High-integration-level intelligent interaction system design based on triboelectric sensor array

Abstract

The invention discloses a wearable triboelectric sensor array based on flexible circuit integration and a preparation method thereof. According to the sensor, a nylon film and an Ecoflex film are adopted as a positive friction layer and a negative friction layer, and a nano conical array structure is constructed on the nylon surface through AAO template hot press molding, so that the effective contact area is remarkably increased, and the charge output performance is improved. The sensing array is integrated on a flexible printed circuit board (FPC), and an amplifying circuit, a filter circuit and a micro-control unit are arranged in the FPC, so that local acquisition and wireless transmission of signals are realized. The friction layer and the bonding pad are electrically connected through the conductive silver paste, and the distance between the positive friction layer and the negative friction layer is adjusted through the sponge spacing layer so as to adapt to wrist structures of different wearers. The system carries out action recognition by capturing differential voltage waveforms and peak value characteristics triggered by wrist actions in real time. According to the design, the structure is compact, the flexibility is good, complex wiring and signal loss caused by traditional multi-wire connection are reduced, and the wearable comfort, the signal stability and the system integration degree are remarkably improved.

Description

Technical Field

[0001] This invention belongs to the technical field of flexible sensors and novel human-computer interaction methods. It is a human motion signal sensing system, method and application based on triboelectric sensors. Background Technology

[0002] Triboelectricity is a common phenomenon of contact charge separation: when two different materials rub against each other or undergo a contact-separation process, charge transfer occurs at the interface, forming detectable induced charges on the surface. The amount of charge generated is mainly related to the difference in electronegativity of the contact materials and the interface contact state, and can produce corresponding electrical responses to external mechanical stimuli (such as pressure, sliding, or vibration).

[0003] Triboelectric sensors can directly convert mechanical energy into electrical signals without an external power source, enabling self-powered tactile detection. Compared with traditional resistive, capacitive, or piezoelectric sensors, triboelectric sensors have advantages such as simple structure, relatively user-friendly fabrication process, ease of arraying and integration, and good long-term operational stability. Therefore, they have broad application potential in wearable devices, environmental sensing, and human-computer interaction scenarios.

[0004] Despite the advantages of triboelectric sensors in signal generation mechanisms, they still face severe system-level challenges in the process of moving towards practical wearable applications, mainly in the following two aspects: (1) Current triboelectric sensor systems are often limited by physical wiring. Since each sensing unit usually requires an independent signal output line, the number of wires will increase exponentially as sensors develop towards higher resolution and multi-array. (2) Complex wiring and transmission methods greatly reduce the wearability and reliability of the device in dynamic motion monitoring. Summary of the Invention

[0005] The present invention aims to solve the above problems. Based on the above background technology, the present invention realizes a wearable triboelectric sensor array based on flexible circuit integration and its preparation method, and develops a complete peripheral circuit acquisition output and interaction system.

[0006] To achieve the above objectives, the present invention discloses the following technical solution.

[0007] The first aspect of this disclosure provides a method for fabricating a high-performance triboelectric sensor, comprising the following steps:

[0008] Nylon and Ecoflex are selected for use together to form the friction pair, and the nylon surface is microstructured to further increase the surface charge density.

[0009] Anodized aluminum oxide (AAO) templates were selected, with a hole spacing of approximately 450 nm and a hole depth of approximately 400 nm. The template hole diameter / depth ratio met the required microstructure geometry.

[0010] A conical array structure was prepared by dissolving nylon 6 in formic acid, vacuum drying it into a film, stacking it with an AAO template, and hot-pressing it at 300°C, thereby plastically filling the nylon surface.

[0011] The sample is immersed in sodium hydroxide solution to dissolve the template, and after ultrasonic cleaning, a nylon film with a high specific surface area microstructure can be obtained.

[0012] The second aspect of this disclosure provides a method for fabricating a flexible FPC that reduces signal loss caused by traditional external lines, comprising the following steps:

[0013] When designing the FPC circuit board, five pads are reserved at the analog signal receiving point at the front end of the operational amplifier for integration with the triboelectric sensor array.

[0014] The triboelectric sensor is directly bonded and fixed to the receiving pad of the flexible printed circuit board (FPC) wristband; the FPC pad for receiving signals is bonded to the nylon friction layer of the triboelectric sensor by conductive silver paste to form an electrical connection, thereby realizing low impedance signal transmission and improving the noise immunity and reliability of signal acquisition.

[0015] Furthermore, the triboelectric sensor is combined with a flexible printed circuit board (FPC). The FPC integrates a near-end low-noise amplifier circuit and a filter circuit based on MCP6002T. The amplified and filtered signal is transmitted to the ADC module of ADS1115 on the FPC, and then transmitted to the microcontroller unit ESP32 via the IIC transmission protocol.

[0016] After the above steps, the ESP32 uses its wireless WIFI function to wirelessly transmit the collected signals or digitally processed data packets to an external receiving terminal, thereby reducing external signal cables, improving wearability, and ensuring real-time signal transmission.

[0017] This disclosure provides a highly integrated intelligent interaction system in a third aspect, comprising the following technical solutions:

[0018] Based on the high surface area triboelectric sensor array of the first aspect, the system adopts a strong signal output and combines an integrated FPC solution to replace the traditional complex wiring. While simplifying the structure and reducing losses, it ensures the high reliability and excellent wearable sensing performance of the device.

[0019] By utilizing the integrated FPC circuit of the second aspect, wrist movement features are captured through a triboelectric sensor array, and differential electrical signals are mapped into specific commands through pattern recognition, thereby realizing wireless interactive control of remote devices.

[0020] In this invention, a micro-nano array is constructed on the surface of nylon using an AAO template hot-pressing process to improve the self-powered sensing performance. An integrated FPC flexible circuit scheme is adopted, and conductive silver paste is used to achieve a direct low-impedance connection between the sensing array and the near-end conditioning circuit. This effectively solves the problems of complex wiring and signal loss in traditional wearable devices, and constructs a highly integrated human-computer interaction system that integrates signal acquisition, pattern recognition and wireless communication. Attached Figure Description

[0021] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute a limitation thereof.

[0022] Figure 1 This describes the charge transfer working principle of the triboelectric sensor in Embodiment 1 of this disclosure;

[0023] Figure 2 This is a schematic diagram of the surface structure of the nylon film formed by hot pressing with an AAO template in Embodiment 1 of this disclosure;

[0024] Figure 3 This is a SEM image of the inclined plane of the micro / nano structure on the surface of the nylon film in Embodiment 1 of this disclosure;

[0025] Figure 4 This is a cross-sectional SEM image of the micro / nano structure on the surface of the nylon film in Embodiment 1 of this disclosure;

[0026] Figure 5 This is a schematic diagram of the triboelectric sensor structure in Embodiment 1 of this disclosure;

[0027] Figure 6 This is a comparison diagram of the voltage performance of the triboelectric sensor before and after constructing the micro / nano structure in Embodiment 1 of this disclosure;

[0028] Figure 7 This is a diagram illustrating the non-contact performance of the triboelectric sensor in Embodiment 1 of this disclosure;

[0029] Figure 8 This is a cyclic performance diagram of the triboelectric sensor in Embodiment 1 of this disclosure;

[0030] Figure 9 This is a graph showing the pressure sensitivity performance of the triboelectric sensor in Embodiment 1 of this disclosure;

[0031] Figure 10 This is a diagram of the FPC circuit architecture and data transmission in Embodiment 2 of this disclosure;

[0032] Figure 11 This is a schematic diagram of the working principle of the FPC integrated unit in Embodiment 2 of this disclosure;

[0033] Figure 12 This is a voltage performance diagram of the FPC under different degrees of bending in Embodiment 2 of this disclosure;

[0034] Figure 13 This is a schematic diagram of the wearing state interaction in Embodiment 3 of this disclosure;

[0035] Figure 14 This is a schematic diagram of the force distribution of different signals in Embodiment 3 of this disclosure; Specific implementation methods

[0036] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0037] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0038] It should be noted that the terminology used herein is for descriptive purposes only and is not intended to limit the exemplary embodiments according to this disclosure. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof. It should be noted that, without conflict, the various embodiments and features within those embodiments can be combined with each other. The embodiments will now be described in detail with reference to the accompanying drawings.

[0039] When there are a large number of array sensors, a corresponding number of signal leads are required, leading to a complex overall structure. Multi-wire connections increase the assembly difficulty between the circuit board and the sensors, hindering miniaturization and flexible design. Excessive signal lines not only affect wearing comfort but are also prone to breakage or interference in wearable applications, resulting in insufficient reliability. Therefore, the application of existing triboelectric sensor arrays in wearable electronic devices is severely limited, necessitating a solution with simplified structure, efficient signal transmission, and suitability for flexible integration.

[0040] The purpose of this invention is to overcome the shortcomings of existing sensor arrays, such as complex wiring that is unsuitable for wearable applications, and to propose a triboelectric sensor array and its signal transmission method. By directly integrating sensor units and signal processing modules on a flexible circuit board, the number of external connection lines is reduced, enabling centralized acquisition and transmission of array signals. This invention not only simplifies the device structure and improves system reliability, but also significantly enhances comfort and practicality in wearable conditions.

[0041] Example 1

[0042] In one or more of the technical solutions disclosed in the embodiments, the method based on the triboelectric sensor array and the signal transmission method thereof includes: fabrication of flexible triboelectric sensors, wearable flexible FPCB circuit board, signal acquisition and transmission.

[0043] In this embodiment, the triboelectric sensor array uses Ecoflex film and nylon film as positive and negative friction layers, respectively. After repeatedly comparing the differences in electronegativity and mechanical properties of different friction materials, it was determined that the combination of Ecoflex and nylon film can generate significant charge transfer under external mechanical stimulation, exhibiting higher electrical signal output intensity. The charge transfer principle is as follows: Figure 1 As shown. Furthermore, this material combination exhibits excellent structural stability during long-term use, with a strong bond between the friction layers, making it less prone to peeling or performance degradation, thus ensuring the reliability of the sensor array under wearable conditions. Simultaneously, both Ecoflex and the nylon membrane are non-toxic and non-irritating to human skin, ensuring good safety in direct skin contact.

[0044] The Ecoflex film was prepared by mixing Ecoflex component A and component B at a mass ratio of 1:1, using approximately 30g of the mixture, and stirring thoroughly at room temperature until homogeneous. The homogeneous Ecoflex solution was then uniformly coated onto the surface of a 20cm × 20cm polyimide (PI) film. The PI film was a commercially available finished product with good mechanical and heat resistance properties, making it suitable as a substrate layer for triboelectric sensor arrays.

[0045] In a further step, the coated sample was placed horizontally in a vacuum drying oven and maintained under vacuum for approximately 4 hours. This vacuum treatment effectively eliminates microbubbles generated during Ecoflex stirring, preventing defects in the film formation. It also allows the Ecoflex liquid to spread more evenly on the PI film surface, improving the density and smoothness of the friction layer. After this treatment, the resulting Ecoflex layer is tightly bonded to the PI film, providing a stable and reliable material basis for the subsequent construction of a triboelectric sensor array.

[0046] The nylon membrane was prepared as follows: Nylon 6 particles were added to formic acid solvent at a mass ratio of 1:6. The resulting mixture was placed on a magnetic stirrer and stirred continuously for 2 hours at approximately 60°C to ensure that the nylon 6 particles were fully dissolved in the formic acid, forming a transparent and homogeneous polymer solution. After the solution was prepared, the uniformly mixed nylon 6 solution was slowly poured into a 10 cm diameter petri dish, allowing the solution to spread evenly on the bottom of the dish. The petri dish was then placed horizontally in a vacuum drying oven at approximately 50°C. The oven was maintained under vacuum heating for 3 hours to allow the formic acid solvent to fully evaporate, thus avoiding the influence of residual solvent on the membrane performance.

[0047] After the formic acid has completely evaporated, remove the petri dish from the vacuum drying oven and allow it to cool naturally to room temperature. At this point, a slight separation of the film from the inner wall of the petri dish can be observed. The intact nylon film can then be peeled off with tweezers. The resulting film has a uniform thickness, a smooth surface without bubbles, and good flexibility and mechanical strength.

[0048] In this embodiment, the AAO (anodic aluminum oxide) template can effectively enhance sensor performance. This template has a periodic array of micropores with a spacing of approximately 450 nm and a depth of approximately 400 nm. The microstructure surface of the template has one side with downward-facing V-shaped openings. With the microstructure surface of the AAO template facing upwards, the construction steps are as follows:

[0049] Step 1: Cut the flat nylon film obtained in the previous steps of this example into a 1.5 cm × 1.5 cm sample. Prepare a 3 cm × 3 cm glass slide as the carrier substrate for the hot press. Place the 3 cm × 3 cm glass slide as a base on the lower heating plane or worktable of the hot press; place the AAO template (microstructure side facing up) on the glass slide; stack the cut 1.5 cm × 1.5 cm nylon film on the AAO template (side to be constructed of micro / nano structures facing down in contact with the template); finally, cover the top layer with another 3 cm × 3 cm glass slide of the same size to ensure uniform force and prevent the sample from adhering to the indenter.

[0050] Step 2: Heat the hot press to approximately 300°C. Once the hot press reaches the predetermined temperature, rotate the handle or activate the mechanical device to apply downward pressure to the upper glass substrate. This ensures sufficient clamping force between the heated surface of the hot press and the upper glass layer, allowing the AAO template to come into close contact with the nylon film and ensuring that the nylon can fully flow and fill the template microstructure under heating conditions. The preferred heating and pressurization time is approximately 15 minutes to ensure that the nylon film becomes flowable under heating and fully fills the V-shaped pores of the AAO template. After maintaining the heating and pressurization conditions for the predetermined time, turn off the heating and allow the sample to slowly cool to room temperature while maintaining pressure. This facilitates nylon curing and fixation of the mold filling morphology. Once the temperature has dropped to room temperature or a safe operating temperature range, release the clamping device and remove the sample.

[0051] Step 3: Carefully immerse the remaining AAO / nylon / glass composite in a pre-prepared sodium hydroxide (NaOH) solution for template removal. To protect the formed microstructure, a complete immersion method rather than mechanical peeling should be used. Immerse the composite in the NaOH solution for approximately 8 hours to allow the aluminum component in the AAO template to fully react chemically with the alkaline solution and dissolve, thereby completely removing the template. After template removal and preliminary neutralization / rinsing, remove the microstructured nylon film from deionized water and rinse it multiple times under running deionized water to remove as much residual NaOH and dissolution products as possible.

[0052] Step 4: After immersing the nylon film in deionized water, ultrasonically clean it for 10 minutes using a low-power, short-time circulation mode to thoroughly remove residual impurities while protecting the integrity of the micro / nano structure. After ultrasonic treatment, rinse the sample thoroughly again with a large amount of deionized water, then remove the film and allow it to dry at low temperature in a dust-free environment. The resulting 3D structure of the nylon film is shown in the figure. Figure 2 As shown.

[0053] In this embodiment, the micro / nano structure constructed in the above steps can be visualized using an optical microscope or a scanning electron microscope (SEM), such as... Figure 3 and Figure 4 The morphology and integrity are inspected using methods such as surface profilometers to confirm that the microstructure array is intact, free of obvious residual particles, and that the surface is clean. The resulting clean microstructured nylon film is obtained through the above treatment.

[0054] The structure of the triboelectric sensor in this embodiment is shown below. Figure 5 As shown, the triboelectric sensor, after micro / nano-structuring, exhibits a significant improvement in output voltage performance compared to its original state. Figure 6 As shown, this demonstrates the significant effect of surface morphology modulation on charge density enhancement. Furthermore, the sensor exhibits excellent electrostatic induction capabilities even in non-contact mode. Figure 7 As shown, it can sensitively capture electrical signals generated by human mechanical movement, providing reliable data support for human-computer interaction.

[0055] Regarding long-term operational reliability, the sensor in this embodiment exhibits excellent cyclic performance, such as... Figure 8 As shown, after thousands of cyclic load tests, the output signal amplitude did not show significant attenuation, demonstrating that the nylon and Ecoflex friction layer materials possess excellent mechanical durability and chemical stability. Meanwhile, the pressure sensitivity test curve is shown in... Figure 9 As shown, the sensor output voltage exhibits a good linear relationship and high sensitivity with the change of applied pressure, and can accurately distinguish minute pressure fluctuations, ensuring high-precision feature extraction in wrist motion recognition and flexible tactile sensing applications.

[0056] Example 2

[0057] Based on Embodiment 1, this embodiment provides a method for fabricating an integrated acquisition circuit as described in Embodiment 1. The signal acquisition unit uses a flexible printed circuit board (FPC) as a carrier platform. The FPC has a two-layer structure and integrates functional components such as an amplifier circuit, a filter circuit, a signal transmission module, and a microcontroller (MCU). Its circuit architecture is as follows: Figure 10 As shown.

[0058] Based on the above structure, to obtain a good triboelectric signal, an amplifier circuit is used to process the weak electrical signal from the triboelectric sensing unit using the primary gain of an MCP6002T operational amplifier. The dual-T filter circuit is used to suppress 50Hz power frequency interference and high-frequency noise. After the amplifier circuit transmits the signal to the ADS1115 acquisition module, it converts it into an IIC digital signal. The microcontroller receives the IIC signal and is responsible for sending the processed data to an external terminal through the signal transmission module.

[0059] To adapt to wearable scenarios, five conductive pads (hereinafter referred to as "collection pads") with a diameter of about 15 mm are reserved under the flexible circuit board. The five collection pads are evenly distributed on the flexible board surface so that they can collect the friction electrical signals of different positions on the wrist when worn on the wrist or similar ring-shaped parts. Figure 11 The working principle of the FPC integrated unit was demonstrated, and the voltage amplitude of the triboelectric sensor under different degrees of deformation was shown, such as... Figure 12 As shown.

[0060] Regarding the electrical connection between the aforementioned microstructured nylon film and the acquisition pads, this embodiment uses high-viscosity conductive silver paste for surface bonding and conductive connection.

[0061] The specific operation involves cutting the microstructured, cleaned, and dried nylon film into the desired shape (in this embodiment, it is cut into a circular sample with a diameter of approximately 15 cm), and aligning the nylon film with the FPC's acquisition pads at a predetermined position. The specific steps are as follows:

[0062] Step 1: Apply conductive silver paste to the surface of the pad by dotting or brushing, and then attach a nylon film to the surface of the pad coated with conductive silver paste, so that the conductive silver paste forms a continuous conductive interface between the nylon film and the pad.

[0063] Step 2: After bonding, place the assembly in an oven and heat-cur it at approximately 60°C to promote the evaporation of the conductive silver paste solvent and the formation of the conductive filler network structure, thereby obtaining a stable and low-impedance electrical connection. After curing, the nylon film can achieve a strong mechanical bond and reliable electrical connection with the flexible pad, ensuring that the triboelectric signal can be smoothly transmitted to the amplification circuit for subsequent processing.

[0064] Step 3: After completing the conductive bonding and curing of the nylon film and the FPC acquisition pads, in order to ensure that the negative friction layer (Ecoflex / PI composite layer) and the nylon positive friction layer maintain a stable interval during wear and have a good stress buffering effect during bending deformation, this embodiment attaches elastic buffer blocks to both sides of each acquisition pad; and attaches a rectangular sponge to both sides of each pad, the sponge being approximately 20 mm long, 5 mm wide, and 5 mm high, and using 3M double-sided tape to fix the sponge to the surface of the flexible board;

[0065] Step 4: Cut the PI / Ecoflex composite film, which has been uniformly coated with Ecoflex on the PI film substrate, into strips approximately 2 cm wide and 3-4 cm long. These strips will serve as the negative friction layer corresponding to each sampling pad. Before fixing the PI / Ecoflex strips onto the sponge, remove the Ecoflex coating from the area to be bonded to ensure direct adhesion between the PI film and the sponge substrate.

[0066] Specifically, in this embodiment, the length of the PI / Ecoflex strip can be customized according to the wearer's wrist circumference and the actual distribution of the pads on the wrist, and adjusted according to the different local bending radii of each sampling point when different wearers wear the flexible FPC.

[0067] Example 3

[0068] Based on Embodiment 2, this embodiment provides an interactive process based on changes in wrist muscles, wherein the aforementioned FPC serves as a device for sensing changes in muscle signals.

[0069] Its working principle is as follows: when the wrist is worn, different movements (such as flexion, extension, rotation, lifting, or lateral swing) result in varying stress distributions and bending amplitudes at different locations on the wrist surface, causing differences in relative displacement between the various sensing units in the array. Since the triboelectric sensing unit operates on a contact-separation model, its output voltage and current are closely related to the contact area, pressure, and contact speed. Therefore, under different movement conditions, the fluctuation patterns, amplitudes, and pulse morphologies of the electrical signals generated by each sensing unit show significant differences. A schematic diagram of the worn state is shown below. Figure 13 As shown.

[0070] Furthermore, this invention utilizes the differentiated characteristics of signal waveforms, peak distributions, and durations exhibited by the aforementioned triboelectric sensor array under different wrist movements to achieve remote control functionality based on motion recognition. By performing pattern recognition analysis on the electrical signal characteristics caused by different movements using the real-time output signals of the five sensing units, specific movements can be mapped to specific control commands.

[0071] In this example, the wearer can wirelessly control the remotely operated vehicle through natural gestures or wrist movements. The force distribution of the FPC under different gestures is as follows: Figure 14 As shown, specifically:

[0072] When the wrist tilts forward or bends, the amplitude of the output signal from the front sensing unit in the triboelectric array increases significantly. After recognizing this signal pattern, the MCU issues a "carriage forward" control command. When the wrist bends backward, the output of the rear sensing unit increases, corresponding to the "carriage backward" action. When the wrist rotates to the left or right, the output waveform of the left or right sensing unit shows a peak shift, corresponding to the "carriage turn left" and "carriage turn right" control commands, respectively.

[0073] In summary, this invention proposes a simplified, stable, and wearable triboelectric sensor array system by integrating triboelectric sensing units, signal acquisition circuits, and a wireless transmission module on a flexible substrate. The sensor uses a nylon film and an Ecoflex film to form positive and negative friction layers, and utilizes an AAO template for hot-pressing to construct a nanoscale conical array structure on the nylon surface, significantly increasing the frictional contact area and improving charge density and signal output strength. The array is integrated based on a flexible FPC circuit, which incorporates amplification, filtering, and signal processing circuits. Reliable conductive connection between the friction layers and the circuitry is achieved through conductive silver paste, effectively reducing the complexity and signal loss caused by multi-wire connections. The five independent sensing units in the array can simultaneously acquire mechanical signal changes from different parts of the wrist, enabling the identification of different wrist movements and remote control of unmanned vehicles such as forward, backward, and steering via a microcontroller unit. This invention offers advantages such as structural flexibility, stable signal, low power consumption, and good wearability, and can be widely applied in smart wearable devices, motion monitoring, and human-computer interaction.

[0074] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0075] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A highly integrated intelligent interactive system based on a triboelectric sensor array. Its features include: The triboelectric sensor is composed of positive and negative friction layers, five sensor arrays, a flexible FPC circuit board integrating acquisition and processing circuits, and a sensor array signal recognition gesture system.

2. The method for preparing positive and negative friction layers as described in claim 1, Its features include the use of specific materials as the friction layer material, including: Uniform Ecoflex films were prepared by methods such as stirring, coating, and vacuum drying. A uniform nylon film was prepared by mixing the solution in proportion, stirring, and vacuum drying.

3. The method for preparing the triboelectric sensor friction layer as described in claim 2, characterized in that an anodic aluminum oxide (AAO) template is used, one side of which is a V-shaped micropore array with a pore spacing of about 450 nm and a pore depth of about 400 nm, as a template for replicating the microstructure of nylon surface.

4. The method for preparing the micro / nano structure on the surface of the friction layer as described in claim 3, characterized in that... The process of fabricating micro / nano structures on the surface of nylon films using hot pressing includes the following steps: Cut the nylon film into squares with sides of 1.5 cm, stack them with the AAO template, and sandwich them between two glass plates; The nylon is heated to 300°C and pressure is applied in a hot press to fully fill the micropores of the template and form a microcone array structure. After hot pressing and cooling, the AAO / nylon composite was immersed in a 5% NaOH solution for about 8 hours. A clean microstructured nylon membrane was obtained by dissolving the aluminum template, washing, removing impurities with low-power ultrasonication, and drying.

5. The FPC flexible circuit board as described in claim 1, characterized in that: It adopts a dual-layer structure, integrating amplification, filtering, signal processing and wireless transmission circuits; Five 15 mm diameter acquisition pads are reserved at the bottom of the flexible circuit board for signal acquisition at different locations.

6. The method of combining the triboelectric sensor array with the FPC flexible circuit board as described in claims 1-5, characterized in that, The direct electrical connection between the friction layer and the FPC circuit board includes the following steps: The nylon film was cut into a circle with a diameter of 15 cm, and the side without micro-nano structures was connected to the FPC pads. The nylon film is bonded to the FPC pads using conductive silver paste, and then cured by heating at approximately 60°C. After curing, a stable and low-impedance electrical connection is obtained.

7. The method of combining the triboelectric sensor array with the FPC flexible circuit board as described in claims 1-6, characterized in that, The fabrication process of a triboelectric sensor includes the following steps: 5mm thick sponge blocks are attached to both sides of each pad to provide support and adjust the spacing; Use 3M adhesive to fix the PI / Ecoflex strip to the sponge and position it above the nylon film; When worn around the wrist, there is a pre-set gap of about 3 mm between the positive and negative friction layers of each sensing unit.

8. The bonding method as described in claim 7, characterized in that, Using five sensors, key points around the wrist circumference can be covered in a ring. Different movements will cause the voltage of the triboelectric sensor to produce different amplitudes, thus finely distinguishing different hand gestures.

9. The sensor array signal recognition gesture system as described in claim 1, characterized in that, Based on the WiFi function of the FPC's main control chip ESP32, the real-time dynamic voltage values ​​of the sensor array are transmitted to the outside. At the same time, the gesture type is identified according to the difference in voltage values ​​to complete the control of the unmanned vehicle.

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