A rigid-flexible coupled tactile sensor and a preparation method thereof

Abstract

The application discloses a rigid-flexible coupled tactile sensor and a preparation method thereof, and relates to the technical field of tactile sensing. The tactile sensor is characterized in that a pressure-sensitive sensing layer is arranged in a flexible positioning sleeve, in an initial state, the pressure-sensitive sensing layer and a sensing electrode keep a preset gap, when the tactile sensor is subjected to external pressure, the flexible positioning sleeve is subjected to curvature compression deformation, so that the pressure-sensitive sensing layer moves towards the sensing electrode until the two are in contact and a regular resistance change is generated, and accurate pressure sensing is realized, wherein the pressure-sensitive sensing layer is a porous conductive sponge. The application realizes threshold trigger contact of the pressure-sensitive layer and the electrode by using the pressure curvature deformation of the flexible positioning sleeve, and solves the problems of high static power consumption and significant zero drift of the traditional piezoresistive sensor, and realizes zero power standby and stable measurement starting point.

Description

Technical Field

[0001] This invention relates to the field of tactile sensing technology, and more specifically, to a rigid-flexible coupled tactile sensor and its fabrication method. Background Technology

[0002] Tactile sensing technology, as a core support for human-computer interaction, intelligent robotics, and other fields, places stringent requirements on the sensitivity, power consumption control, and environmental adaptability of sensors. Piezoresistive tactile sensors perceive pressure based on the change in resistivity of materials under stress. They can sense extremely small pressure signals and have a wide dynamic measurement range, making them widely studied in precision tactile detection scenarios.

[0003] However, the performance of existing piezoresistive tactile sensors is limited by inherent defects in the initial contact design. In the initial state, the continuous contact of the conductive structure results in a constant current flow through the circuit, generating static power consumption and causing zero-point drift due to the microscopic randomness of the contact state between the microstructure and the electrodes, leading to instability in the measurement starting point. Simultaneously, in the low-pressure range, the material resistivity changes gradually, resulting in insufficient sensitivity in this range, making it difficult to meet the requirements of high-precision tactile sensing. These problems severely restrict the practical application of piezoresistive tactile sensors in low-power, high-precision scenarios, necessitating breakthroughs in structural innovation and fabrication process optimization to overcome these technical bottlenecks. Summary of the Invention

[0004] To address the aforementioned technical deficiencies, this invention provides a rigid-flexible coupled tactile sensor and its fabrication method. It aims to solve the technical problems of high static power consumption, significant zero-point drift, and insufficient sensitivity in the low-pressure range of existing piezoresistive tactile sensors. Through an innovative initial disconnect rigid-flexible coupling structure design, it achieves a comprehensive performance improvement in sensor performance, including zero-power standby, stable measurement start point, and high sensitivity response.

[0005] The specific plan is as follows: The first aspect of this invention provides a rigid-flexible coupled tactile sensor, comprising, from top to bottom: The base cover is rigid enough to provide overall support; A rigid base, located inside the base cover, has protrusions distributed on its surface; A pressure-sensitive sensing layer is fixed to the end face of the protrusion; The flexible positioning sleeve engages with the outer periphery of the boss and the pressure-sensitive sensing layer to achieve the positioning and limiting of the boss, and generates curvature compression deformation when subjected to external pressure, and returns to the original configuration after the pressure is removed. The sensing electrode has its electrode side in contact with the flexible positioning sleeve. In the initial state, the pressure-sensitive sensing layer and the sensing electrode maintain a preset gap. When subjected to external pressure, the pressure-sensitive sensing layer and the sensing electrode come into contact and conduct, generating a change in resistance to realize pressure sensing. The encapsulated housing, which is flexible to accommodate external pressure transmission, covers the periphery of the base cover. The two together form a sealed cavity to integrate all other structures inside the sealed cavity.

[0006] Preferably, the pressure-sensitive sensing layer is a porous conductive sponge, and the number of conductive paths formed by the conductive sponge and the sensing electrode increases or decreases accordingly as the external pressure increases or decreases.

[0007] Preferably, the flexible positioning sleeve is made of silicone.

[0008] Preferably, the base cover and the encapsulation shell are made of PDMS material, and the two achieve differentiated hardness by adjusting the ratio of PDMS precursor and curing agent.

[0009] Preferably, the base cover is formed by curing PDMS precursor and curing agent at a mass ratio of 7.5:1, and the encapsulation shell is formed by curing PDMS precursor and curing agent at a mass ratio of 12:1.

[0010] Preferably, the flexible positioning sleeve is composed of a hollow cylindrical support part and a mushroom-shaped flange, and the mushroom-shaped flange is in contact with the sensing electrode and is a force-bearing surface that is deformed under pressure.

[0011] Preferably, the boss of the rigid base is composed of a first-stage frustum, a second-stage frustum and a third-stage frustum from bottom to top. The second-stage frustum is engaged with the inner wall of the flexible positioning sleeve. The diameter of the first-stage frustum is larger than the diameter of the second-stage frustum, forming a stepped shape. The pressure-sensitive sensing layer is fixed on the end face of the third-stage frustum. The pressure-sensitive sensing layer and the third-stage frustum do not contact the inner wall of the flexible positioning sleeve.

[0012] Preferably, the sensing electrode is composed of a flexible thin film substrate and an electrode unit. When subjected to external pressure, the pressure-sensitive sensing layer comes into contact with the electrode unit, resulting in a change in resistance.

[0013] Preferably, the surface of the rigid base has four protrusions evenly distributed in a circumferential array, and the sensing electrode has four electrode units corresponding to the four protrusions, with each electrode unit outputting a signal independently.

[0014] A second aspect of the present invention provides a method for fabricating a rigid-flexible coupled tactile sensor, used to fabricate the rigid-flexible coupled tactile sensor described in the first aspect of the present invention, comprising the following steps: S1, Preparation of rigid base: Using ABS or PC as raw materials, a rigid base is integrally formed by 3D printing; S2, Prepare flexible positioning sleeve: Use silicone as raw material to mold a flexible positioning sleeve, and fit it onto the outer periphery of the rigid base to complete the positioning assembly; S3, Preparation of pressure-sensitive sensing layer: Cut the porous sponge to a size that matches the end face of the rigid base, immerse it in a conductive particle solution, repeat the immersion and drying operation 3 to 5 times to form a pressure-sensitive sensing layer, and fix the obtained pressure-sensitive sensing layer to the end face of the rigid base with conductive adhesive. S4, Fabrication of sensing electrodes: Using PET or PI as a flexible thin film substrate, the electrodes are sequentially cleaned, treated with oxygen plasma, and then electrode units are fabricated to form sensing electrodes. S5, Prepare the base cover and the encapsulation shell: Prepare mixtures of PDMS precursor and curing agent respectively, wherein the mixture used to form the base cover is mixed at a mass ratio of PDMS precursor to curing agent of 7.5:1, and the mixture used to form the encapsulation shell is mixed at a mass ratio of PDMS precursor to curing agent of 12:1; after stirring evenly, vacuum degassing is performed, and the mixture is poured into the base cover mold and the encapsulation shell mold respectively, and cured at 60℃~80℃ for 2h~4h. After cooling and demolding, the base cover (1) and the encapsulation shell (6) are obtained respectively, wherein the encapsulation shell (6) is reserved with wire lead-out holes; S6, Fabrication of a tactile sensor: The non-electrode side of the sensing electrode is fixed inside the encapsulation shell. The electrode units of the sensing electrode are led outward through the lead-out holes of the conductive wires. The rigid base equipped with the flexible positioning sleeve and the pressure-sensitive sensing layer is then placed into the base cover. Finally, the encapsulation shell is fitted to cover the base cover and the internal structure, and the sealant is used to seal and form a closed cavity, thus obtaining the tactile sensor.

[0015] The present invention has the following beneficial effects: This invention provides a rigid-flexible coupled tactile sensor. Through an innovatively designed initial non-contact rigid-flexible coupling structure, the sensing electrode and the pressure-sensitive sensing layer do not contact each other in the initial state. The threshold-triggered contact between the pressure-sensitive sensing layer and the sensing electrode is achieved by utilizing the pressure-induced curvature deformation of the flexible positioning sleeve. This fundamentally solves the problems of high static power consumption and significant zero-point drift of traditional piezoresistive sensors, achieving zero-power standby and a stable measurement starting point. The pressure-sensitive sensing layer uses a porous conductive sponge with attached conductive particles. Based on the resistance change mechanism of close contact after pressure, it effectively improves the sensing sensitivity of the sensor. The sensor has four independently outputting electrode units arranged circumferentially to form a four-channel sensing architecture, which can realize precise pressure positioning and multi-dimensional information fusion sensing, expanding its application adaptability in human-computer interaction, intelligent robots and other scenarios. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the rigid-flexible coupled tactile sensor of the present invention.

[0017] Figure 2 This is a three-dimensional structural diagram of the rigid base of the tactile sensor with rigid-flexible coupling according to the present invention.

[0018] Figure 3 This is a three-dimensional structural diagram of the flexible positioning sleeve of the rigid-flexible coupling tactile sensor of the present invention.

[0019] Figure 4 This is a schematic diagram of the internal structure of the flexible positioning sleeve of the tactile sensor of the present invention, which features rigid-flexible coupling.

[0020] Figure 5 This is a schematic diagram showing the structural relationship between the flexible positioning sleeve, rigid base, and pressure-sensitive sensing layer of the tactile sensor of the present invention, which features rigid-flexible coupling.

[0021] Figure 6 This is a schematic diagram of the sensing electrode of the rigid-flexible coupled tactile sensor of the present invention.

[0022] The reference numerals in the accompanying drawings of this invention are as follows: 1. Base cover; 2. Rigid base; 21. First-stage frustum; 22. Second-stage frustum; 23. Third-stage frustum; 3. Pressure-sensitive sensing layer; 4. Flexible positioning sleeve; 41. First-stage inner hole; 42. Second-stage inner hole; 5. Sensing electrode; 51. Flexible thin film substrate; 52. Electrode unit; 6. Encapsulation shell. Detailed Implementation

[0023] The technical solutions of the present invention will now be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention.

[0024] Example 1: Please see Figure 1 This embodiment provides a rigid-flexible coupled tactile sensor, including a base cover 1, a rigid base 2, a pressure-sensitive sensing layer 3, a flexible positioning sleeve 4, a sensing electrode 5, and an encapsulation shell 6.

[0025] The base cover 1 has rigidity and is used to provide overall support for the entire tactile sensor.

[0026] Please see Figure 2 The rigid base 2 includes a disc base with four protrusions evenly spaced along the same circumference on its surface. The disc base and all protrusions are made of acrylonitrile-butadiene-styrene copolymer (ABS) or polycarbonate (PC) and are integrally formed by 3D printing. Each protrusion consists of a first-stage frustum 21, a second-stage frustum 22, and a third-stage frustum 23 from bottom to top. The first-stage frustum 21 is fixed to the surface of the disc base, and its diameter is larger than that of the second-stage frustum 22, forming a stepped structure that facilitates positioning and axial limiting during the subsequent assembly of the rigid base 2 and the flexible positioning sleeve 4. The diameter of the third-stage frustum 23 is slightly larger than that of the second-stage frustum 22.

[0027] Please see Figure 1 and Figure 5 The pressure-sensitive sensing layer 3 is a porous conductive sponge with MXene attached. The conductive sponge is circular, with the same diameter as the truncated cone 23, and is fixed to the end face of the truncated cone 23. Each convex cone has a pressure-sensitive sensing layer 3, for a total of four pressure-sensitive sensing layers 3. The conductive sponge is made of melamine sponge or polyurethane sponge. MXene is attached to the sponge skeleton by impregnation. The preferred concentration of the MXene solution is 5 mg / mL to 10 mg / mL, which has high conductivity and high elasticity.

[0028] Please see Figure 3 and Figure 4 The flexible positioning sleeve 4 engages with the outer periphery of the boss and pressure-sensitive sensing layer 3. It consists of a cylindrical support and a mushroom-shaped flange, with the mushroom-shaped flange serving as the force-bearing surface for compression deformation. The flexible positioning sleeve 4 is composed of a primary inner hole 41 and a secondary inner hole 42, arranged from bottom to top. The inner diameter of the primary inner hole 41 is smaller than that of the secondary inner hole 42. When the flexible positioning sleeve 4 engages with the outer periphery of the boss, the secondary frustum 22 of the boss is interference-fitted with the primary inner hole 41 of the flexible positioning sleeve 4, and the primary frustum 21 of the boss is in contact with the end face of the cylindrical support, thereby achieving precise engagement and positioning, as well as axial limiting, during the assembly of the rigid base 2 and the flexible positioning sleeve 4. The flexible positioning sleeve 4 is made of medical-grade silicone, possessing both excellent elastic recovery and structural stability. It adapts to the mechanical requirements of compressive curvature deformation, undergoing curvature compression deformation under external pressure and returning to its original configuration after the pressure is removed.

[0029] Please see Figure 6 The sensing electrode 5 consists of a circular flexible thin film substrate 51 and four electrode units 52 distributed on the flexible thin film substrate 51. The four electrode units 52 are equidistantly arrayed along the circumferential direction on the surface of the flexible thin film substrate 51. Each electrode unit 52 independently leads out signal lines, forming a sensing structure with four independent output signals, realizing accurate acquisition and differentiation of pressure signals. The four electrode units 52 correspond one-to-one with the four pressure-sensitive sensing layers 3. Each electrode unit 52 is coaxial with each pressure-sensitive sensing layer 3. In the initial state, the pressure-sensitive sensing layer 3 and the sensing electrode 5 maintain a preset gap. When subjected to external pressure, the pressure-sensitive sensing layer 3 comes into contact with the electrode unit 52, generating a change in resistance, thus realizing pressure sensing.

[0030] In this embodiment, the flexible thin film substrate 51 is polyethylene terephthalate (PET), and the electrode unit 52 is a gold (Au) electrode prepared by masking and magnetron sputtering.

[0031] The encapsulation housing 6 is flexible to adapt to external pressure transmission. It covers the periphery of the base cover 1, and the two together form a sealed cavity to integrate all other structures inside the sealed cavity. The surface of the sensing electrode 5 without the electrode unit 52 is fixed to the inner wall of the encapsulation housing 6.

[0032] Both the base cover 1 and the encapsulation shell 6 are made of polydimethylsiloxane (PDMS). The different hardnesses of the two are achieved by adjusting the ratio of PDMS precursor to curing agent. Specifically, the base cover 1 is cured by curing PDMS precursor and curing agent at a mass ratio of 7.5:1, which has high structural rigidity to provide stable support; the encapsulation shell 6 is cured by curing PDMS precursor and curing agent at a mass ratio of 12:1, which has relative flexibility to adapt to external pressure transmission and structural encapsulation protection.

[0033] In its initial state, the pressure-sensitive sensing layer 3 is located within the secondary inner hole 42 of the flexible positioning sleeve 4, maintaining a preset gap with the electrode unit 52. When the tactile sensor is subjected to external pressure, the flexible positioning sleeve 4 undergoes controllable curvature compression deformation along the protrusion area, causing the pressure-sensitive sensing layer 3 to shift relative to the sensing electrode 5 until the two make contact and conduct, generating a regular resistance change. Pressure signal is sensed based on the changing resistance. As the pressure increases, the porous conductive sponge of the pressure-sensitive sensing layer 3 is further compressed, the number of internal conductive paths continues to increase, and the resistance decreases, thereby achieving accurate and continuous sensing of different pressure levels and effectively improving the sensing sensitivity of the tactile sensor.

[0034] The fabrication method of the above-mentioned rigid-flexible coupled tactile sensor includes the following steps: S1, Preparation of rigid base 2: Using acrylonitrile-butadiene-styrene copolymer (ABS) or polycarbonate (PC) as raw materials, a rigid base 2 with stepped bosses is integrally formed by 3D printing.

[0035] S2, Prepare the flexible positioning sleeve 4: Use silicone as raw material to mold the flexible positioning sleeve 4, and fit it onto the outer periphery of the rigid base 2, so that the secondary frustum 22 of the rigid base 2 is located inside the primary inner hole 41 of the flexible positioning sleeve 4, and the primary frustum 21 of the rigid base 2 is in contact with the end face of the cylindrical support part of the flexible positioning sleeve 4, thus completing the positioning assembly.

[0036] S3, Preparation of pressure-sensitive sensing layer 3: Cut the porous sponge to a size that matches the end face of the third frustum 23 of the rigid base 2, and then immerse it in an MXene solution with a concentration of 5mg / mL~10mg / mL. Repeat the immersion and drying operation 3~5 times to form pressure-sensitive sensing layer 3. Fix the obtained pressure-sensitive sensing layer 3 to the end face of the third frustum 23 of the rigid base 2 with conductive adhesive.

[0037] S4, Fabrication of sensing electrode 5: Using polyethylene terephthalate (PET) as a flexible thin film substrate 51, it is sequentially cleaned and treated with oxygen plasma. The process parameters for oxygen plasma treatment are: power 100W~200W, treatment time 1min~5min. Subsequently, four independent gold (Au) electrode units 52 are fabricated by masking and magnetron sputtering. The process parameters for magnetron sputtering are: sputtering power 50W~100W, sputtering time 2min~3min, forming a four-channel sensing electrode 5.

[0038] S5, Preparation of base cover 1 and encapsulation shell 6: Prepare mixtures of polydimethylsiloxane (PDMS) precursor and curing agent respectively. The mixture used to form base cover 1 is mixed at a mass ratio of PDMS precursor to curing agent of 7.5:1, and the mixture used to form encapsulation shell 6 is mixed at a mass ratio of PDMS precursor to curing agent of 12:1. After stirring the two mixtures evenly, degas them in a vacuum chamber for 20 min to 30 min. Then, pour the degassed mixtures into the 3D printed base cover mold and encapsulation shell mold respectively, and place them in an oven to cure for 2 h to 4 h at a curing temperature of 60℃ to 80℃. After cooling and demolding, base cover 1 and encapsulation shell 6 are obtained respectively. The encapsulation shell 6 has reserved wire lead-out holes.

[0039] S6, Fabrication of the tactile sensor: The non-electrode side of the sensing electrode 5 is fixed to the inner layer of the encapsulation shell 6. The four independent electrode units 52 are led outward through the wire lead-out holes via conductive wires. The rigid base 2, equipped with the flexible positioning sleeve 4 and the pressure-sensitive sensing layer 3, is then placed into the base cover 1. Finally, the encapsulation shell 6 is fitted to cover the base cover 1 and the internal structure. The sealant is used to seal and form a sealed protective cavity, thus obtaining the rigid-flexible coupled tactile sensor.

[0040] In summary, Example 1 provides a rigid-flexible coupled tactile sensor and its fabrication method. Through rigid-flexible collaborative structural design and multi-material adaptation, it achieves zero-power standby and high-sensitivity sensing. Furthermore, the four-channel design supports pressure positioning and accurate acquisition of multi-dimensional information, making it suitable for multiple scenarios such as human-computer interaction and intelligent robots.

[0041] Example 2: The difference between this embodiment and Embodiment 1 lies in the preparation of the pressure-sensitive sensing layer 3 in step S3. In this embodiment, the conductive particles used in the pressure-sensitive sensing layer 3 are any one of carbon black, carbon nanotubes (CNTs), and graphene, or any combination of two or three of the above, replacing Mxene in Embodiment 1. The remaining steps are the same as in Embodiment 1.

[0042] Example 3: The difference between this embodiment and Embodiment 1 lies in the preparation of the sensing electrode 5 in step S4. In this embodiment, the sensing electrode 5 uses polyimide (PI) as a flexible thin film substrate 51, and the electrode material is selected from any one or more combinations of silver (Ag), platinum (Pt), titanium (Ti), copper (Cu), and indium tin oxide (ITO), replacing Au in Embodiment 1. The remaining steps are the same as in Embodiment 1.

[0043] It should be understood that the specific embodiments described above are only used to illustrate the technical solutions of the present invention and do not constitute a limitation on the scope of protection. Other technical solutions that can be obtained by those skilled in the art through conventional modifications, substitutions or combinations based on the technical concepts disclosed in the present invention should all be considered as not departing from the essence of the present invention, and should accordingly fall within the scope of protection of the present invention.

Claims

1. A rigid-flexible coupled tactile sensor, characterized in that, From top to bottom, they include: The base cover (1) has rigidity to provide overall support; A rigid base (2) is located inside the base cover (1) and has protrusions distributed on its surface; Pressure-sensitive sensing layer (3) is fixed to the end face of the boss; The flexible positioning sleeve (4) engages with the outer periphery of the boss and the pressure-sensitive sensing layer (3) to achieve the positioning and limiting of the boss, and generates curvature compression deformation when subjected to external pressure, and returns to the original configuration after the pressure is removed. The sensing electrode (5) is in contact with the flexible positioning sleeve (4) on its electrode side. In the initial state, the pressure-sensitive sensing layer (3) and the sensing electrode (5) maintain a preset gap. When subjected to external pressure, the pressure-sensitive sensing layer (3) and the sensing electrode (5) come into contact and conduct, generating a change in resistance to realize pressure sensing. The encapsulation shell (6) is flexible to accommodate external pressure transmission and covers the periphery of the base cover (1). The two together form a sealed cavity to integrate all other structures inside the sealed cavity.

2. The rigid-flexible coupled tactile sensor according to claim 1, characterized in that, The pressure-sensitive sensing layer (3) is a porous conductive sponge. As the external pressure it bears increases or decreases, the number of conductive paths formed by the conductive sponge and the sensing electrode (5) increases or decreases accordingly.

3. The rigid-flexible coupled tactile sensor according to claim 1, characterized in that, The flexible positioning sleeve (4) is made of silicone.

4. The rigid-flexible coupled tactile sensor according to claim 1, characterized in that, The base cover (1) and the encapsulation shell (6) are made of PDMS material, and the two achieve different hardness by adjusting the ratio of PDMS precursor and curing agent.

5. The rigid-flexible coupled tactile sensor according to claim 4, characterized in that, The base cover (1) is formed by curing PDMS precursor and curing agent at a mass ratio of 7.5:1, and the encapsulation shell (6) is formed by curing PDMS precursor and curing agent at a mass ratio of 12:

1.

6. The rigid-flexible coupled tactile sensor according to claim 1, characterized in that, The flexible positioning sleeve (4) consists of a hollow cylindrical support part and a mushroom-shaped flange. The mushroom-shaped flange is in contact with the sensing electrode (5) and is a force-bearing surface that is deformed under pressure.

7. The rigid-flexible coupled tactile sensor according to claim 6, characterized in that, The boss of the rigid base (2) is composed of a first-stage frustum (21), a second-stage frustum (22) and a third-stage frustum (23) from bottom to top. The second-stage frustum (22) is engaged with the inner wall of the flexible positioning sleeve (4). The diameter of the first-stage frustum (21) is larger than the diameter of the second-stage frustum (22), forming a stepped shape. The pressure-sensitive sensing layer (3) is fixed on the end face of the third-stage frustum (23). The pressure-sensitive sensing layer (3) and the third-stage frustum (23) do not contact the inner wall of the flexible positioning sleeve (4).

8. The rigid-flexible coupled tactile sensor according to claim 1, characterized in that, The sensing electrode (5) is composed of a flexible thin film substrate (51) and an electrode unit (52). When subjected to external pressure, the pressure-sensitive sensing layer (3) comes into contact with the electrode unit (52), resulting in a change in resistance.

9. The rigid-flexible coupled tactile sensor according to claim 8, characterized in that, The surface of the rigid base (2) is equidistantly arranged with four protrusions along the circumferential direction. The sensing electrode (5) is provided with four electrode units (52) corresponding to the four protrusions, and each electrode unit (52) outputs a signal independently.

10. A method for fabricating a rigid-flexible coupled tactile sensor, characterized in that, The method for preparing the rigid-flexible coupled tactile sensor according to any one of claims 1 to 9 comprises the following steps: S1, Preparation of rigid base (2): Using ABS or PC as raw material, rigid base (2) is integrally formed by 3D printing. S2, Prepare flexible positioning sleeve (4): Use silicone as raw material to mold flexible positioning sleeve (4), and fit it onto the outer periphery of rigid base (2) to complete positioning assembly; S3, Prepare pressure-sensitive sensing layer (3): Cut the porous sponge to a size that matches the end face of the rigid base (2), immerse it in a conductive particle solution, repeat the immersion and drying operation 3 to 5 times to form pressure-sensitive sensing layer (3), and fix the obtained pressure-sensitive sensing layer (3) to the end face of the rigid base (2) with conductive adhesive. S4, Prepare sensing electrode (5): Use PET or PI as flexible thin film substrate (51), clean and treat with oxygen plasma in sequence, and then prepare electrode unit (52) to form sensing electrode (5). S5, Prepare the base cover (1) and the encapsulation shell (6): Prepare mixtures of PDMS precursor and curing agent respectively, wherein the mixture used to form the base cover (1) is mixed at a mass ratio of PDMS precursor to curing agent of 7.5:1, and the mixture used to form the encapsulation shell (6) is mixed at a mass ratio of PDMS precursor to curing agent of 12:1; after stirring evenly, vacuum degassing is performed, and the mixture is poured into the base cover mold and the encapsulation shell mold respectively, and cured at 60℃~80℃ for 2h~4h. After cooling and demolding, the base cover (1) and the encapsulation shell (6) are obtained respectively, wherein the encapsulation shell (6) is reserved with wire lead-out holes; S6, Prepare a tactile sensor: Fix the non-electrode side of the sensing electrode (5) to the inside of the encapsulation shell (6). The electrode units (52) of the sensing electrode (5) are led out through the wire lead-out holes via conductive wires. Then, the rigid base (2) equipped with the flexible positioning sleeve (4) and the pressure-sensitive sensing layer (3) is placed into the base cover (1). Finally, the encapsulation shell (6) is fitted to cover the base cover (1) and the internal structure. The sealant is used to seal and form a closed cavity, thus obtaining the tactile sensor.

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