A flexible wearable multi-parameter sensing device based on LC resonance
Patent Information
- Application Number
- CN202610885591.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-06-18
- Publication Date
- 2026-08-21
AI Technical Summary
[0003]现有传感装置多针对单一物理量或单一生化指标进行检测，例如，关节运动监测多采用单独的弯曲传感器或应变传感器，汗液分析则多采用单独的生化传感器，上述结构虽然能够分别完成特定检测任务，但在人体运动状态和局部代谢状态需要同步监测的场景下，通常需要将多个传感器分别贴附在皮肤表面，不仅贴附位置分散、信号难以对应，而且各传感器通常需要分别引线、分别供电，导致整体结构复杂、佩戴不便，连续监测和便携使用的需求
[0018]与现有技术相比，本发明的基于LC谐振的柔性可穿戴多参数传感装置将角度检测、应变检测和乳酸检测集成于同一柔性基底上，并采用LC无线无源方式统一读取，实现了人体运动参数与生化参数的同步检测，既减少了外接线路和供电结构，提升了柔性贴附性和穿戴便利性，又提高了多参数检测的一体化程度和动态监测稳定性。
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Figure CN122604365A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of flexible sensing technology, specifically to a flexible wearable multi-parameter sensing device based on LC resonance. Background Technology
[0002] With the development of flexible electronics and wearable detection technology, sensing devices built on flexible substrates have good application prospects in fields such as human motion monitoring, health detection, and physiological information collection due to their bendability, stretchability, and ease of attachment to the human body surface. LC resonance technology is a detection technology based on the coupling of inductance and capacitance to form a resonant circuit. Its resonant frequency is related to the inductance and capacitance values in the circuit. When external forces cause changes in inductance or capacitance, the resonant frequency will change accordingly, thus enabling non-contact detection through an external reading coil. LC resonance technology is characterized by being wireless and passive, having a simple structure, being easy to miniaturize, and being easy to integrate.
[0003] Existing sensing devices are mostly designed to detect a single physical quantity or a single biochemical index. For example, joint motion monitoring often uses a single bending sensor or strain sensor, while sweat analysis often uses a single biochemical sensor. Although the above structures can perform specific detection tasks, in scenarios where the human body's motion state and local metabolic state need to be monitored simultaneously, multiple sensors usually need to be attached to the skin surface separately. This not only results in scattered attachment positions and difficulty in signal correspondence, but also requires each sensor to have its own lead wire and power supply, leading to a complex overall structure and inconvenient wearing, thus meeting the needs of continuous monitoring and portable use. Summary of the Invention
[0004] To achieve the above objectives, the present invention provides the following technical solution: a flexible wearable multi-parameter sensing device based on LC resonance, comprising: a flexible substrate; an angle sensing unit, wherein the angle sensing unit is used to generate a wirelessly readable change in resonance parameters when the flexible substrate is bent; a strain sensing unit, wherein the strain sensing unit is used to generate a wirelessly readable change in resonance parameters when the flexible substrate is subjected to tensile deformation; and a lactic acid sensing unit, wherein the lactic acid sensing unit is used to generate a wirelessly readable change in resonance parameters when in contact with a lactic acid-containing liquid; the angle sensing unit, strain sensing unit, and lactic acid sensing unit are respectively connected to corresponding LC resonant structures, and the sensing device is electromagnetically coupled to the LC resonant structure through an external reading coil to achieve wireless passive detection of angle, strain, and lactic acid concentration.
[0005] Preferably, the angle sensing unit is disposed in a region suitable for bending on the flexible substrate and is configured as a flexible resonant structure that causes changes in equivalent inductance and / or equivalent capacitance when the flexible substrate is bent; when the flexible substrate bends with human skin, the spacing between conductive patterns, local overlapping area, bending radius or coil spatial distribution in the angle sensing unit changes, thereby causing the resonant frequency of the corresponding LC resonant structure to shift, so as to achieve wireless characterization of angle changes.
[0006] Preferably, the strain sensing unit includes a liquid metal microchannel formed inside or on the surface of the flexible substrate. The liquid metal microchannel constitutes a planar spiral variable inductor coil. The variable inductor coil is coupled with a capacitor element to form an LC resonant structure for characterizing tensile deformation. When the flexible substrate is stretched, the change in the geometric dimensions of the variable inductor coil causes a change in the inductance value, thereby causing a change in the resonant frequency of the LC resonant structure.
[0007] Preferably, the angle sensing unit, strain sensing unit, and lactic acid sensing unit correspond to different LC resonance parameter ranges. By differentiating the inductance and / or capacitance values of each unit, the external reading coil can identify the corresponding resonance peak changes during frequency scanning, thereby achieving independent reading of angle, strain, and lactic acid concentration, and reducing crosstalk between different sensing units.
[0008] Furthermore, the conductive medium in the liquid metal microchannel is preferably a conductive material that is liquid at room temperature and has stable conductivity, so that the microchannel remains continuously conductive when the flexible substrate is repeatedly stretched, thereby improving the stability and durability of strain detection.
[0009] Preferably, the variable inductor coil is a rectangular or square planar spiral coil and is arranged along the force direction of the flexible substrate, so that the deformation signal can be wirelessly represented by the change of the outer dimensions of the variable inductor coil during the axial stretching process of the flexible substrate.
[0010] Preferably, the lactic acid sensing unit includes a flexible interdigital electrode and a lactic acid sensitive layer covering the surface of the flexible interdigital electrode. The flexible interdigital electrode is connected to an inductor coil to form an LC resonant structure for lactic acid detection. The lactic acid sensitive layer causes a change in the resonant parameters of the LC resonant structure through a change in dielectric properties after contacting a lactic acid-containing liquid.
[0011] Furthermore, after the lactic acid sensitive layer comes into contact with a lactic acid-containing liquid, its dielectric constant changes, thereby altering the equivalent capacitance value of the flexible interdigitated electrode. This, in turn, causes a shift in the resonant frequency through the LC resonant structure formed with the inductor coil, thus enabling wireless detection of lactic acid concentration.
[0012] Preferably, the lactic acid sensitive layer comprises a composite sensitive medium formed of phenol blue and polyvinyl chloride, which covers the surface of the flexible interdigitated electrode and serves as a lactic acid responsive material.
[0013] Preferably, the sensing device is attached to the joint area or other skin surface of the human body to simultaneously acquire information on angle changes, local strain, and sweat lactic acid concentration during human activities, thereby making it suitable for wearable sports monitoring, rehabilitation assessment, and continuous detection of physiological status.
[0014] Preferably, the flexible interdigitated electrode is disposed on a PET substrate, and the flexible interdigitated electrode includes a chromium layer and a gold layer disposed sequentially to form a conductive electrode structure for lactic acid detection, wherein the chromium layer has a thickness of 3 nm and the gold layer has a thickness of 70 nm.
[0015] Preferably, the lactic acid sensitive layer is formed on the surface of the flexible interdigitated electrode by spin coating. The phenol blue is dissolved in N,N-dimethylacetamide and then mixed with polyvinyl chloride to form a sensitive layer solution. The sensitive layer solution is filtered through a filter membrane and then spin-coated onto the surface of the flexible interdigitated electrode, and then dried to form the lactic acid sensitive layer.
[0016] Preferably, the angle sensing unit, strain sensing unit, and lactic acid sensing unit are integrated on the same flexible substrate in a layered manner, wherein the coil layer and the interdigitated electrode layer are disposed in different regions on the same side of the flexible substrate or on opposite sides, so as to reduce mutual interference between the sensing units.
[0017] Preferably, the flexible substrate is PDMS, medical silicone, PET, PI or a combination thereof, the sensing device is fixed to the surface of human skin by medical tape, the external reading coil is electromagnetically coupled to the LC resonant structure, and the output signal of the sensing device is read by recording parameters S11 and S21.
[0018] Compared with existing technologies, the flexible wearable multi-parameter sensing device based on LC resonance of the present invention integrates angle detection, strain detection and lactic acid detection on the same flexible substrate, and uses LC wireless passive method to read them in a unified manner, realizing the synchronous detection of human motion parameters and biochemical parameters. This not only reduces external circuits and power supply structure, improves flexible adhesion and wearing convenience, but also improves the integration of multi-parameter detection and dynamic monitoring stability. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is an exploded view of the entire invention; Figure 3 This is a schematic diagram of the strain sensing unit of the present invention; Figure 4 This is a schematic diagram of the structure of the capacitor element of the present invention; Figure 5 This is a schematic diagram of the structure of the variable inductor coil of the present invention; Figure 6 This is a schematic diagram of the angle sensing unit of the present invention; Figure 7 This is a schematic diagram of the solution microcavity structure of the present invention; Figure 8 This is a schematic diagram of the angle sensing structure of the present invention; Figure 9 This is a schematic diagram of the structure of the lactic acid sensing unit of the present invention; Figure 10 This is a schematic diagram of the structure of the lactic acid sensitive layer of the present invention; Figure 11 This is a schematic diagram of the structure of the flexible interdigitated electrode of the present invention; Figure 12 This is a schematic diagram of the solution microcavity forming of the present invention; Figure 13 This is a schematic diagram of the working state of the angle sensing unit of the present invention; Figure 14 This is a schematic diagram illustrating the preparation of the microchannel template of the present invention; Figure 15 This is a schematic diagram of the bonding of the microchannel structure of the present invention; Figure 16 This is a schematic diagram of the liquid metal filling and surface-mount capacitor coupling package of the present invention.
[0020] In the figure: 100, strain sensing unit; 200, angle sensing unit; 300, lactic acid sensing unit; 210, flexible cavity substrate; 220, solution microcavity; 230, angle sensing structure; 110, liquid metal microchannel; 120, variable inductor coil; 130, capacitor element; 310, lactic acid sensitive layer; 320, flexible interdigitated electrode.
Claims
1. A flexible wearable multi-parameter sensing device based on LC resonance, characterized in that, include: Flexible substrate; An angle sensing unit (200) is used to generate a change in resonant parameters that can be wirelessly read when the flexible substrate is bent. A strain sensing unit (100) is used to generate a change in resonant parameters that can be wirelessly read when the flexible substrate is subjected to tensile deformation. Lactic acid sensing unit (300), the lactic acid sensing unit (300) is used to generate a change in resonant parameters that can be wirelessly read when in contact with a lactic acid-containing liquid; The angle sensing unit (200), strain sensing unit (100) and lactic acid sensing unit (300) are respectively connected to the corresponding LC resonant structure, and the sensing device is electromagnetically coupled to the LC resonant structure through an external reading coil to realize wireless passive detection of angle, strain and lactic acid concentration.
2. The flexible wearable multi-parameter sensing device based on LC resonance according to claim 1, characterized in that: The strain sensing unit (100) includes a liquid metal microchannel (110) formed inside or on the surface of a flexible substrate. The liquid metal microchannel (110) constitutes a planar spiral variable inductor coil (120). The variable inductor coil (120) is coupled with a capacitor element (130) to form an LC resonant structure for characterizing tensile deformation. When the flexible substrate is stretched, the inductance value changes due to the change in the geometry of the variable inductor coil (120), thereby causing the resonant frequency of the LC resonant structure to change.
3. The flexible wearable multi-parameter sensing device based on LC resonance according to claim 2, characterized in that: The variable inductor coil (120) is a rectangular or square planar spiral coil and is arranged along the force direction of the flexible substrate so that the deformation signal can be wirelessly represented by the change in the external dimensions of the variable inductor coil (120) during the axial stretching process of the flexible substrate.
4. The flexible wearable multi-parameter sensing device based on LC resonance according to claim 1, characterized in that: The lactic acid sensing unit (300) includes a flexible interdigital electrode (320) and a lactic acid sensitive layer (310) covering the surface of the flexible interdigital electrode (320). The flexible interdigital electrode (320) is connected to an inductor coil to form an LC resonant structure for lactic acid detection. The lactic acid sensitive layer (310) causes a change in the resonant parameters of the LC resonant structure through a change in dielectric properties after contacting a lactic acid-containing liquid.
5. The flexible wearable multi-parameter sensing device based on LC resonance according to claim 4, characterized in that: The lactic acid sensitive layer (310) includes a composite sensitive medium formed of phenol blue and polyvinyl chloride, which covers the surface of the flexible interdigitated electrode (320) and serves as a lactic acid responsive material.
6. The flexible wearable multi-parameter sensing device based on LC resonance according to claim 5, characterized in that: The flexible interdigitated electrode (320) is disposed on a PET substrate, and the flexible interdigitated electrode (320) includes a chromium layer and a gold layer disposed sequentially to form a conductive electrode structure for lactic acid detection.
7. The flexible wearable multi-parameter sensing device based on LC resonance according to claim 6, characterized in that: The chromium layer has a thickness of 3 nm, and the gold layer has a thickness of 70 nm.
8. The flexible wearable multi-parameter sensing device based on LC resonance according to claim 4, characterized in that: The lactic acid sensitive layer (310) is formed on the surface of the flexible interdigitated electrode (320) by spin coating. The phenol blue is dissolved in N,N-dimethylacetamide and then mixed with polyvinyl chloride to form a sensitive layer solution. The sensitive layer solution is filtered through a filter membrane and then spin coated on the surface of the flexible interdigitated electrode (320), and then dried to form the lactic acid sensitive layer 310.
9. The flexible wearable multi-parameter sensing device based on LC resonance according to claim 1, characterized in that: The angle sensing unit (200), strain sensing unit (100) and lactic acid sensing unit (300) are integrated on the same flexible substrate in a layered manner, wherein the coil layer and the interdigitated electrode layer are disposed in different regions on the same side of the flexible substrate or on opposite sides, so as to reduce mutual interference between the sensing units.
10. The flexible wearable multi-parameter sensing device based on LC resonance according to claim 1, characterized in that: The flexible substrate is PDMS, medical silicone, PET, PI or a combination thereof. The sensing device is fixed to the surface of human skin with medical tape. An external reading coil is electromagnetically coupled to the LC resonant structure, and the output signal of the sensing device is read by recording parameters S11 and S21.