Radiation-resistant reinforced capacitive flexible tactile sensor and preparation method and application thereof

Abstract

The invention relates to an anti-radiation reinforced capacitive flexible touch sensor and a preparation method and application thereof, and belongs to the technical field of sensors. The radiation-proof reinforced capacitive flexible touch sensor comprises a first protective layer, a first packaging layer, a first shielding layer, a sensitive layer, a second packaging layer and a second protective layer which are sequentially arranged from bottom to top. Layered progressive design is adopted, and a complete technical chain is formed from material innovation to system integration.

Description

Technical Field

[0001] This application relates to the field of sensor technology, and in particular to a radiation-hardened capacitive flexible tactile sensor, its fabrication method, and its application. Background Technology

[0002] Flexible tactile sensors, as one of the core components in the fields of industrial, military and special robots, integrate cutting-edge technologies from multiple disciplines such as flexible electronics, device physics and advanced materials, and show broad application prospects in aerospace missions, smart wearables, health monitoring, electronic skin and industrial robots.

[0003] With the increasing number and extended lifespan of spacecraft such as satellites, spaceships, and space stations, the demand for space crawling robots in spacecraft maintenance and repair is growing. When performing related control tasks, space robots urgently need distributed, highly sensitive, and large-range tactile force sensing capabilities at contact interfaces to accurately acquire key interface information such as contact mechanical properties, macro- and micro-morphological features, and motion states, providing refined contact state support for the generation of highly adaptive control strategies. The only way for crawling robots to acquire tactile information is through flexible tactile sensors mounted on their robotic arms. However, existing flexible tactile sensors cannot be effectively applied. On the one hand, various forms of radiation in outer space can cause structural, electrical, and thermal damage to the sensitive layer materials of flexible tactile sensors. Furthermore, cosmic ray radiation is mainly divided into non-ionizing and ionizing radiation. Non-ionizing radiation mainly includes ultraviolet light, visible light, infrared light, and microwaves, which have significant thermal effects, especially when acting on materials such as metals, where the resulting temperature changes can severely interfere with the signal stability of the sensor. Ionizing radiation has higher energy, such as mid-to-high frequency ultraviolet rays, X-rays, gamma rays, as well as alpha particles, beta particles, protons, neutrons, etc., which can damage the chemical bond structure and even the atomic structure of the electrodes and even the sensitive layer, causing irreversible damage or even permanent failure of the sensor.

[0004] Space contact processes are characterized by poor controllability and high contact intensity, requiring tactile sensors with larger ranges. Furthermore, the extreme space environment—including high vacuum, wide temperature range, and intense radiation—places extremely high demands on the sensor's stability across the entire temperature range, vacuum adaptability, and radiation resistance. Faced with the sensing challenges posed by the heterogeneity of spacecraft surface materials and the multifunctional components, existing tactile measurement methods based on normal or point contact struggle to comprehensively acquire inherent state information such as shape and material properties during the contact process, as well as dynamic changes such as sliding and relative pose, severely limiting the generalization ability to manipulate unstructured objects.

[0005] The lack of research on radiation-resistant materials for flexible tactile sensors means that existing flexible tactile sensors cannot meet the radiation protection requirements of space crawling robots. To date, neither domestically nor internationally, there are any designs that combine flexible tactile sensors with radiation-resistant materials and structures, nor are there any related patents published, which greatly hinders the application of sensors in on-orbit servicing and maintenance of spacecraft.

[0006] Therefore, there is an urgent need to develop array-type tactile sensing technology with high precision, large range, high sensitivity and high linearity to provide rich and accurate spatial and frequency domain tactile information for on-orbit crawling and fine operation. Summary of the Invention

[0007] In view of this, this application provides a radiation-hardened capacitive flexible tactile sensor, its preparation method and application, which can effectively overcome the defects of the prior art.

[0008] The first aspect of this application provides a radiation-hardened capacitive flexible tactile sensor, comprising, from bottom to top, a first protective layer, a first encapsulation layer, a first shielding layer, a sensitive layer, a second encapsulation layer, and a second protective layer.

[0009] Preferably, the radiation-hardened capacitive flexible tactile sensor includes, from bottom to top, a first protective layer, a first encapsulation layer, a first shielding layer, a sensitive layer, a second shielding layer, a second encapsulation layer, and a second protective layer.

[0010] Preferably, the material of the first or second shielding layer is: the surface layer has a density of 2.77 g / cm³. 3 The nano-mica sheets are arranged in parallel and stacked in an alternating manner to form a structure in which the nano-mica sheets are arranged in parallel and stacked in an alternating manner; the bottom layer uses dynamically covalently cross-linked ETTPBAT elastomer as the matrix, and hydrogen bond-epoxy interpenetrating network is formed with tannic acid phenolic hydroxyl groups and epoxidized soybean oil.

[0011] Preferably, the sensitive layer material is: tellurium nanowire / PEDOT:PSS composite thermoelectric gel with dynamic disulfide bond self-healing network; an ion conduction path with a highly interconnected three-dimensional network structure is constructed using tellurium nanowires, and the three-dimensional network is formed by the self-assembly of tellurium nanowires, with a large number of nanoscale pores inside the network, and a dynamic disulfide bond SS topology network is introduced; the tellurium nanowire / PEDOT:PSS composite material is prepared into a polyelectrolyte elastomer micro pyramid array structure using soft photolithography, wherein the pyramid array structure is a uniformly arranged quadrangular pyramid-shaped microstructure with a height of 10 micrometers, a base width of 10 micrometers, and a height angle of 52°.

[0012] Preferably, the material of the first or second encapsulation layer is specifically: based on polysulfone or fluorosilicone gradient heterogeneous protection technology, a multilayer structure is constructed in which the outer layer is formed by a dense cross-linked network of polysulfone-doped mica sheets, and the inner layer is formed by dynamically cross-linked fluorosilicone with modulus adjusted by PDMS-urea bonds; the outer layer is formed by a dense cross-linked network of polysulfone-doped mica sheets, and the inner layer is formed by dynamically cross-linked fluorosilicone with modulus adjusted by PDMS-urea bonds; nano-mica constructs a micro-nano secondary superhydrophobic structure, and the interlayer is formed by multiple bonds between the catechol / amine groups of polydopamine coupling agent and the polysulfone sulfonic acid groups and fluorosilicone silanol groups.

[0013] A second aspect of this application also provides a method for fabricating the above-mentioned radiation-hardened capacitive flexible tactile sensor, comprising the following steps:

[0014] S1. Mica sheets are plasma-cleaned to remove surface impurities and enhance activity; then dispersed in anhydrous ethanol and ultrasonically treated to form a uniform suspension; ETTPBAT is mixed with epoxidized soybean oil, a crosslinking agent is added, and the mixture is stirred to form a self-healing elastomer; the nano-mica sheet suspension is mixed with the ETTPBAT matrix, and the mixture is injected into a porous mold using a vacuum filtration method and filtered; the second layer of mica sheets is rotated and stacked using a mechanical transfer method to obtain a shielding layer;

[0015] S2, TeCl4, and Na2SeO3 solutions were mixed, a stabilizer was added, and the mixture was reacted. The nanowires were collected by centrifugation. PEDOT:PSS solution was mixed with tellurium nanowires, a dispersant and dithiothreitol (DTT) were added, and a reversible SS bond topological network was formed through a redox reaction. After stirring, a composite gel was obtained. A pyramid array was formed on a silicon substrate by laser direct writing, and plasma treatment was used to enhance hydrophilicity. The composite gel was injected into a template and cured by ultraviolet light to form a microcavity structure, thus obtaining a sensitive layer.

[0016] S3. Polyarylsulfone is dissolved in a solvent and mixed with nano-mica sheets, then ultrasonically dispersed. The solution is coated onto a polytetrafluoroethylene film, dried, and then peeled off to form a dense layer. Fluorosilicone prepolymer is mixed with PDMS-urea bonds, and a catalyst is added. Subsequently, a dynamic cross-linked network is formed by hot pressing. Finally, after coating with a polydopamine coupling agent, a micro-nano superhydrophobic structure is constructed by plasma treatment to obtain the encapsulation layer.

[0017] S4. Cut the lead plate to the target size and polish the surface; remove surface oxides by chemical cleaning, ultrasonic cleaning, and dry for later use; perform plasma cleaning on the tantalum foil to remove surface contaminants and activate the surface; deposit a Ti transition layer on the surface; mix borosilicate-based nanopowder with organic binder polyurethane, ball mill to form a uniform slurry; load the slurry into a vacuum plasma spraying system, and spray the powder onto the tantalum foil surface through plasma; after spraying, the sample is cured to remove organic solvents and obtain a protective layer;

[0018] S5. The first protective layer, the first encapsulation layer, the first shielding layer, the sensitive layer, the second encapsulation layer and the second protective layer, which are arranged from bottom to top, are assembled. Each layer is bonded with epoxy resin. The electrodes are made of Cu metal coated with Au layer, and the leads are generally copper wires. The electrodes above and below the sensitive layer are led out for signal transmission. A radiation-hardened capacitive flexible tactile sensor is obtained.

[0019] Specifically, the sensing unit is attached to the back of the flexible substrate with conductive adhesive to ensure that the array and the coating do not have direct contact; the heavy metal foil film and the sensing unit are composited using a hot press (temperature 200℃, pressure 5MPa, time 10 minutes) to form an inner shielding structure; a rigid lead plate is used as the outer layer and is bonded to the flexible substrate (including the functional coating) by mechanical snap-fit ​​or epoxy resin bonding to finally form a "rigid-flexible" alternating structure.

[0020] The sensor is constructed in two parts: a sensing unit and a protective layer. The sensing unit is the inner layer (located at the bottom), and the protective layer is the outer layer (located at the top). The sensing unit structure, from the outside in (from top to bottom in the diagram), consists of an encapsulation layer, a shielding layer, electrodes, a sensitive layer, electrodes again, and the encapsulation layer (i.e., removing the protective layer reveals the sensing unit). The sensing unit is then treated as a single unit, and insulating protective adhesive is applied to it. A hot press (temperature 200℃, pressure 5MPa, time 10 minutes) is used to bond a heavy metal foil film to the top of the sensor unit, forming a secondary protective layer structure. A rigid lead plate is then applied as the outer layer and bonded with epoxy resin to form the primary protective layer. The final sensor has an alternating "rigid-flexible" structure.

[0021] Preferably, in step S2, the plasma treatment conditions are: plasma treatment for 5 minutes at a power of 100W; and the ultraviolet curing conditions are: ultraviolet curing for 5 minutes at 365 nm.

[0022] Preferably, in step S3, the hot pressing conditions are: temperature 120°C and pressure 5MPa; the plasma treatment conditions are: power 50W and time 3 minutes.

[0023] Preferably, in step S4, the plasma conditions are: power of 800W and Ar gas flow rate of 30 sccm.

[0024] The third aspect of this application also provides the application of the above-mentioned radiation-hardened capacitive flexible tactile sensor in the fields of aerospace, smart wearables, health monitoring, electronic skin and industrial robots.

[0025] Compared with the prior art, this application has the following advantages:

[0026] 1. This application adopts a layered and progressive design, forming a complete technology chain from material innovation to system integration. First, at the basic material layer, a radiation shielding-mechanically flexible integrated material is constructed through a biomimetic gradient radiation-resistant polymer system: a nano-mica / dynamic covalent elastomer composite material is developed based on a nacre brick-mud configuration, utilizing mica sheets to neutralize atomic oxygen and scatter high-energy particles. Second, at the device structure layer, a multi-layer heterogeneous shielding array design is adopted, enhancing the metal-polymer bonding strength through silane coupling agent interface modification, and constructing a three-level gradient shielding system of lead plate-tantalum / tungsten foil-heavy metal foil, combined with magnetron sputtering and low-temperature hot pressing processes to achieve high-precision integration. Finally, at the system level, an innovative tactile-radiation-resistant conformal architecture is proposed: the upper capacitive tactile unit integrates a biomimetic microstructure, the middle layer embeds high-Z materials and radiation-sensitive semiconductors, and the bottom flexible circuit ensures mechanical stability, forming a full-link radiation-resistant solution for the sensing structure.

[0027] 2. This application adopts a composite shielding system that alternates between rigid and flexible elements: the outer layer uses a rigid lead plate as the primary shielding element, which preferentially absorbs and reflects high-energy electrons and gamma rays; the middle functional layer uses tantalum / tungsten foil as a flexible substrate, and a boron-carbon compound or borosilicate-based nano-protective coating is prepared on its surface using vacuum plasma spraying technology, which effectively absorbs neutrons and high-energy protons through nuclear reactions; the inner layer is directly integrated with the sensing unit, and the final shielding against secondary gamma rays and residual incident particles is achieved with the help of heavy metal foil film. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of this application or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the sensor unit structure (inner structure);

[0030] Figure 2 This is a schematic diagram of the protective layer structure (outer layer structure);

[0031] Figure 3 This is a schematic diagram of the radiation-hardened capacitive flexible tactile sensor of this application.

[0032] Explanation of reference numerals in the attached figures:

[0033] 1. First protective layer; 2. First encapsulation layer; 3. First shielding layer; 4. Sensitive layer; 5. Second encapsulation layer; 6. Second protective layer. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0035] Unless otherwise specified, the experimental methods used in the embodiments of this application are all conventional methods.

[0036] In the following examples, unless otherwise specified, all raw materials can be obtained by commercial purchase or conventional methods.

[0037] It should be noted that radiation hardening is a core technology for ensuring the stable operation of spacecraft in extreme space radiation environments. Space radiation (such as cosmic rays and solar flares) can cause electronic devices to degrade or fail. Radiation hardening, through shielding design and material optimization, effectively protects against radiation damage such as total dose effects and single-event effects, ensuring the functional stability of spacecraft during their on-orbit operation.

[0038] The working principle of the capacitive flexible tactile sensor in this application is as follows:

[0039] The working principle of capacitive flexible tactile sensors is based on the physical properties of parallel-plate capacitors, and its core formula is:

[0040]

[0041] Where C is capacitance. Here, A is the dielectric constant, A is the electrode area, and d is the electrode spacing. When an external force is applied to the sensor surface, it causes changes in the electrode spacing, relative area, or dielectric constant, resulting in a change in capacitance. The internal circuitry of the sensor detects this capacitance change in real time and converts it into an electrical signal output, thereby enabling the sensing of physical quantities such as pressure and touch. By optimizing the material system (e.g., using special polymers or composite materials) and innovative structures (e.g., interdigitated or sandwich designs), radiation-induced material performance degradation can be further reduced, ensuring that the sensor maintains stable capacitance change detection capabilities even under irradiation.

[0042] The technical solution consists of two aspects: core sensitive materials and sensing structures. Addressing the common ionizing and non-ionizing radiation in space, it's necessary to consider the structural damage to composite sensitive materials caused by shielding against ionizing radiation, as well as suppressing heat accumulation due to radiative thermal effects. The main approaches include selecting flexible substrates with good radiation resistance, filling the substrate or electrode layers with radiation-resistant materials, and designing flexible encapsulation structures that can shield or absorb radiation.

[0043] Materials: This application addresses the need for radiation-hardened sensors by employing a biomimetic composite material system with a gradient functional distribution. A mica-polyimide gradient, combining rigidity and flexibility, is used as the shielding layer, and a polyarylsulfone / fluorosilicone heterostructure interface protective layer is employed.

[0044] Structure: This application also adopts a combination of rigid and flexible shielding materials, core sensitive materials, and barrier encapsulation materials, introducing a gradient protection design with reflection, absorption, and secondary shielding structures. A gradient radiation protection structure for the sensor is established, preferentially absorbing and reflecting high-energy rays in the outer layer, and then shielding secondary radiation through secondary protection. A layered sandwich structure is designed for the specific environment of medium- and high-orbit radiation to reduce structural damage and signal interference caused by radiation.

[0045] Packaging: Comprehensive improvement in stability and lifespan through cross-scale packaging barrier optimization.

[0046] Example 1

[0047] like Figure 1-3 As shown, the capacitive flexible tactile sensor in this embodiment includes a first protective layer 1, a first encapsulation layer 2, a first shielding layer 3, a sensitive layer 4, a second encapsulation layer 5, and a second protective layer 6 arranged sequentially from bottom to top.

[0048] The first shielding layer 3 is specifically made of the following materials: the surface layer uses high-density nano-mica sheets arranged in parallel and stacked in an alternating manner to form a radiation shielding "brick" structure; the bottom layer uses dynamic covalently cross-linked ETTPBAT elastomer as the "mud" phase matrix, and forms a hydrogen bond-epoxy interpenetrating network with tannic acid phenolic hydroxyl groups and epoxidized soybean oil.

[0049] The material of the sensitive layer 4 is: tellurium nanowire / PEDOT:PSS composite thermoelectric gel and dynamic disulfide bond self-healing network; a three-dimensional ion transport channel is constructed with tellurium nanowires, and a dynamic disulfide bond SS topology network is introduced; the microcavity structure is designed as a biomimetic pyramid array.

[0050] The material of the first encapsulation layer 2 or the second encapsulation layer 5 is specifically: a multi-layer composite structure is constructed based on polysulfone or fluorosilicone gradient heterogeneous protection technology; the outer layer uses polysulfone-doped mica sheets to form a dense cross-linked network, the inner layer uses dynamically cross-linked fluorosilicone and the modulus is adjusted by PDMS-urea bonds; nano-mica constructs a micro-nano secondary superhydrophobic structure, and the interlayer is formed by multiple bonds between the catechol / amine groups of polydopamine coupling agent, polysulfone sulfonic acid groups, and fluorosilicone hydroxyl groups.

[0051] Specifically, the material of the first shielding layer 3 is: the surface layer uses a material with a density of 2.77 g / cm³. 3The nano-mica sheets are arranged in parallel and stacked in an alternating manner to form a structure in which the nano-mica sheets are arranged in parallel and stacked in an alternating manner; the bottom layer uses dynamically covalently cross-linked ETTPBAT elastomer as the matrix, and hydrogen bond-epoxy interpenetrating network is formed with tannic acid phenolic hydroxyl groups and epoxidized soybean oil.

[0052] The sensitive layer 4 material is specifically: tellurium nanowire / PEDOT:PSS composite thermoelectric gel and dynamic disulfide bond self-healing network; an ion conduction path with a highly interconnected three-dimensional network structure is constructed using tellurium nanowires, and the three-dimensional network is formed by the self-assembly of tellurium nanowires, with a large number of nanoscale pores inside the network, and a dynamic disulfide bond SS topology network is introduced; the tellurium nanowire / PEDOT:PSS composite material is prepared into a polyelectrolyte elastomer micro pyramid array structure using soft photolithography, and the pyramid array structure is a uniformly arranged quadrangular pyramid shape microstructure with a height of 10 micrometers, a base width of 10 micrometers, and a height angle of 52°.

[0053] The first encapsulation layer 2 or the second encapsulation layer 5 is specifically made of the following material: based on polysulfone or fluorosilicone gradient heterogeneous protection technology, a multilayer structure is constructed in which the outer layer is made of polysulfone-doped mica sheets to form a dense cross-linked network, and the inner layer is made of dynamically cross-linked fluorosilicone with modulus adjusted by PDMS-urea bonds; the outer layer is made of polysulfone-doped mica sheets to form a dense cross-linked network, and the inner layer is made of dynamically cross-linked fluorosilicone with modulus adjusted by PDMS-urea bonds; nano-mica constructs a micro-nano secondary superhydrophobic structure, and the interlayer is formed by multiple bonds between the catechol / amine groups of polydopamine coupling agent and polysulfone sulfonic acid groups and fluorosilicone silanol groups.

[0054] The method for fabricating the above-mentioned radiation-hardened capacitive flexible tactile sensor includes the following steps:

[0055] S1. Mica sheets are placed in a plasma cleaner and treated for 5 minutes at 300W power and 0.1 mbar pressure to remove surface impurities and enhance activity. They are then dispersed in anhydrous ethanol and ultrasonically treated for 30 minutes at 40kHz to form a uniform suspension. ETTPBAT and epoxidized soybean oil are mixed at a 1:3 mass ratio, with 2% tannic acid added as a crosslinking agent. The mixture is stirred at 80℃ for 2 hours, forming a self-healing elastomer through dynamic bonding between the phenolic hydroxyl groups and epoxy groups of tannic acid. The nano-mica sheet suspension is mixed with the ETTPBAT matrix at a 1:1 mass ratio. The mixture is injected into a porous mold with a pore size of 0.2μm using a vacuum filtration method and filtered under 0.1 MPa pressure to allow the nano-mica sheets to be directionally deposited to form a parallel layer. The second layer of mica sheets is rotated 90° and stacked using a mechanical transfer method, repeated three times to form a composite structure with a thickness of 50μm, thus obtaining a shielding layer.

[0056] S2, TeCl4, and Na2SeO3 solution were reacted in a 1:1 molar ratio, PVP stabilizer was added, and the reaction was carried out at 160℃ for 8 hours. After centrifugation at 5000 rpm for 10 minutes, nanowires with a diameter of 50 nm and a length of 1 μm were collected. PEDOT:PSS solution was mixed with tellurium nanowires at a volume ratio of 1:0.5, 0.1% sodium dodecyl sulfate was added as a dispersant, and 1% dithiothreitol (DTT) was added. A reversible SS bond topological network was formed through a redox reaction, and the reaction was stirred at 60℃ for 1 hour to obtain a composite gel. A pyramid array with a height of 50 μm and a spacing of 100 μm was formed on a silicon substrate by laser direct writing. Plasma treatment (plasma treatment at 100W power for 5 minutes) was used to enhance hydrophilicity. The composite gel was injected into a template and cured by ultraviolet light (ultraviolet light curing at 365nm for 5 minutes) to form a microcavity structure, resulting in sensitive layer 4.

[0057] S3. Polyarylsulfone was dissolved in NMP solvent and mixed with nano-mica sheets at a mass ratio of 9:1. The mixture was ultrasonically dispersed for 1 hour. The solution was coated onto a polytetrafluoroethylene film, dried at 80°C, and then peeled off to form a dense layer with a thickness of 20 μm. Fluorosilicone prepolymer and PDMS-urea bonds were mixed at a mass ratio of 1:0.2, and 0.5% dibutyltin dilaurate was added as a catalyst. The modulus was controlled at 1 MPa by controlling the proportion of PDMS-urea bonds to 10%. Subsequently, a dynamic cross-linked network with a thickness of ≤50 μm was formed by hot pressing (temperature 120°C, pressure 5 MPa). Finally, after coating with polydopamine coupling agent (0.1% mass ratio), a micro-nano superhydrophobic structure was constructed by plasma treatment (power 50W, time 3 minutes) to obtain the encapsulation layer.

[0058] S4. Cut the lead plate to the target size (roughly consistent with the sensor size), and polish the surface to Ra≤0.8μm; remove surface oxides by chemical cleaning, ultrasonically clean with acetone for 10 minutes, and dry for later use; place the tantalum foil in a plasma cleaner, introduce Ar gas (flow rate 50sccm), and treat with 300W power for 5 minutes to remove surface contaminants and activate the surface; deposit a 10nm thick Ti transition layer on the surface using an ion sputtering instrument to enhance the coating adhesion; mix borosilicate-based nanopowder with organic binder polyurethane at a mass ratio of 7:3, and ball mill for 6 hours to form a uniform slurry; load the slurry into a vacuum plasma spraying system, and spray the powder onto the tantalum foil surface through plasma (power 800W, Ar gas flow rate 30sccm) at a spraying distance of 100mm for 10 minutes; after spraying, cure the sample in a vacuum oven at 80℃ for 2 hours to remove organic solvents and obtain a protective layer;

[0059] S5, such as Figure 3As shown, the first protective layer 1, the first encapsulation layer 2, the first shielding layer 3, the sensitive layer 4, the second encapsulation layer 5, and the second protective layer 6 are assembled from bottom to top. Each layer is bonded with epoxy resin. The electrodes are made of Cu metal coated with Au, and the leads are generally copper wires. The electrodes above and below the sensitive layer are led out for signal transmission, resulting in a radiation-hardened capacitive flexible tactile sensor.

[0060] The sensing unit is attached to the back of the flexible substrate with conductive adhesive to ensure that the array and the coating do not have direct contact. The heavy metal foil film is composited with the sensing unit using a hot press (temperature 200℃, pressure 5MPa, time 10 minutes) to form an inner shielding structure. The rigid lead plate is used as the outer layer and is bonded to the flexible substrate (including the functional coating) by mechanical snap-fit ​​or epoxy resin bonding to finally form a "rigid-flexible" alternating structure.

[0061] Example 2

[0062] The capacitive flexible tactile sensor provided in this embodiment can be referred to in Embodiment 1, except that the radiation-hardened capacitive flexible tactile sensor includes a first protective layer 1, a first encapsulation layer 2, a first shielding layer 3, a sensitive layer 4, a second shielding layer, a second encapsulation layer 5, and a second protective layer 6 arranged sequentially from bottom to top.

[0063] It should be noted that the second shielding layer refers to setting up another shielding layer. The prefixes "first" and "second" are only used for convenience of description and will not be elaborated on here.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A radiation-hardened capacitive flexible tactile sensor, characterized in that, It includes, from bottom to top, a first protective layer, a first encapsulation layer, a first shielding layer, a sensitive layer, a second encapsulation layer, and a second protective layer.

2. The radiation-hardened capacitive flexible tactile sensor according to claim 1, characterized in that, The radiation-hardened capacitive flexible tactile sensor comprises, from bottom to top, a first protective layer, a first encapsulation layer, a first shielding layer, a sensitive layer, a second shielding layer, a second encapsulation layer, and a second protective layer.

3. The radiation-hardened capacitive flexible tactile sensor according to claim 2, characterized in that, The material of the first or second shielding layer is specifically: the surface layer uses a material with a density of 2.77 g / cm³. 3 The nano-mica sheets are arranged in parallel and stacked in an alternating manner to form a structure in which the nano-mica sheets are arranged in parallel and stacked in an alternating manner; the bottom layer uses dynamically covalently cross-linked ETTPBAT elastomer as the matrix, and hydrogen bond-epoxy interpenetrating network is formed with tannic acid phenolic hydroxyl groups and epoxidized soybean oil.

4. The radiation-hardened capacitive flexible tactile sensor according to claim 2, characterized in that, The sensitive layer material is specifically: tellurium nanowire / PEDOT:PSS composite thermoelectric gel with dynamic disulfide bond self-healing network; an ion conduction pathway with a highly interconnected three-dimensional network structure is constructed using tellurium nanowires, which form a three-dimensional network through self-assembly, with a large number of nanoscale pores inside the network, and a dynamic disulfide bond SS topology network is introduced; the tellurium nanowire / PEDOT:PSS composite material is prepared into a polyelectrolyte elastomer micro pyramid array structure using soft photolithography, the pyramid array structure is a uniformly arranged quadrangular pyramid shape microstructure with a height of 10 micrometers, a base width of 10 micrometers, and a height angle of 52°.

5. The radiation-hardened capacitive flexible tactile sensor according to claim 2, characterized in that, The first or second encapsulation layer material is specifically: based on polysulfone or fluorosilicone gradient heterogeneous protection technology, a multilayer structure is constructed with an outer layer of polysulfone-doped mica sheets forming a dense cross-linked network, and an inner layer of dynamically cross-linked fluorosilicone with modulus adjusted by PDMS-urea bonds; the outer layer of polysulfone-doped mica sheets forming a dense cross-linked network, and the inner layer of dynamically cross-linked fluorosilicone with modulus adjusted by PDMS-urea bonds; nano-mica constructs a micro-nano secondary superhydrophobic structure, and the interlayer is bonded by the catechol / amine groups of polydopamine coupling agent to polysulfone sulfonic acid groups and fluorosilicone silanol groups.

6. A method for fabricating a radiation-hardened capacitive flexible tactile sensor as described in claim 1, characterized in that, Includes the following steps: S1. The mica sheets are subjected to plasma cleaning to remove surface impurities and enhance activity; It was then dispersed in anhydrous ethanol and ultrasonically treated to form a homogeneous suspension. ETTPBAT is mixed with epoxidized soybean oil, a crosslinking agent is added, and the mixture is stirred to form a self-healing elastomer. A nano-mica sheet suspension is mixed with the ETTPBAT matrix, and the mixture is injected into a porous mold using a vacuum filtration method and then filtered. The second layer of mica sheets is rotated and stacked using a mechanical transfer method to obtain a shielding layer. S2, TeCl4, and Na2SeO3 solutions were mixed, a stabilizer was added, and the mixture was reacted. The nanowires were collected by centrifugation. PEDOT:PSS solution was mixed with tellurium nanowires, a dispersant and dithiothreitol (DTT) were added, and a reversible SS bond topological network was formed through a redox reaction. After stirring, a composite gel was obtained. A pyramid array was formed on a silicon substrate by laser direct writing, and plasma treatment was used to enhance hydrophilicity. The composite gel was injected into a template and cured by ultraviolet light to form a microcavity structure, thus obtaining a sensitive layer. S3. Polyarylsulfone is dissolved in a solvent and mixed with nano-mica sheets, then ultrasonically dispersed. The solution is coated onto a polytetrafluoroethylene film, dried, and then peeled off to form a dense layer. Fluorosilicone prepolymer is mixed with PDMS-urea bonds, and a catalyst is added. Subsequently, a dynamic cross-linked network is formed by hot pressing. Finally, after coating with a polydopamine coupling agent, a micro-nano superhydrophobic structure is constructed by plasma treatment to obtain the encapsulation layer. S4. Cut the lead plate to the target size and polish the surface; remove surface oxides by chemical cleaning, ultrasonic cleaning, and dry for later use; perform plasma cleaning on the tantalum foil to remove surface contaminants and activate the surface; deposit a Ti transition layer on the surface; Borosilicate-based nanopowder was mixed with an organic binder, polyurethane, and ball-milled to form a uniform slurry. The slurry was then loaded into a vacuum plasma spraying system, and the powder was sprayed onto the surface of a tantalum foil using plasma. After spraying, the sample was cured to remove the organic solvent and obtain a protective layer. S5. The first protective layer, the first encapsulation layer, the first shielding layer, the sensitive layer, the second encapsulation layer and the second protective layer, which are arranged from bottom to top, are assembled. Each layer is bonded with epoxy resin. The electrodes are made of Cu metal coated with Au layer, and the leads are generally copper wires. The electrodes above and below the sensitive layer are led out for signal transmission. A radiation-hardened capacitive flexible tactile sensor is obtained.

7. The method for fabricating a radiation-hardened capacitive flexible tactile sensor according to claim 6, characterized in that, In step S2, the plasma treatment conditions are: plasma treatment for 5 minutes at a power of 100W; the ultraviolet curing conditions are: ultraviolet curing for 5 minutes at 365 nm.

8. The method for fabricating a radiation-hardened capacitive flexible tactile sensor according to claim 6, characterized in that, In step S3, the hot pressing conditions are: temperature 120℃, pressure 5MPa; the plasma treatment conditions are: power 50W, time 3 minutes.

9. The method for fabricating a radiation-hardened capacitive flexible tactile sensor according to claim 6, characterized in that, In step S4, the plasma conditions are: power of 800W and Ar gas flow rate of 30sccm.

10. The application of the radiation-hardened capacitive flexible tactile sensor according to any one of claims 1 to 5 in the fields of aerospace, smart wearables, health monitoring, electronic skin and industrial robots.

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