface floor. The inverted F arc antenna and the flexible sensing electrode 7 transmit signals through the via 12 and the elastic wire 6 made of conductive flexible material. All elastic wires 6 start from the flexible sensing electrode 7 and concentrate to the reading circuit area in the center of the film.

[0041] The embodiment of the present invention provides a device solution for integrating a flexible wearable sensor-communication system. A flexible antenna 5, an elastic wire 6, a flexible sensor electrode 7 and an external device interface are integrated into a multilayer film structure with three layers of PDMS stretchable film as the main body, so as to realize an ultra-thin, stretchable and stable wearable health monitoring system. Among them, the three-layer PDMS stretchable film structure is the main body, a layer of sticky PDMS glue is used to fit the human skin, a layer of stretchable PDMS film is used to provide good stretching performance, and a layer of stress-controlled PDMS film 2 in the middle can provide good bending performance, control bending stress and protect the elastic wire 6 arranged thereon, so that the integrated device can take into account the stretchability, bendability and skin fit of the wearable flexible system.

[0042] The flexible sensing electrode 7 integrated on the surface of the adhesive PDMS film 3 is used to contact the surface of human skin, and the flexible sensing electrode 7 can be connected to the surface of the adhesive PDMS film 3 through metal copper. When in use, the flexible sensing electrode 7, the adhesive PDMS film 3 as a flexible film substrate, and the human skin can fit tightly together.

[0043] An inverted F arc-shaped antenna structure is arranged on the surface of the stretchable PDMS film 1, and a common deformation structure is formed by cooperating with the circular floor. In particular, the arc side strips serving as the main radiation unit of the antenna structure are parallel to the circumference of the circular floor or the ellipse, thereby improving the stretchability and bending deformation performance of the flexible antenna 5. Even if stretching and bending deformation occur, it can still work normally within the communication bandwidth without affecting the antenna RF performance.

[0044] Method for preparing flexible sensor device

[0045] A layer of ductile PDMS film 1 is prepared on the surface of the glass substrate, preferably with a thickness of 100 microns, to ensure the subsequent integration of the hierarchical structure and the overall stretchability of the film system. The mixed film can be scraped onto a mold for one-step molding, or a circular film can be prepared by spin coating and then cut.

[0046] An elastic wire 6 is prepared on the stretchable PDMS film 1. Preferably, the elastic wire 6 is made of an elastic material with excellent conductive properties such as conductive resin or conductive glue. The elastic wire 6 has an S-shaped orientation to effectively improve the tensile resistance. The elastic wire 6 is used to transmit the ECG signals collected by the ECG electrodes at both ends of the film to the central area, so as to facilitate connection with the signal reading circuit (not shown in the figure).

[0047] A stress-controlling PDMS film 2 is prepared on the stretchable PDMS film 1. At the same time, the stress-controlling PDMS film 2 should completely cover the elastic wire 6 so that it is embedded in the stress-controlling PDMS film 2. Preferably, the Young's modulus of the stress-controlling PDMS film 2 should be lower than that of the stretchable PDMS film 1. At the same time, the thickness is preferably 100 microns so that it can fully play the role of bending stress control.

[0048] The adhesive PDMS film 3 is prepared on the stress-controlled PDMS film 2. Preferably, the thickness of the adhesive PDMS film 3 is 100 micrometers to ensure the human body adhesion strength and the overall thickness of the film.

[0049] The flexible sensing electrodes 7 serving as ECG electrodes are prepared on the sticky PDMS film 3. Preferably, the distance between the ECG electrodes is greater than 50 mm to ensure the potential difference of the ECG signal.

[0050] The flexible antenna 5 is prepared on the stretchable PDMS film 1. In this embodiment, the conductive material can be processed on the stress control area by using a screen printing method, an inkjet printing method or a thin film deposition method. The conductive material can be silver or copper.

[0051] An antenna structure prepared as Figure 3As shown, it has an arc-shaped radiation arm (arc line edge 8) as a main radiation unit, a first line edge 9 connected to the end of the radiation arm, and a second line edge 10 connected to the middle of the radiation arm. The first line edge of the inverted F arc-shaped antenna structure is connected to the first upper surface floor, and the second line edge of the inverted F arc-shaped antenna structure is connected to the feeding port 11. The arc line edge of the inverted F arc-shaped antenna structure is arranged to extend along the extension direction of the arc periphery of the first upper surface floor. A via 12 is arranged on the left and right sides of the antenna floor in the center for guiding the elastic wire 6 of the middle layer to the surface of the thin film system through the conductive material filling, so as to facilitate the connection with the signal reading circuit (not shown).

[0052] In summary, compared with traditional flexible antenna technology, the present invention provides a wearable human flexible antenna device based on a hierarchical film system, and designs a three-layer PDMS film structure to improve the accuracy and stability of signal measurement, while ensuring the comfort and lightness of wearing. The top layer of the wearable human flexible antenna device is a stretchable PDMS film, which is equipped with a flexible antenna to achieve wireless communication. The middle layer is a stress-controlled PDMS film, which is embedded with elastic wires. Its low Young's modulus design effectively controls bending stress and provides good bending performance. The bottom layer is a sticky PDMS film that fits the skin, and flexible sensing electrodes are arranged to collect ECG signals, and are connected to the antenna through elastic wires. Based on the hierarchical film system, the structure improves its stability during body movement while keeping the device light and comfortable, solving the contradiction between stability and comfort in traditional designs, and achieving high-stability signal transmission.

[0053] The above content is a further detailed description of the present invention in combination with specific / preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, without departing from the concept of the present invention, it can also make several substitutions or modifications to these described embodiments, and these substitutions or modifications should be regarded as belonging to the protection scope of the present invention. In the description of this specification, the description of the reference terms "an embodiment", "some embodiments", "preferred embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily target the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In the absence of mutual contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions and modifications can be made herein without departing from the scope of protection of the patent application.

Claims

1. A wearable human body flexible antenna device based on a hierarchical thin film system, characterized in that: include: A stretchable PDMS film, as the top layer, is arranged with a flexible antenna for wireless communication; A stress-controlled PDMS film, as an intermediate layer, is embedded with an elastic wire, and the Young's modulus of the stress-controlled PDMS film is smaller than that of the ductile PDMS film and the adhesive PDMS film, so as to control the bending stress and protect the elastic wire arranged thereon; the bending performance provided by the generated stress control effect improves the performance stability and comfort of the flexible antenna device in a complex deformation environment; The sticky PDMS film, as the bottom layer, is used to fit the human skin and is arranged with flexible sensing electrodes for collecting electrocardiographic signals. The flexible sensing electrodes are connected to the flexible antenna through the elastic wire.

2. The wearable human body flexible antenna device based on a hierarchical thin film system as claimed in claim 1, characterized in that: A via is arranged in the center of the floor of the flexible antenna, and the via is filled with a conductive material. The elastic wire is guided to the surface of the thin film system through the conductive material in the via to be connected to the signal reading circuit.

3. The wearable human body flexible antenna device based on a hierarchical thin film system according to claim 1 or 2, characterized in that: The elastic wire is arranged in an S-shape on the stress-controlling PDMS film.

4. The wearable human body flexible antenna device based on a hierarchical thin film system according to claim 1 or 2, characterized in that: The elastic wire is made of conductive resin or conductive glue having elasticity.

5. The wearable human body flexible antenna device based on a hierarchical thin film system according to claim 1 or 2, characterized in that: The thickness of the stress-controlling PDMS film is 100 microns.

6. The wearable human body flexible antenna device based on a hierarchical thin film system according to claim 1 or 2, characterized in that: The dielectric constant of each layer of PDMS film is 2-5.

7. The wearable human body flexible antenna device based on a hierarchical thin film system according to claim 1 or 2, characterized in that: The flexible sensing electrode is connected to the surface of the adhesive PDMS film through metal copper.

8. The wearable human body flexible antenna device based on a hierarchical thin film system according to claim 1 or 2, characterized in that: The flexible sensing electrodes include a pair of ECG electrodes with a spacing of more than 50 mm.

9. The wearable human body flexible antenna device based on a hierarchical thin film system according to claim 1 or 2, characterized in that: The flexible antenna is an inverted F circular arc antenna structure, which has an arc line side as a radiation arm, a first line side connected to the end of the arc line side, and a second line side connected to the middle of the arc line side. The first line side of the inverted F circular arc antenna structure is connected to the circular floor of the flexible antenna, and the second line side of the inverted F circular arc antenna structure is connected to the feeding port. The arc line side of the inverted F circular arc antenna structure is arranged to extend along the extension direction of the arc periphery of the circular floor of the flexible antenna.

10. A method for preparing a wearable human body flexible antenna device based on a hierarchical thin film system according to any one of claims 1 to 9, characterized in that: The steps include: Prepare a stretchable PDMS film on the substrate surface; preparing an elastic wire on the stretchable PDMS film; preparing a stress-controlled PDMS film on the stretchable PDMS film, so that the stress-controlled PDMS film completely covers the elastic wire, and the elastic wire is embedded in the stress-controlled PDMS film; preparing a sticky PDMS film on the stress-controlled PDMS film; preparing a flexible sensing electrode on the sticky PDMS film; The substrate was separated and an antenna was prepared on the stretchable PDMS film.

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