Silver crack flexible strain sensor and manufacturing method thereof

Abstract

The application discloses a silver crack flexible strain sensor and a manufacturing method thereof, relates to a flexible sensor, and particularly relates to a plant monitoring flexible strain sensor. The application solves the technical problems of unstable adhesion of the flexible sensor and damage to the plant surface in the prior art. The silver crack flexible strain sensor comprises a substrate, a stretching layer, a conductive layer and a packaging layer. The substrate is a petal-shaped multi-arc sheet structure composed of a mixed material of PDMS and Ecoflex. The stretching layer is used for transmitting a mechanical gradient and bearing the conductive layer. The conductive layer is used for generating and transmitting sensing data. The packaging layer is used for packaging the conductive layer on the substrate. The stretching layer, the conductive layer and the packaging layer form a composite layer structure. The cross section of the composite layer structure is in an arc shape, and the concave surface of the arc shape faces the substrate. The substrate is prepared by using the mixed material of PDMS and Ecoflex, so that the tensile property and the strength of the substrate are strengthened, and the substrate is suitable for plant detection in more environments.

Description

Technical Field

[0001] This invention relates to flexible sensors, specifically to a flexible strain sensor for plant monitoring. Background Technology

[0002] Plant monitoring is generally used in agriculture, forestry, and scientific research. It is often used to quantify the growth status of plants into data, which plays an important role in plant research and cultivation.

[0003] Traditional plant detection methods typically rely on visual, optical, or rigid sensors, which cannot provide real-time, sensitive monitoring of minute leaf deformations.

[0004] Most existing flexible sensors suffer from problems such as unstable adhesion, damage to plant surfaces, or poor performance. These issues can lead to relative slippage or detachment of the sensor when leaves deform, making it difficult to accurately reflect the true deformation process. Stimulation from materials or adhesives on the plant surface can cause epidermal damage, localized water loss, yellowing, or necrosis, creating additional physiological stress on the plant surface. Furthermore, sensor coverage on the leaf surface may affect light absorption, gas exchange, and transpiration. Overly rigid or tightly fixed structures may restrict natural plant growth, causing monitoring results to deviate from the plant's true natural growth state and reducing the reliability and accuracy of the monitoring data. Additionally, it can negatively impact the plant's own growth.

[0005] Some existing flexible sensors used for plant monitoring can only monitor a single signal and cannot perform real-time acquisition and transmission of multiple signals. During the detection process, leaf deformation may be caused by a variety of factors such as normal growth, water shortage, temperature, light, or external factors. If the sensor can only monitor a single signal and cannot simultaneously collect information from the air, soil, etc., it will be difficult to distinguish whether the abnormal fluctuation of the signal is caused by normal plant growth, environmental stress, or accidental factors, thus easily leading to misjudgment. Summary of the Invention

[0006] This invention solves the technical problems of unstable bonding of flexible sensors and damage to plant surfaces in the prior art.

[0007] Option 1: The silver crack flexible strain sensor of the present invention includes: The substrate is a petal-shaped, multi-arc sheet structure made of a hybrid material of PDMS and Ecoflex. The stretch layer is used to transfer mechanical gradients and support the conductive layer; A conductive layer is used to generate and transmit sensed data. Encapsulation layer, used to encapsulate the conductive layer on the substrate; The stretching layer, the conductive layer, and the encapsulation layer form a composite layer structure with an arc-shaped cross-section, the concave surface of which faces the substrate.

[0008] In a further optimized design, the conductive layer has several cracks on its surface to transmit inductive data.

[0009] In a further optimized design, the conductive layer is made of silver.

[0010] In a further optimized design, the hardness of the encapsulation layer is higher than that of the stretching layer.

[0011] In a further optimized design, the sensor also includes a temperature sensing component; The temperature sensing component includes: a temperature sensor and a support plate; The support piece is located above the encapsulation layer, and its two ends are fixedly connected to the substrate, with a gap between the support piece and the encapsulation layer; The temperature sensor is used to collect the surface temperature of the support plate.

[0012] In a further optimized design, the support piece is configured as a trapezoidal bridge shape.

[0013] In a further optimized design, the support sheet is made of PET film.

[0014] Option 2: A method for manufacturing a flexible sensor according to the present invention, the method comprising: Substrate preparation: The base template is created using a PVA 3D printer; Pour the mixed solution of PDMS and Ecoflex into the template and cure it; After curing, remove it and use it as a substrate; The mass ratio of Ecoflex solution to PDMS solution in the mixed solution is greater than 1. Preparation of the stretch layer: The PLA is used to create the stretched layer template using a 3D printer; The PDMS solution is poured into the stretching layer template and cured. After curing, the material is removed, stretched, and then fixed onto the substrate to form a stretched layer. Fabrication of the conductive layer: Silver ions are sputtered onto the surface of the stretched layer to form a silver ion layer as a conductive layer. Fabrication of the encapsulation layer: The conductive layer was encapsulated using PDMS of different concentrations.

[0015] To further optimize the solution, the method also includes: The PET film is cut into long strips and then bent into trapezoidal bridge shapes to make a support sheet; Fix the temperature sensor onto the support plate; Attach both ends of the support piece to the substrate.

[0016] In a further optimized scheme, the mass ratio of PDMS to Ecoflex in the mixed solution is 2:3.

[0017] The beneficial effects of this invention compared to the prior art are as follows: The substrate of the silver crack flexible strain sensor described in this invention uses a hybrid material of PDMS and Ecoflex. Experimental measurements of the same size show that the elongation at break corresponding to the maximum tensile length using existing PDMS-only sensors is approximately 153%. In contrast, the hybrid material of PDMS and Ecoflex used in this application achieves an elongation at break of approximately 220% at the maximum tensile length. This means that the hybrid material used in this application possesses superior tensile strength and can adapt to leaf growth during practical use, without restricting normal leaf growth—a technical effect that existing sensors of the same type cannot achieve.

[0018] The silver crack flexible strain sensor described in this invention monitors the crack strain in the conductive layer in real time, significantly improving the sensitivity of the detection and making it suitable for more precise plant monitoring scenarios.

[0019] The silver crack flexible strain sensor of this invention integrates a temperature sensor and a flexible sensor. By using a PET film to support the temperature sensor, a bridge-shaped bending design, and a semi-cured substrate material for adhesion and fixation, it solves the technical problems of incompatibility between the two sensors, easy interference when integrating multiple signals, and unstable adhesion, thus realizing multi-signal detection. Attached Figure Description

[0020] Figure 1 This is a front view of the sensor described in Embodiment 1; Figure 2 For reduction Figure 1 Top view of the sensor shown; Figure 3 This is a schematic diagram of the signal transmission relationship of the flexible strain sensor system described in Embodiment 1; Figure 4 This is a schematic diagram of the working state of the flexible strain sensor system described in Embodiment 1; Figure 5 This is a schematic diagram of the microstructure of the conductive layer 3 of the sensor described in Embodiment 1 when the crack distance is large. Figure 6 This is a schematic diagram of the microstructure when the crack distance in the conductive layer 3 of the sensor is small, as described in Embodiment 1.

[0021] Figure description: 1. Substrate; 2. Stretching layer; 3. Conductive layer; 4. Encapsulation layer; 5. Support sheet; 6. Temperature sensor; 9. Data acquisition terminal; 10. Connecting line; 11. Data transmission system; 12. Data display system; 13. Conductive particles. Detailed Implementation

[0022] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0026] It should be noted that some of the accompanying drawings are in a very simplified form and are not to scale, and are only used to facilitate and clearly illustrate the purpose of the embodiments of the present invention.

[0027] Implementation Method 1: Refer to Figures 1-6 This embodiment describes a flexible strain sensor for silver cracks, comprising: Substrate 1 is a petal-shaped, multi-arc sheet structure made of a hybrid material of PDMS and Ecoflex. Stretching layer 2 is used to transfer mechanical gradients and support conductive layer 3; Conductive layer 3 is used to generate and transmit sensed data; Encapsulation layer 4 is used to encapsulate conductive layer 3 on substrate 1; The stretching layer 2, the conductive layer 3, and the encapsulation layer 4 form a composite layer structure. The cross-section of the composite layer structure is arc-shaped, and the concave surface of the arc-shaped structure faces the substrate 1.

[0028] In this embodiment, the stretching layer 2 is a semi-cylindrical shape with a radius of 1 mm, and its length is adjusted according to the monitored plants.

[0029] The conductive layer 3 has a thickness of 150 nanometers.

[0030] The substrate 1 material used in the sensor described in this embodiment, after curing, exhibits characteristics of being soft, stretchable, adaptable to curved surfaces, and relatively chemically stable. Both PDMS and Ecoflex are curable silicone rubber materials; after preparation and full curing, substrate 1 remains stable and is unlikely to release other components onto the blade surface. Compared to hydrogel-based sensors and those containing organic solvent-based adhesive layers, this hybrid substrate is less prone to adhesive residue, epidermal peeling, or localized chemical burns when attached to the leaf surface.

[0031] Meanwhile, PDMS materials typically have good transparency, and combined with a thin substrate structure, they can reduce shading of the light-receiving area of ​​the leaf, thus minimizing the impact on photosynthesis and normal growth. Therefore, they are less likely to cause significant damage to the leaf surface during long-term monitoring of plant leaves.

[0032] Furthermore, the PDMS and Ecoflex blend has better tensile properties and adhesion than pure PDMS, and better light and air permeability than pure Ecoflex. Therefore, it is more suitable as a base layer for adhesion to plant leaves. Combined with the stretchable petal-shaped multi-arc structure of base 1, it can change accordingly with the growth of the leaves and will not fall off due to the growth of the leaves.

[0033] Based on the above principle, the base layer 1 of the sensor described in this embodiment has good tensile strength, which allows it to adhere to the leaf surface during the monitoring process and change accordingly with the growth of the leaf surface, without restricting the normal growth of the leaf surface or affecting the normal light and respiration of the plant.

[0034] The sensor described in this embodiment can also be paired with a connecting cable 10 to facilitate the output of electrical signals and signal transmission with data acquisition equipment.

[0035] In practical applications, the sensor described in this embodiment can be used in conjunction with the data transmission system 11 and the data display system 12 to form a flexible strain sensor system, such as... Figure 3 and 4The silver crack flexible strain sensor serves as the data acquisition terminal 9, used to collect plant deformation parameters. This collected data is transmitted in real time to the data display system 12 via the data transmission system 11. Finally, the data display system 12 can clearly grasp the relevant data and information of the plant, thereby providing reliable data support for plant research and the formulation of cultivation plans.

[0036] Implementation Method Two: Refer to Figure 5 and Figure 6 This embodiment is an optimized design of the silver crack flexible strain sensor described in Embodiment 1. In this embodiment, the conductive layer 3 has several cracks on its surface for transmitting sensing data.

[0037] The conductive layer 3 of the sensor described in this embodiment has several cracks, which are conductive pathways between conductive particles 13 to achieve high-precision sensing.

[0038] Due to the tunneling effect, even a small amount of stretching, bending, or compression from the outside can cause a significant change in the distance between surface microstructures, thereby causing the conductive particles 13 to connect or break, which in turn causes a sensitive change in the resistance of the flexible sensor.

[0039] like Figure 5 When the relative distance between the two sides is large, there are fewer conductive paths.

[0040] like Figure 6 When the relative distance between the two sides is small, the number of conductive paths increases.

[0041] The cracks can be regular-shaped cracks or irregular cracks.

[0042] To improve the sensitivity of the sensor, the stretching layer 2 in this embodiment can be fabricated using 3D printing. Therefore, the surface of the stretching layer 2 will have a micron-level uneven structure resulting from printing textures, material curing shrinkage, or limitations in printing precision. These microstructures can manifest as fine stripes, layered steps, micro-protrusions, or irregular rough structures distributed along the printing path, thereby further optimizing the sensor's fundamental performance.

[0043] Implementation Method 3: This implementation method is an optimized design of the silver crack flexible strain sensor described in Implementation Method 1. In this implementation method, the material of the conductive layer 3 is a silver layer.

[0044] In this embodiment, the conductive layer 3 is made of silver. The choice of silver as the conductive layer 3 takes advantage of the high conductivity and easy film formation properties of silver material itself, as well as the characteristic that it can form a crack structure on the surface of the pre-stretched flexible substrate 1, thereby improving the detection accuracy and practicality of the flexible strain sensor in monitoring plant leaf growth.

[0045] Furthermore, the silver layer possesses high electrical conductivity and excellent film-forming properties, enabling the formation of low-resistance conductive pathways even at relatively thin thicknesses. In practical applications, the stretching layer 2 is made of a material that differs from the silver layer in terms of elastic modulus, ductility, and recovery capability. This causes localized stress concentration in the silver layer during the recovery process of the substrate 1, resulting in the formation of microcracks on the surface and further enhancing the sensor's sensitivity.

[0046] Implementation Method 4: This implementation method is an optimized design of the silver crack flexible strain sensor described in Implementation Method 1. In this implementation method, the hardness of the encapsulation layer 4 is higher than that of the stretching layer 2.

[0047] In practical use, the stretching layer 2 effectively transfers macroscopic deformation to the silver conductive layer 3, causing the cracks in the conductive layer 3 to open and close, resulting in changes in the contact area and reconstruction of the conductive path. In this embodiment, the stretching layer 2 should not be too soft. If the stretching layer 2 is too soft, the deformation is easily absorbed by the substrate 1, leading to a decrease in sensor response and an increase in hysteresis.

[0048] The PDMS of the encapsulation layer 4 is used to achieve encapsulation protection of the silver layer and interface buffering without significantly restricting the opening and closing of silver cracks.

[0049] In this embodiment, setting the hardness of the encapsulation layer 4 to be higher than that of the stretching layer 2 can achieve different strain gradients between the stretching layer 2 and the encapsulation layer 4, thereby protecting the sensor surface from damage.

[0050] In this embodiment, the difference in hardness between the encapsulation layer 4 and the stretching layer 2 is preferably achieved by using different concentrations of PDMS. Furthermore, materials formed by different concentrations of PDMS have different elastic moduli and can also achieve different degrees of stretching, so as to protect the surface silver cracks from being overstretched or damaged by external influences.

[0051] The two different PDMS layers form different mechanical gradients, which helps to improve the stability of the conductive layer 3 during deformation, the controllability of cracks, and the reliability under long-term use. Furthermore, it can solve the problems of easy detachment of the conductive layer in silver cracks, uncontrollable cracks, poor cycle stability, and insufficient reliability in long-term use.

[0052] In this embodiment, the ratio of PDMS main agent to curing agent used in the stretching layer 2 is preferably 10:1, and the ratio of PDMS main agent to curing agent used in the encapsulation layer 4 is preferably 20:1.

[0053] Implementation Method 5: Refer to Figure 1 , Figure 2 This embodiment describes an optimized design of the silver crack flexible strain sensor described in Embodiment 1. In this embodiment, the sensor further includes a temperature sensing component. The temperature sensing component includes: a temperature sensor 6 and a support plate 5; The support piece 5 is located above the encapsulation layer 4, and its two ends are fixedly connected to the substrate 1, with a gap between the support piece 5 and the encapsulation layer 4.

[0054] The silver crack flexible strain sensor described in this embodiment integrates a temperature sensor 6 and a flexible sensor, enabling multi-signal acquisition. By obtaining the acquired data, relevant data and information about the plant can be clearly understood, thereby allowing for timely regulation.

[0055] In this embodiment, the temperature sensor 6 uses infrared thermometry to measure the temperature of plant leaves. The gap between the support plate 5 and the encapsulation layer 4 is determined based on the ability of the temperature sensor 6 on the support plate 5 to stably measure the temperature of the leaf surface. That is, the distance between the temperature sensor 6 and the leaf surface is adjusted according to the actual temperature measurement.

[0056] The sensor described in this embodiment integrates a flexible sensor with a temperature sensor 6. This approach solves the practical application problems of long development cycles and high development difficulty when using flexible sensors for plant data monitoring. Using this method, the development cycle can be significantly reduced, achieving more accurate, stable, and faster data measurement. Simultaneous acquisition of multiple signals is also possible. In practical use, a complete system can be configured to further achieve comprehensive monitoring and control. It also offers greater scalability. In practical applications, other functional sensors can be superimposed to achieve different functions for plant monitoring, smart agriculture, greenhouses, and other scenarios.

[0057] Implementation Method Six: Refer to Figure 1 This embodiment describes an optimized design of a silver crack flexible strain sensor as described in Embodiment 5. In this embodiment, the support piece 5 is configured as a trapezoidal bridge shape.

[0058] In this embodiment, the support plate 5 is configured as a bridge to enhance its supporting force, thereby achieving a stable connection between the temperature sensor 6 and the flexible sensor.

[0059] In this embodiment, when the support piece 5 is a rigid support and is connected to the base 1, the material of the semi-cured flexible base 1 can be used for bonding at the connection point. This ensures the stable fit between the temperature sensor 6 and the flexible sensor, and also avoids the rigid component pressing directly on the blade, thus ensuring the overall flexibility and adhesion.

[0060] Implementation Method Seven: This implementation method is an optimized design of the silver crack flexible strain sensor described in Implementation Method Five. In this implementation method, the support sheet 5 is made of PET film.

[0061] To support the distance between the infrared temperature sensor 6 and the blade, the support sheet 5 in this embodiment is made of PET film.

[0062] The temperature sensor 6 described in this embodiment is rigid, while a flexible sensor requires high flexibility to attach to the blade. Direct bonding of the two would affect the overall flexibility, attachment stability, and signal transmission stability. Therefore, a PET film with a certain supporting strength is selected to support the temperature sensor 6, providing a certain degree of flexible support and enabling compatibility between the rigid sensor and the flexible layer.

[0063] In existing technologies, it is difficult to achieve multi-signal acquisition. The main technical problem is that temperature sensors are rigid, while flexible sensors require high flexibility to adhere to the leaves. Direct bonding of the two would affect the overall flexibility, adhesion stability, and signal transmission stability. In this embodiment, the temperature sensor 6 uses infrared thermometry, which requires maintaining a certain relative distance from the plant leaf surface. Therefore, a PET film with a certain supporting strength is selected to support the temperature sensor, providing a certain degree of flexible support and enabling compatibility between the rigid sensor and the flexible layer.

[0064] Implementation Method Eight: This implementation method describes a method for manufacturing a flexible sensor, wherein the flexible sensor is any one of the flexible sensors described in Implementation Methods One to Seven, and the method includes: Preparation of substrate 1: The base template is created using a PVA 3D printer; Pour the mixed solution of PDMS and Ecoflex into the template and cure it; After curing, remove it and use it as substrate 1; The mass ratio of Ecoflex solution to PDMS solution in the mixed solution is greater than 1. Preparation of stretch layer 2: The PLA is used to create the stretched layer template using a 3D printer; The PDMS solution is poured into the stretching layer template and cured. After curing, the material is removed, stretched, and then fixed onto the substrate 1 to form a stretch layer 2. Fabrication of conductive layer 3: Silver ions are sputtered onto the surface of the stretching layer 2 to form a silver ion layer as a conductive layer 3; Fabrication of encapsulation layer 4: The conductive layer 3 was encapsulated using PDMS of different concentrations.

[0065] In this embodiment, the preferred mass ratio of the PDMS and Ecoflex mixture is 2:3.

[0066] The concentration of the PDMS solution used in the stretching layer 2 can be such that the ratio of the main agent to the curing agent is 10:1.

[0067] The concentration of the PDMS solution used in the encapsulation layer 4 can be 20:1, where the ratio of the main agent to the curing agent is 20:1.

[0068] The silver ion sputtering can be achieved using an ion sputtering instrument.

[0069] In this embodiment, the stretching layer 2 is stretched axially. When the sensor is actually attached to the plant surface, the axial stretching direction is preferably consistent with the main growth elongation direction of the plant leaves. This ensures that the curved surface can generate significant surface strain when stretched or bent.

[0070] In practical applications, by limiting the pre-stretching direction to the axial direction of the semi-cylinder, the silver conductive layer 3 is more likely to form a crack structure corresponding to the axial stretching during subsequent release and deformation, thereby improving the performance of the sensor.

[0071] The flexible sensor described in this embodiment can generate microcracks through pre-stretching after fabrication to achieve preliminary detection of plants. Furthermore, changes in the sample length during monitoring will also generate microcracks of varying degrees to improve sensor sensitivity and further enhance detection accuracy.

[0072] In this embodiment, the stretched layer 2 in the sensor is fabricated using 3D printing. Therefore, the surface of the stretched layer 2 acquires a micron-level uneven structure resulting from printing textures, material curing shrinkage, or limitations in printing precision. These microstructures can manifest as fine stripes, layered steps, micro-protrusions, or irregular rough structures distributed along the printing path, thereby further optimizing the sensor's fundamental performance.

[0073] Implementation Method Nine: This implementation method is an optimized design of the flexible sensor fabrication method described in Implementation Method Eight. In this implementation method, the method further includes: The PET film is cut into long strips and then bent into trapezoidal bridge shapes to make a support sheet 5; The temperature sensor 6 is fixed on the support plate 5; The two ends of the support piece 5 are attached to the substrate 1.

[0074] Implementation Method 10: This implementation method is an optimized design of the flexible sensor manufacturing method described in Implementation Method 9. In this implementation method, the PET film is adhered to the substrate 1 by the material of the semi-cured substrate 1.

[0075] In the prior art, adhesives are used for adhesion on substrate 1. However, due to different media, adhesives may cause unstable adhesion and further affect the test results. In order to avoid the above situation, this embodiment uses a semi-cured substrate 1 material that is the same as the substrate 1 material for bonding.

Claims

1. A flexible strain sensor for silver cracks: characterized in that, The silver crack flexible strain sensor includes: The substrate (1) is a petal-shaped multi-arc sheet structure made of a mixture of PDMS and Ecoflex. The stretching layer (2) is used to transfer the mechanical gradient and carry the conductive layer (3); The conductive layer (3) is used to generate and transmit sensing data; Encapsulation layer (4) is used to encapsulate the conductive layer (3) on the substrate (1); The stretching layer (2), the conductive layer (3), and the encapsulation layer (4) form a composite layer structure with a circular arc-shaped cross section, the concave surface of which faces the substrate (1).

2. The silver crack flexible strain sensor according to claim 1, characterized in that, The conductive layer (3) has several cracks on its surface, which are used to transmit inductive data.

3. The silver crack flexible strain sensor according to claim 1, characterized in that, The conductive layer (3) is made of silver.

4. The silver crack flexible strain sensor according to claim 1, characterized in that, The hardness of the encapsulation layer (4) is higher than that of the stretching layer (2).

5. The silver crack flexible strain sensor according to claim 1, characterized in that, The sensor also includes a temperature sensing component; The temperature sensing component includes: a temperature sensor (6) and a support plate (5). The support piece (5) is located above the encapsulation layer (4), and its two ends are fixedly connected to the substrate (1). A gap is left between the support piece (5) and the encapsulation layer (4). The temperature sensor is used to collect the surface temperature of the support plate (5).

6. A flexible strain sensor for silver cracks according to claim 5, characterized in that, The supporting piece (5) is configured as a trapezoidal bridge shape.

7. A flexible strain sensor for silver cracks according to claim 5, characterized in that, The support sheet (5) is made of PET film.

8. A method for manufacturing a flexible sensor, wherein the flexible sensor is the flexible sensor according to any one of claims 1 to 7, characterized in that, The method includes: Preparation of substrate (1): The base template is created using a PVA 3D printer; Pour the mixed solution of PDMS and Ecoflex into the template and cure it; After curing, it is taken out as a substrate (1); The mass ratio of Ecoflex solution to PDMS solution in the mixed solution is greater than 1. Preparation of the stretch layer (2): The PLA is used to create the stretched layer template using a 3D printer; The PDMS solution is poured into the stretching layer template and cured. After curing, the material is removed and stretched, and then fixed onto the substrate (1) to form a stretch layer (2). Preparation of conductive layer (3): Silver ions are sputtered onto the surface of the stretching layer (2) to form a silver ion layer as a conductive layer (3). Fabrication of encapsulation layer (4): The conductive layer (3) was encapsulated using PDMS of different concentrations.

9. A method for fabricating a flexible sensor according to claim 8, characterized in that, The method further includes: The PET film is cut into long strips and then bent into trapezoidal bridge shapes to make a support sheet (5). The temperature sensor (6) is fixed on the support plate (5); The two ends of the support piece (5) are attached to the substrate (1).

10. A method for fabricating a flexible sensor according to claim 8, characterized in that, The mass ratio of PDMS to Ecoflex in the mixed solution is 2:3.

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