Wearable composite sensor for strain and positioning

Abstract

A wearable composite sensor for strain and positioning, comprising: a strain sensing module and a position identification module. When the position identification module does not experience any external force, a sensitive layer and a metal electrode layer are not in contact with each other, and no conductive path is generated; when the sensitive layer receives pressure from the interphalangeal joint of a finger by means of a sleeve ring (12), the pressed part of the sensitive layer passes through an inert gas spacer layer (4) and is in contact with the metal electrode layer, a first electrode (5) and an output electrode (9) form a conductive path, and a position signal is generated by means of a microstructure substrate (8); and when the finger bends, the strain sensing module transmits bending stress to the sensitive layer by means of the sleeve ring (12), and when the sensitive layer receives the bending stress, the resistance between the first electrode (5) and the second electrode (9) changes, thereby generating a strain signal. The sensor has a simple structure, involves a simple fabrication process, and has high recognition accuracy and high strain sensing sensitivity.

Description

A wearable composite sensor for strain and positioning Technical Field

[0001] This invention belongs to the field of sensors, specifically relating to a wearable composite sensor for strain and positioning. Background Technology

[0002] With the rapid development of intelligent technology, the performance of high-precision hand motion monitoring systems in complex operations and high-precision applications such as virtual reality (VR), augmented reality (AR), smart gloves, and robotics has made it impossible for them to provide comprehensive and integrated motion feedback.

[0003] The demand in this field is constantly increasing. Precise hand motion capture can not only significantly improve the user experience but also enhance operational efficiency and accuracy. However, most existing hand motion monitoring sensors can only measure a single physical quantity, such as the bending angle of a finger. This limitation restricts the sensors from utilizing the multiple sensory units contained within human skin, such as position sensors, pressure sensors, strain sensors, and temperature sensors. These sensory units work together to enable humans to respond accurately to external stimuli. Position sensors are responsible for sensing vibrations and displacements of the skin, pressure sensors detect changes in pressure on the skin, strain sensors monitor the stretching of the skin and tissues, and temperature sensors sense changes in temperature. The design goal of biomimetic sensors is to mimic these sensory units to achieve comprehensive monitoring of hand movements, thereby enhancing the sensor's overall functionality and responsiveness.

[0004] However, existing biomimetic strain measurement techniques typically rely on finger flexion signals to infer the overall flexion angle, a method prone to analytical errors. Since inverse kinematics calculations may fail to accurately reflect the angle of each joint, this error can lead to insufficient operational precision in practical applications. Although composite sensors attempt to integrate multiple functions to simultaneously acquire flexion angle and position information, they still face numerous challenges, including complex circuit layouts, cumbersome sensor structures, high fabrication difficulty, low accuracy, and signal interference. These issues make it difficult for existing composite sensors to meet the demands of high-precision monitoring in practical applications. Summary of the Invention

[0005] To solve the above technical problems, the present invention proposes a wearable composite sensor for strain and positioning, comprising: a metal electrode layer, a sensitive layer, a non-conductive pad (3), an inert gas spacer layer (4), a first electrode (5), a non-conductive pad (6), a second electrode (9), a lead wire (10), an insulating encapsulation (11), and a collar (12).

[0006] The metal electrode layer, sensitive layer, non-conductive pad (3), inert gas spacer layer (4), first electrode (5), non-conductive pad (6), and second electrode (9) together constitute the position recognition module;

[0007] The metal electrode layer is composed of a metal coating (1) and a coating substrate (2), wherein the metal coating (1) is attached to the surface of the coating substrate (2);

[0008] The sensitive layer consists of a conductive sensitive material layer (7) and a microstructure substrate (8), wherein the conductive sensitive material layer (7) is attached to the surface of the microstructure substrate (8);

[0009] The metal film (1) is externally connected to the lead wire (10) as an output electrode;

[0010] The sensitive layer and the metal electrode layer are supported by a plurality of non-conductive pads (6), and filled with inert gas to form the inert gas spacer layer (4).

[0011] The first electrode (5) and the second electrode (9) are respectively connected to the two ends on the same side of the non-conductive pad (3);

[0012] The non-conductive pad (3) surrounds the periphery of the sensitive layer and the metal electrode layer, and one end with the first electrode (5) and the second electrode (9) is connected to the sensitive layer;

[0013] When the position recognition module is not subjected to external force, the sensitive layer and the metal electrode layer do not contact each other and do not generate a conductive path. When the sensitive layer is subjected to pressure from the interphalangeal joint of a finger through the collar (13), the sensitive layer at the pressure point passes through the inert gas spacer layer (4) and comes into contact with the metal electrode layer. The low resistance of the metal film plated (1) on the metal electrode layer comes into contact with the high resistance of the conductive sensitive material layer (7) on the sensitive layer. The first electrode and the output electrode form a conductive path and generate a position signal through the microstructure substrate (8).

[0014] The sensitive layer, the first electrode (5), and the second electrode (9) together form a strain sensing module;

[0015] The first electrode (5) and the second electrode (9) are bonded to both sides of the sensitive layer.

[0016] The first electrode (5) and the second electrode (9) are respectively connected to the lead wire (10) and serve as the input electrode and the second electrode (9) serves as the output electrode;

[0017] When the finger is bent, the strain sensing module transmits bending stress to the sensitive layer through the collar (13). When the sensitive layer is subjected to bending stress, the resistance between the first electrode (5) and the second electrode (9) changes, generating a strain signal.

[0018] The outer side of the insulating package (11) is connected to the collar (12); the insulating package (11) encloses the position identification module and the strain sensing module inside.

[0019] The beneficial effects of this invention are:

[0020] 1) Compared with a single detection sensor, the composite sensor of the present invention uses a sensitive layer and three electrodes to simultaneously detect two signals: bending strain and position positioning. The microstructure design of the sensitive layer improves the signal resolution of the sensor, enabling more precise detection and differentiation of different signal intensities, and reducing coupling interference. The overall sensor mainly achieves sensing through the sensitive layer and metal electrode layer, and has a stable and simple structure.

[0021] 2) The sensitive layer of the composite sensor of the present invention serves as both a high-resistance layer for positioning and a sensitive layer for bending stress sensing. By integrating positioning and bending stress sensing functions into the same sensitive layer, the sensor structure is simplified, and the size and complexity of the sensor are reduced. A single sensitive layer can be used to measure bending stress or, in conjunction with a metal electrode layer, for high-precision positioning, thereby improving the overall efficiency of the sensor.

[0022] 3) The sensitive layer of the composite sensor of the present invention adopts a microstructure design to optimize stress response and acts as a high-resistance layer in the positioning function to ensure accurate positioning. The stress measurement and positioning functions are integrated into a single sensitive layer, which greatly simplifies the structural design of the sensor. This integration not only reduces the number of required components and lowers production costs, but also simplifies the manufacturing and assembly process.

[0023] 4) The sensitive layer microstructure of the composite sensor of the present invention adopts a spiral structure similar to that of a cycad flower. The microstructure is designed as several micro-scale spirally arranged units, which can distinguish between positional compression and bending stress. Its structural design generates compression when subjected to pressure. When vertical pressure is applied, the spiral microstructure will undergo compressive deformation along its height direction (perpendicular to the substrate). This compression is mainly concentrated at the top. Due to the large height-to-width ratio of the structure (10:1), the compression causes a change in contact area, resulting in a change in resistance. When the sensor is subjected to bending stress, the spiral scales will undergo lateral displacement or rotation at the bending point, resulting in a change in the relative position between the scales. This change is different from the compression caused by vertical pressure. Instead, it causes tensile deformation on the inner and outer sides of the bending point. Due to the design characteristics of the spiral structure, the resistance change caused by bending stress is due to the spiral structure design characteristics.

[0024] 5) The composite sensor of the present invention uses a strain sensing mechanism to measure the bending angle of the entire finger and a sliding rheostat principle to confirm the bending of the interphalangeal joint. Through collaborative sensing, the hand motion capture system is simplified and the workload of back-end processing is reduced.

[0025] 6) The composite sensor of the present invention adds pads on both sides of the interphalangeal joint of the human finger to ensure good support when the sensor is long, thus ensuring the stability and durability of the sensor structure. After being stretched and deformed, the support pads return to their original shape in a short time to ensure the stable performance of the sensor during frequent use.

[0026] 7) The composite sensor of the present invention is filled with inert gas in the spacer layer, which effectively prevents oxidation of internal materials and circuits and extends the service life of the sensor. Attached Figure Description

[0027] Figure 1 is a front view of a wearable composite sensor structure for strain and positioning according to the present invention;

[0028] Figure 2 is a top view of a wearable composite sensor structure for strain and positioning according to the present invention;

[0029] Figure 3 is a side view of a wearable composite sensor structure for strain and positioning according to the present invention;

[0030] Figure 4 is a schematic diagram of the spiral microstructure of the imitation cycad flower of the present invention;

[0031] Figure 5 is a schematic diagram of the position positioning principle of a wearable composite sensor for strain and positioning according to the present invention;

[0032] Figure 6 is a schematic diagram of the bending stress of a wearable composite sensor for strain and positioning according to the present invention. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0034] In this embodiment, a wearable composite sensor for strain and positioning is provided, as shown in Figures 1, 2 and 3, including: a metal electrode layer, a sensitive layer, a non-conductive pad (3), an inert gas spacer layer (4), a first electrode (5), a non-conductive pad (6), a second electrode (9), a lead wire (10), an insulating package (11) and a collar (12).

[0035] The metal electrode layer, sensitive layer, non-conductive pad (3), inert gas spacer layer (4), first electrode (5), non-conductive pad (6), and second electrode (9) together constitute the position recognition module;

[0036] The metal electrode layer is composed of a metal coating (1) and a coating substrate (2), wherein the metal coating (1) is attached to the surface of the coating substrate (2);

[0037] The sensitive layer consists of a conductive sensitive material layer (7) and a microstructure substrate (8), wherein the conductive sensitive material layer (7) is attached to the surface of the microstructure substrate (8);

[0038] The metal film (1) is externally connected to the lead wire (10) as an output electrode;

[0039] The sensitive layer and the metal electrode layer are supported by a plurality of non-conductive pads (6), and filled with inert gas to form the inert gas spacer layer (4).

[0040] The first electrode (5) and the second electrode (9) are respectively connected to the two ends on the same side of the non-conductive pad (3);

[0041] The non-conductive pad (3) surrounds the periphery of the sensitive layer and the metal electrode layer, and one end with the first electrode (5) and the second electrode (9) is connected to the sensitive layer;

[0042] When the position recognition module is not subjected to external force, the sensitive layer and the metal electrode layer do not contact each other and do not generate a conductive path. When the sensitive layer is subjected to pressure from the interphalangeal joint of a finger through the collar (13), the sensitive layer at the pressure point passes through the inert gas spacer layer (4) and comes into contact with the metal electrode layer. The low resistance of the metal film plated (1) on the metal electrode layer comes into contact with the high resistance of the conductive sensitive material layer (7) on the sensitive layer. The first electrode and the output electrode form a conductive path and generate a position signal through the microstructure substrate (8).

[0043] The sensitive layer, the first electrode (5), and the second electrode (9) together form a strain sensing module;

[0044] The first electrode (5) and the second electrode (9) are bonded to both sides of the sensitive layer.

[0045] The first electrode (5) and the second electrode (9) are respectively connected to the lead wire (10) and serve as the input electrode and the second electrode (9) serves as the output electrode;

[0046] When the finger is bent, the strain sensing module transmits bending stress to the sensitive layer through the collar (13). When the sensitive layer is subjected to bending stress, the resistance between the first electrode (5) and the second electrode (9) changes, generating a strain signal.

[0047] The outer side of the insulating package (11) is connected to the collar (12); the insulating package (11) encloses the position identification module and the strain sensing module inside.

[0048] Preferably, the metal film plating (1) material is one of gold (Au), silver (Ag), and copper (Cu), preferably metallic copper (Cu);

[0049] The coating substrate (2) material can be selected from one of the following materials: polyimide (PI), polyester (PET), silicone, etc., preferably silicone; the coating substrate (2) material is coated with a layer of conductive metal material by means of physical vapor deposition, chemical vapor deposition, spraying, electroplating, etc., preferably physical vapor deposition.

[0050] Preferably, the conductive and sensitive material layer (7) can be one or more of metal nanowires, carbon nanotubes, graphene, and conductive rubber, with carbon nanotubes being the preferred material.

[0051] Preferably, as shown in Figure 4, the microstructure substrate (8) can be selected from one of polyimide (PI), polyester (PET), polyimide (PI), polyethylene (PE), silicone, and paper substrate, preferably silicone; its microstructure is one of imitation pine cone scale structure, imitation conch shell structure, double helical spring structure, and imitation cycad flower spiral microstructure, preferably imitation cycad flower spiral microstructure;

[0052] The spiral microstructure mimicking cycad flowers has a spiral angle of 20-45°; the diameter of the first layer is 50-100 micrometers, the diameter of the second layer is 100-150 micrometers, the diameter of the third layer is 100-150 micrometers, the diameter of the fourth layer is 200-250 micrometers, the layer height is 20-50 micrometers, and the pitch is 10-25 micrometers; preferably, the first layer has a diameter of 80 micrometers, a height of 20 micrometers, and a pitch of 15 micrometers; preferably, the second layer has a diameter of 120 micrometers, a height of 25 micrometers, and a pitch of 18 micrometers; preferably, the third layer has a diameter of 170 micrometers, a height of 30 micrometers, and a pitch of 20 micrometers; preferably, the fourth layer has a diameter of 220 micrometers, a height of 35 micrometers, and a pitch of 22 micrometers.

[0053] The spiral microstructure of the imitation cycad flower can be arranged in an alternating, gradient, or honeycomb pattern, with an alternating arrangement being preferred.

[0054] Preferably, the inert gas filling the inert gas spacer layer (4) can be one of nitrogen, helium and argon; the thickness of the inert gas spacer layer is 0.5~2 mm, preferably helium, and the thickness of the filling gas spacer is 2 mm.

[0055] Preferably, the non-conductive pad (3) can be selected from one of polytetrafluoroethylene, epoxy resin, polycarbonate, and polytetrafluoroethylene, with polytetrafluoroethylene being the most preferred.

[0056] Preferably, the non-conductive pad (6) can be selected from polyurethane (PU), thermoplastic elastomer, rubber, or foam silicone, with foam silicone being the most preferred.

[0057] Preferably, the thickness of the non-conductive pad (3) can be selected from 1.5 to 2.5 mm, preferably 2.5 mm.

[0058] Preferably, the non-conductive pad (6) can be 1-2 mm, preferably 2 mm.

[0059] The sensitive layer serves as both a high-resistance layer for positioning and a sensitive layer for bending stress sensing. The metal electrode layer serves both as a low-resistance layer for positioning sensing and as the output electrode for the third electrode.

[0060] In this embodiment, a method for fabricating a wearable composite sensor for strain and positioning recognition is provided, comprising:

[0061] 1) Preparation of silver nanowire dispersion: Silver nanowires were dispersed in deionized water (or ethanol, acetone, DMF, etc.) to prepare a reference concentration of 5 mg / mL (range 0.1-5 mg / mL). The dispersion was then subjected to ultrasonic oscillation at 50 kHz for 10 minutes to ensure uniform distribution of the silver nanowires.

[0062] 2) Preparation of the Sensitive Layer Silicone Substrate: Using 3D printing technology, a sensitive layer substrate mold was printed using aluminum as the substrate. The upper surface of the substrate was designed with a spiral microstructure mimicking the flower pattern of a cycad. The inside of the mold was coated with a silicone release agent to facilitate subsequent demolding. A high-precision sprayer was used to spray a dispersion of silver nanowires, followed by slow pouring of silicone into the mold from one side, allowing the silicone to gradually flow to the other side to reduce air bubble formation. The mold containing the silicone was placed on a vibration table; vibration helped to expel air bubbles. The mold was then cured at room temperature for 24 hours or in an oven at 80°C for 2 hours. After curing, the substrate was removed from the mold, and the surface was smoothed and excess material was removed.

[0063] 3) Electrode Connection for Sensitive Layer: Clean the surface with a lint-free cloth. Use a thin copper film as the electrode and evenly apply conductive adhesive to both sides of the sensitive layer. The adhesive layer thickness should be moderate to ensure good electrical contact. Align the electrode and place it on the adhesive-coated area, allowing it to dry naturally. Then, fix the lead wire to the bonding position and further secure it with conductive silver paste. Store the prepared sensitive layer in a clean storage box.

[0064] 4) Fabrication of the metal electrode layer:

[0065] 4-1) Silicone substrate preparation: The silicone substrate was cut using a laser cutter with a power setting of 20W, a cutting speed of 10 mm / s, and a gas flow rate of 3 L / min. After cutting, the cutting residue on the silicone substrate was removed.

[0066] 4-2) Metallization: Place the silicone substrate obtained in step 6-1 in a magnetron sputtering apparatus. Clean the copper target and set the distance between it and the silicone substrate to 10 cm. Use argon as the sputtering gas, with parameters set as follows: vacuum chamber pressure 5 x 10^-6 Torr, sputtering frequency 100 W, argon flow rate 50 sccm, and sputtering time 5 minutes. After sputtering, check the adhesion between the metal film and the silicone substrate to ensure there is no peeling.

[0067] 5) Lead bonding: A section of the metal electrode layer prepared in step

[0044] is bonded with conductive silver paste to the lead.

[0068] 6) Adhesive support pads: According to the experimental requirements, the prepared sensitive layer is attached to both sides of each finger joint with support pads (3 mm long, 3 mm wide, and 2 mm thick).

[0069] 7) Pre-fixing of insulating encapsulation: Adhere the lower surfaces of the sensitive layer and the metal electrode layer to the insulating encapsulation PET film, which is 110 mm long, 16 mm wide, and 0.5 mm thick. Leave appropriate dimensions in case of encapsulation failure, and then adhere the non-conductive gasket to the PET film.

[0070] 8) Sealing: Of the two pre-installed needles, one is an air inlet and the other is an air outlet. Connect the inert gas source to the air inlet and slowly open the gas flow valve to allow the inert gas to flow into the spacer layer, gradually expelling the air from the container. Maintain a certain gas flow rate and allow the gas to circulate within the container for a period of time to ensure complete air replacement. Then, remove both needles and seal the remaining holes with a clamp. Finally, use a 100°C hot air gun for sealing. After sealing, remove the clamp and trim off any excess sealing material.

[0071] When no external force is applied, as shown in Figure 1, the sensor remains stationary. When a certain pressure is applied, as shown in Figure 5, the sensor deforms, and the sensitive layer forms electrical contact with the metal electrode layer. Current flows in from the input electrode, through the pressing point, and then through the output electrode. Changes in the pressing position cause different changes in the current connected to the circuit. When the pressing position is close to the metal electrode layer, the resistance of the circuit decreases; conversely, when the pressing position is far from the right lead of the metal electrode layer, the resistance increases. This demonstrates that the sensor can sense and identify different pressing positions.

[0072] When the sensor is bent, as shown in Figure 6, the sensitive layer deforms under bending stress, causing a change in its resistance value.

[0073] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A wearable composite sensor for strain and positioning, characterized in that, include: Metal electrode layer, sensitive layer, non-conductive pad (3), inert gas spacer layer (4), first electrode (5), non-conductive pad (6), second electrode (9), lead wire (10), insulating encapsulation (11) and collar (12); The metal electrode layer, sensitive layer, non-conductive pad (3), inert gas spacer layer (4), first electrode (5), non-conductive pad (6), and second electrode (9) together constitute the position recognition module; The metal electrode layer is composed of a metal coating (1) and a coating substrate (2), wherein the metal coating (1) is attached to the surface of the coating substrate (2); The sensitive layer consists of a conductive sensitive material layer (7) and a microstructure substrate (8), wherein the conductive sensitive material layer (7) is attached to the surface of the microstructure substrate (8); The metal coating (1) is externally connected to the lead wire (10) as an output electrode; The sensitive layer and the metal electrode layer are supported by a plurality of non-conductive pads (6), and filled with inert gas to form the inert gas spacer layer (4). The first electrode (5) and the second electrode (9) are respectively connected to the two ends on the same side of the non-conductive pad (3); The non-conductive pad (3) surrounds the periphery of the sensitive layer and the metal electrode layer, and one end with the first electrode (5) and the second electrode (9) is connected to the sensitive layer; When the position recognition module is not subjected to external force, the sensitive layer and the metal electrode layer do not contact each other and do not generate a conductive path; when the sensitive layer is subjected to pressure from the interphalangeal joint of the finger through the collar (12), the sensitive layer at the pressure point passes through the inert gas spacer layer (4) and comes into contact with the metal electrode layer. The low resistance of the metal coating (1) on the metal electrode layer comes into contact with the high resistance of the conductive sensitive material layer (7) on the sensitive layer, and the first electrode and the output electrode form a conductive path and generate a position signal through the microstructure substrate (8); The sensitive layer, the first electrode (5), and the second electrode (9) together form a strain sensing module; The first electrode (5) and the second electrode (9) are bonded to both sides of the sensitive layer. The first electrode (5) is connected to the lead (10) and serves as the input electrode; the second electrode (9) is connected to the lead (10) and serves as the output electrode corresponding to the second electrode. When the finger is bent, the strain sensing module transmits bending stress to the sensitive layer through the collar (12). When the sensitive layer is subjected to bending stress, the resistance between the first electrode (5) and the second electrode (9) changes, generating a strain signal. The outer side of the insulating package (11) is connected to the collar (12); the insulating package (11) encloses the position identification module and the strain sensing module inside; The microstructure substrate is one of polyimide, polyester, polyethylene, silicone, or paper substrate, and its microstructure is one of pine cone scale structure, conch shell structure, double helical spring structure, or cycad flower spiral microstructure. Its microstructure is designed as several microscale spirally arranged units.

2. The wearable composite sensor for strain and positioning according to claim 1, characterized in that, The metal film plating (1) material is one of gold (Au), silver (Ag) and copper (Cu), preferably metallic copper (Cu); The coating substrate (2) material can be selected from one of the following materials: polyimide (PI), polyester (PET), silicone, etc., preferably silicone; the coating substrate (2) material is coated with a layer of conductive metal material by means of physical vapor deposition, chemical vapor deposition, spraying, electroplating, etc., preferably physical vapor deposition.

3. A wearable composite sensor for strain and positioning according to claim 1, characterized in that, The conductive and sensitive material layer (7) can be one or more of metal nanowires, carbon nanotubes, graphene, and conductive rubber, preferably carbon nanotubes.

4. A wearable composite sensor for strain and positioning according to claim 1, characterized in that, The microstructure substrate (8) can be selected from one of polyimide (PI), polyester (PET), polyimide (PI), polyethylene (PE), silicone, and paper substrate, preferably silicone; its microstructure is one of imitation pine cone scale structure, imitation conch shell structure, double helical spring structure, and imitation cycad flower spiral microstructure, preferably imitation cycad flower spiral microstructure; The spiral microstructure mimicking cycad flowers has a spiral angle of 20-45°; the diameter of the first layer is 50-100 micrometers, the diameter of the second layer is 100-150 micrometers, the diameter of the third layer is 100-150 micrometers, the diameter of the fourth layer is 200-250 micrometers, the layer height is 20-50 micrometers, and the pitch is 10-25 micrometers; preferably, the first layer has a diameter of 80 micrometers, a height of 20 micrometers, and a pitch of 15 micrometers; preferably, the second layer has a diameter of 120 micrometers, a height of 25 micrometers, and a pitch of 18 micrometers; preferably, the third layer has a diameter of 170 micrometers, a height of 30 micrometers, and a pitch of 20 micrometers; preferably, the fourth layer has a diameter of 220 micrometers, a height of 35 micrometers, and a pitch of 22 micrometers. The spiral microstructure of the imitation cycad flower can be arranged in an alternating, gradient, or honeycomb pattern, with an alternating arrangement being preferred.

5. A wearable composite sensor for strain and positioning according to claim 1, characterized in that, The inert gas filling the inert gas spacer layer (4) can be one of nitrogen, helium and argon; the thickness of the inert gas spacer layer is 0.5~2 mm, preferably helium, and the thickness of the filling gas spacer is 2 mm.

6. A wearable composite sensor for strain and positioning according to claim 1, characterized in that, The non-conductive pad (3) can be selected from one of polytetrafluoroethylene, epoxy resin, polycarbonate, and polytetrafluoroethylene, preferably polytetrafluoroethylene.

7. A wearable composite sensor for strain and positioning according to claim 1, characterized in that, The non-conductive pad (6) can be selected from polyurethane (PU), thermoplastic elastomer, rubber, or foam silicone, preferably foam silicone.

8. A wearable composite sensor for strain and positioning according to claim 1, characterized in that, The thickness of the non-conductive pad (3) can be selected from 1.5 to 2.5 mm, preferably 2.5 mm.

9. A wearable composite sensor for strain and positioning according to claim 1, characterized in that, The non-conductive pad (6) can be 1-2mm, preferably 2mm.

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