Fabric-based pressure sensor and preparation method thereof

Abstract

The invention provides a fabric-based pressure sensor, which comprises two adjacent resistor elements and a gasket, and is characterized in that the gasket is arranged between the adjacent resistor elements; the interior of the gasket is hollow; the resistance element comprises a fabric conductive layer and a fiber electrode, and the fiber electrode is sewn on one side, away from the gasket, of the fabric conductive layer; the fiber electrodes are made of elastic fibers, and the fiber electrodes of every two adjacent resistor elements are arranged in a crossed mode so that the fiber electrodes of every two adjacent resistor elements can form stress concentration points under the action of external force. The invention also provides a preparation method of the pressure sensor based on the fabric.

Description

Technical Field

[0001] The present invention relates to the field of sensors, and in particular, to a fabric-based pressure sensor and a preparation method thereof. Background Art

[0002] In order to provide richer tactile perception information during human-computer interaction, pressure sensors, as devices that can detect externally applied pressures, play an important role. Pressure sensors can simulate the perception ability of the human skin to external stimuli, identify the magnitude, direction, and distribution of pressures, and greatly promote the research and development in the field of interaction between humans and intelligent devices as well as the perception of the surrounding environment by robots.

[0003] At present, certain progress has been made in the research of pressure sensors, and they can output specific electrical signals according to changes in externally applied pressures. However, there are still some challenges in practical applications. One of them is the deployment in complex environments. Most existing pressure sensors are integrated on rigid substrates and it is difficult to effectively deploy them on complex surfaces such as uneven or curved surfaces. Another challenge is that the manufacturing process of existing pressure sensors usually requires precision manufacturing processes and multiple steps of processing, resulting in high costs and long production cycles, and it is difficult to achieve large-scale preparation.

[0004] In response to the above challenges, researchers have developed fabric-based pressure sensors, which have the advantages of flexibility, breathability, lightness, and can be mass-produced, solving some problems existing in some traditional sensors. However, due to the influence of the mechanical properties of the fabric material itself, although its sensitivity is relatively high, the detection range is relatively narrow. Summary of the Invention

[0005] The technical problem to be solved by the invention is to provide a fabric-based pressure sensor that can expand the pressure detection range of the pressure sensor, has a simple structure, and is easy to prepare.

[0006] To solve the above technical problem, the present invention provides a fabric-based pressure sensor, including two adjacent resistance elements and a gasket, the gasket is arranged between the adjacent resistance elements; the gasket is hollow inside;

[0007] The resistance element includes a fabric conductive layer and a fiber electrode, and the fiber electrode is stitched to the side of the fabric conductive layer facing away from the gasket;

[0008] The fiber electrode uses elastic fibers, and the fiber electrodes of two adjacent resistance elements are arranged in a cross pattern so that the fiber electrodes of two adjacent resistance elements form stress concentration points under external forces.

[0009] In some embodiments, the thickness of the gasket is between 0.2 - 0.6 mm.

[0010] In some embodiments, the side length of the fabric conductive layer is between 10-12 mm; and the length of the fiber electrode is 12-14 mm.

[0011] In some of the embodiments, water-based polyurethane is attached to the surface of the fabric conductive layer.

[0012] In order to solve the above technical problems, the present invention provides a method for preparing the above fabric-based pressure sensor, comprising the following steps:

[0013] Step 1: Use alcohol to pre-treat the surface of the fabric and the elastic fiber, and soak the pre-treated fabric and the elastic fiber in a conductive solution respectively;

[0014] Step 2: drying the fabric dipped in the conductive solution and the elastic fiber obtained in step 1 to form the fabric conductive layer and the fiber electrode;

[0015] Step 3: Suture the fiber electrode obtained in step 2 onto the fabric conductive layer to form a single resistor element;

[0016] Step 4: Repeat steps 1-3 to obtain a plurality of the resistor elements; attach two adjacent resistor elements to the gaskets respectively according to the direction in which the fiber electrodes are cross-arranged to form a face-to-face vertical stacking structure;

[0017] Step 5: Lead out a conductive path from the fiber electrode.

[0018] In some embodiments, the step 1 is specifically:

[0019] S1: Soak a sterile cotton cloth in alcohol and wipe the surface of the fabric and the elastic fiber, and leave the elastic fiber and fabric to dry;

[0020] S2: preparing single-walled carbon nanotubes and aqueous polyurethane at a mass ratio of 1:5-1:3 to obtain a first conductive solution for soaking fabrics; preparing multi-walled carbon nanotubes and aqueous polyurethane at a mass ratio of 1:3 to obtain a second conductive solution for soaking elastic fibers; placing the centrifuge tube containing the first conductive solution and the centrifuge tube containing the second conductive solution in a CNC ultrasonic cleaner for ultrasonic treatment;

[0021] S3: soaking the fabric pretreated by S1 in the first conductive solution for 20-40 minutes; soaking the elastic fiber pretreated by S1 in the second conductive solution for 5-15 minutes.

[0022] In some of these embodiments, step 2 is specifically as follows: Put the fabric impregnated with the conductive solution and the elastic fibers obtained in step 1 into an oven for drying; the drying temperature is 50 - 70 degrees; the drying time of the fabric is 40 - 60 minutes; the drying time of the elastic fibers is 15 - 20 minutes.

[0023] In some of these embodiments, step 3 is specifically as follows:

[0024] S1: Cut the fabric conductive layer obtained in step 2 into square pieces with a side length of 10 - 12 mm 2 and at the same time, cut the length of the fiber electrode longer than the side length of the fabric conductive layer by 12 - 14 mm;

[0025] S2: Suture and cover one fiber electrode on the surface of the fabric conductive layer, and the suture position is the axis of symmetry of the midpoint connection of two opposite sides of the fabric conductive layer, so as to obtain a single said resistance element.

[0026] 9. The preparation method of the fabric-based pressure sensor according to claim 5, wherein step 4 is specifically as follows:

[0027] S1: Cut the polyester fiber fabric into a gasket with an outer side length of 10 - 12 mm and a square opening with a side length of 4 - 7 mm in the center;

[0028] S2: Bond the sides of the two resistance elements obtained by repeating steps 1 - 3 without the sutured fiber electrodes to the gasket obtained in S1 respectively in the direction of the cross arrangement of the fiber electrodes.

[0029] 10. The present invention also provides an application of the above-mentioned fabric-based pressure sensor. The fabric-based pressure sensor is fixed to the gripper of a robotic arm with a camera and is used for grasping underwater objects.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] 1. By designing the cross-set fiber electrodes, the staggered arrangement of the fiber electrodes forms a small but high-strength stress concentration point, enabling this area to gather and bear the externally applied force, thereby fully compressing the fabric conductive layer located between the cross fiber electrodes, increasing the area of the upper and lower fabric conductive layers 104. Combining with the deformation of the fabric's own structure, more conductive path connections are constructed between the fabric conductive layers, triggering a significant resistance change to match the external pressure change range. At the same time, the fiber electrodes made of elastic fibers have a certain elasticity themselves. After being subjected to external pressure, they will also undergo a certain deformation, increasing the contact area with the fabric conductive layer, thereby further expanding the pressure detection range.

[0032] 2. The conductive material of the fabric conductive layer of the present invention includes waterborne polyurethane, which realizes the firm adsorption of the conductive material on the fabric, enables the fabric device to have the characteristic of being washable, and can exhibit stable pressure sensing performance in special environments such as underwater and high humidity. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic structural diagram of the sensor described in the present invention.

[0034] Figure 2 It is a schematic diagram of the resistor element of the sensor described in the present invention

[0035] Figure 3 It is a schematic diagram of the structural changes of the sensor described in the present invention under different pressing forces, no pressure, light pressure, medium pressure, and heavy pressure.

[0036] Figure 4 It is the output signal of the sensor described in the present invention after being pressed by different magnitudes of pressure.

[0037] Figure 5 It is the current output signal of the sensor described in the present invention under more than 5000 cycles of pressing.

[0038] FIG. 6(a) is a comparison of the sensor described in the present invention under different pressure presses underwater and in a normal environment;

[0039] FIG. 6(b) is a comparison of different frequency presses underwater and in a normal environment;

[0040] Figure 7 It is a test of the resistance change of the conductive fabric and fiber electrode described in the present invention during 2 hours of cyclic washing.

[0041] Reference Signs:

[0042] 101: First fiber electrode; 102: Upper fabric conductive layer; 103, gasket; 104, lower fabric conductive layer; 105, second fiber electrode; 106, polyester thread. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. On the contrary, the present invention covers any alternatives, modifications, equivalent methods and solutions made within the spirit and scope of the present invention defined by the claims.

[0044] In the present invention, terms such as "first", "second", "third", etc. are only used to distinguish similar objects, and do not necessarily describe a specific order or sequence, nor can they be construed as indicating or implying relative importance. In the description, the orientation or positional relationship indicated by "upper", "lower", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention, rather than indicating or implying that the device referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation on the protection scope of the present invention. Further, in order to enable the public to better understand the present invention, in the following detailed description of the present invention, some specific details are described in detail. Those skilled in the art can fully understand the present invention without the description of these details.

[0045] In addition, in the description of the present application, unless otherwise specified, "a plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally represents an "or" relationship between the associated objects before and after.

[0046] The present invention will be further described below in conjunction with the drawings and specific embodiments, but it is not intended to limit the present invention. The following are the best embodiments of the present invention:

[0047] See Figure 1 and Figure 2 , this embodiment provides a fabric-based pressure sensor, including adjacent upper and lower resistance elements, and a gasket 103, the gasket 103 is disposed between the upper and lower resistance elements; the gasket 103 is hollow inside;

[0048] The upper resistance element includes an upper fabric conductive layer 102 and a first fiber electrode 101, the lower resistance element includes a lower fabric conductive layer 104 and a second fiber electrode 105, and the first fiber electrode 101 and the second fiber electrode 105 are respectively stitched to the side of the upper fabric conductive layer 102 and the lower fabric conductive layer 104 facing away from the gasket 103 through polyester threads 106;

[0049] The fiber electrodes are made of elastic fibers, and the fiber electrodes of the upper fabric conductive layer 102 and the lower fabric conductive layer 104 are arranged in a cross pattern so that the fiber electrodes of adjacent two resistance elements form stress concentration points under an external force.

[0050] When no external pressure is applied, the upper and lower conductive layers are isolated by the spacer 103, no conductive path is formed, and no signal is generated. During the face-to-face encapsulation process of the fiber electrodes in the upper and lower resistance elements, they do not come into direct contact, but need to be cross-placed spatially. When external stimuli of different magnitudes of pressure are applied, the fabric conductive layers of the upper and lower resistance elements come into contact through the central opening of the spacer 103, forming a conductive path. At this time, the resistance of the electrical contact structure changes, thereby reflecting the change in the magnitude of the pressure.

[0051] Furthermore, the upper fabric conductive layer 102 and the lower fabric conductive layer 104 are square in shape with a side length of 10 mm, and the length of the fiber electrode is 13 mm. The outer side length of the spacer 103 is also 10 mm, and it has a hollow square structure with a square opening with a side length of 5 mm in the center.

[0052] Among them, the side length of the fabric conductive layer can be between 10 - 12 mm; the length of the fiber electrode can be between 12 - 14 mm, the outer side length of the spacer 103 can be between 10 - 12 mm, and the material is polyester fiber. The thickness of the spacer 103 is between 0.2 - 0.6 mm, such as 0.2 mm, 0.4 mm, 0.6 mm; the side length of the square opening can be 4 - 7 mm. This is not limited to this embodiment. The internal square opening size of the spacer 103 and the thickness of the spacer 103 can be adjusted according to the required resistance change range and the required initial pressure response threshold. When the opening size is smaller, the resistance change range of the sensor is smaller; when the thickness of the spacer 103 is thinner, the initial pressure response threshold of the pressure sensor is smaller.

[0053] The fabric conductive layer of this embodiment is made by soaking the fabric in a conductive solution containing waterborne polyurethane and then drying it. Therefore, the fabric conductive layer of this embodiment adheres to waterborne polyurethane. Waterborne polyurethane can achieve the firm adsorption of the conductive material on the fabric, making the fabric device have the characteristic of being washable, and at the same time can exhibit stable pressure sensing performance in special environments such as underwater and high humidity.

[0054] The preparation method of the fabric-based pressure sensor of this embodiment includes the following steps:

[0055] Step 1: Pretreat the surfaces of the fabric and the elastic fiber with alcohol, and immerse the pretreated fabric and elastic fiber in the conductive solution respectively;

[0056] Specifically, the steps are as follows:

[0057] S1: Dip the sterile cotton cloth in alcohol, wipe the surfaces of the fabric and the elastic fiber, and let the elastic fiber and the fabric stand still and wait to dry;

[0058] S2: Prepare the first conductive solution for soaking the fabric by mixing single-walled carbon nanotubes and waterborne polyurethane at a mass ratio of 1:3; prepare the second conductive solution for soaking the elastic fiber by mixing multi-walled carbon nanotubes and waterborne polyurethane at a mass ratio of 1:3; place the centrifuge tubes containing the first conductive solution and the second conductive solution into a numerically controlled ultrasonic cleaner and perform ultrasonic treatment for 30 minutes.

[0059] S3: Immerse the fabric pretreated in S1 into the first conductive solution for 40 minutes; immerse the elastic fiber pretreated in S1 into the second conductive solution for 15 minutes.

[0060] Among them, the mass ratio of single-walled carbon nanotubes to waterborne polyurethane in S2 can be between 1:5 and 1:3, the soaking time of the fabric in S3 can be between 20 and 40 minutes, and the soaking time of the elastic fiber can be between 5 and 15 minutes, not limited to this embodiment.

[0061] Step 2: Dry the fabric and the elastic fiber coated with the conductive solution obtained in Step 1 to form the fabric conductive layer and the fiber electrode.

[0062] The specific steps are as follows: Place the fabric soaked in the first conductive solution and the elastic fiber soaked in the second conductive solution obtained in Step 1 into an oven for drying treatment; the treatment temperature is 65 degrees, where the treatment time of the fabric is 50 minutes and the treatment time of the elastic fiber is 20 minutes. After this treatment, the fabric soaked in the first conductive solution and the elastic fiber soaked in the second conductive solution are obtained, that is, the fabric conductive layer and the fiber electrode.

[0063] Among them, the drying treatment temperature range can be between 50 and 70 degrees; the drying time of the fabric can be between 40 and 60 minutes; the drying time of the elastic fiber can be between 15 and 20 minutes, not limited to this embodiment.

[0064] Step 3: Stitch the fiber electrode obtained in Step 2 onto the fabric conductive layer to form a single resistor element.

[0065] The specific steps are as follows: S1: Cut the fabric conductive layer obtained in Step 2 into a square piece of 10 mm 2 and cut the length of the fiber electrode to 13 mm at the same time.

[0066] S2: Use a knitting machine or manually stitch and cover the fiber electrode on the surface of the fabric conductive layer, and the stitching position is the axis of symmetry of the midpoint connection of two opposite sides of the fabric conductive layer, so as to obtain a single resistor element.

[0067] Among them, the fabric conductive layer can be cut into 10 - 12 mm 2For the square pieces, the length range that the fiber electrode can be cut is 12 - 14 mm. This is not limited to this embodiment, as long as each end of the fiber electrode extends 1 - 2 mm beyond the edge of the fabric conductive layer.

[0068] Step 4: Repeat Steps 1 - 3 to obtain two resistance elements; attach the two resistance elements to the gasket 103 respectively in the direction where the fiber electrodes cross, to form a face - to - face vertical stacking structure.

[0069] The specific steps are as follows:

[0070] S1: Use a laser engraving machine to cut the polyester fiber fabric into a hollow square gasket 103 with an outer side length of 10 mm and a square opening with a side length of 5 mm in the center. The laser tube power is 20 W, and the cutting speed is 20 millimeters per second.

[0071] S2: Attach the conductive layers of the two resistance elements obtained by repeating Steps 1 - 3, which do not have the fiber electrodes sewn, to the gasket 103 obtained in S1 respectively in the direction where the fiber electrodes cross, using waterproof tape to form a stable electrical contact structure.

[0072] Among them, the outer side length of the gasket 103 can be between 10 - 12 mm, and the side length of the square opening can be between 4 - 7 mm. This is not limited to this embodiment.

[0073] Step 5: Lead out 30 AWG OK wire at the first fiber electrode 101 and the second fiber electrode 105 as the conductive path. After extending the electrodes, a fabric - based pressure sensor is formed. The conductive path can also adopt at least one of 36 AWG Teflon high - temperature electronic wire, silicone wire, tinned copper electronic wire, and 280D silver fiber conductive wire. This is not limited to this embodiment.

[0074] In this embodiment, the soaked fabric is a cotton fabric with a woven texture, with a thickness of 1 mm. The diameter of the elastic fiber rope is 0.8 mm, and the material is latex wrapped by polypropylene filament weaving. Water - based polyurethane is used to combine with carbon nanotubes to improve the adhesion efficiency of the conductive solution on the fabric and to improve the washable performance of the fabric with carbon nanotubes attached.

[0075] The working principle of the fabric-based washable pressure sensor in this embodiment is as follows: In the static state, the upper fabric conductive layer 102 and the lower fabric conductive layer 104 do not come into contact due to the presence of the spacer 103, lacking a direct contact path, and the sensor is in a high-resistance state; in the light-pressure state, the weaving textures of the upper fabric conductive layer 102 and the lower fabric conductive layer 104 will first come into contact through the hollow spacer 103 structure. At this time, the contact area is small, and this initial contact starts to generate a conduction path, and the total resistance value of the sensor is relatively large. In the medium-pressure state, the contact area between the upper fabric conductive layer 102 and the lower fabric conductive layer 104 increases until complete contact, and the resistance value of the sensor decreases significantly but has not reached the minimum value. In the high-pressure state, the fabric's own weaving structure deforms under pressure, generating more conductive paths, and the contact resistance value at this time almost reaches the minimum value, and the sensor is in a low-impedance state.

[0076] In a pair of cross-set fiber electrodes, when stimulated by an external pressure, the pressure will be concentratedly transmitted to the intersection to form a stress concentration point. This characteristic can be called the "stress aggregation effect". Specifically, when the fiber electrodes of this structure are under force, uneven local stress distribution will occur inside them, resulting in the pressure being mainly concentrated at the intersection. This is because the staggered arrangement of the fibers forms a small but high-strength node, enabling this area to aggregate and bear the external force applied, thereby fully compressing the fabric conductive layer located between the cross fiber electrodes. Increasing the contact area between the upper and lower fabric conductive layers 104 and combining with the deformation of the fabric's own weaving structure, more conductive path connections are constructed between the fabric conductive layers, triggering a significant resistance change to match the external pressure change range.

[0077] At the same time, due to the certain elasticity of the fiber electrodes themselves, they will also deform to a certain extent after being subjected to an external pressure, increasing the contact area with the fabric conductive layer, thereby further expanding the pressure detection range. The cross-placed conductive fibers can fully compress the fabric conductive layer as the pressure increases, providing a wider pressure detection range.

[0078] In this embodiment, different pressure magnitude pressing tests, more than 5000-cycle pressing tests, underwater different pressure magnitude pressing, different frequency pressing tests, and resistance change tests after washing the conductive fabric and conductive fibers were carried out on the fabric-based washable pressure sensor.

[0079] As Figure 4 shown, the output signal of pressing on the sensor surface using a stepper motor, where the pressure value is provided by a pressure gauge fixed at the front end of the stepper motor. The results show that the pressure sensor can feedback different magnitudes of pressure within a wide range and output response signals with significant distinguishability.

[0080] As Figure 5As shown, a cyclic pressing test of the sensor using a stepper motor was conducted more than 5,000 times. The results show that the fabric-based pressure sensor can still maintain a stable signal output after multiple pressing tests, proving that the device structure can overcome the disadvantage of insufficient durability of the fabric itself and endowing the fabric pressure sensor with excellent durability.

[0081] As shown in Figure 6, the fabric-based pressure sensing was deployed in an underwater environment, and a stepper motor combined with a pressure gauge was used to press the device with different pressure magnitudes and frequencies. The results show that the device can stably respond to pressure changes in the underwater environment ( Figure 6a ), and can respond to presses with a frequency of 0.25 - 2 Hz ( Figure 6b ), proving that the device can still maintain stable sensing performance in the underwater environment.

[0082] As Figure 7 shown, the resistance tests of the fabric conductive layer and the fiber electrodes were carried out after water washing. During the continuous 2-hour water washing process, the resistances of the conductive fabric and the conductive fiber did not change significantly, proving that the adhesion efficiency of the conductive material on the fabric surface is high. This result shows that different from traditional fabric sensors, the conductive fabric and conductive fiber prepared in the present invention have the performance of being washable.

[0083] The fabric-based pressure sensor of this embodiment was fixed on the gripper of a robotic arm with a camera using needles and threads or tape for grasping underwater objects. Since the camera is affected by underwater light refraction and water surface fluctuations, it is impossible to accurately locate the grasping target. At this time, the fabric-based pressure sensor can provide pressure signal feedback for the tactile exploration of the robotic arm underwater. By waving the robotic arm underwater until it touches the target object, the positioning and grasping of the underwater target are realized. When using the robotic arm to grasp items of different sizes, materials, and weights, the fabric pressure sensor can provide real-time pressure feedback during the process of grasping different items, and the robotic arm automatically adjusts the force of the mechanical gripper according to the pressure signal, thereby realizing the adaptive grasping of multiple types of items.

Claims

1. A fabric-based pressure sensor, characterized in that: It comprises two adjacent resistor elements and a gasket, wherein the gasket is arranged between the adjacent resistor elements; the gasket is hollow inside; The resistor element comprises a fabric conductive layer and a fiber electrode, wherein the fiber electrode is sewn to a side of the fabric conductive layer away from the gasket; The fiber electrodes are made of elastic fibers, and the fiber electrodes of two adjacent resistor elements are cross-arranged so that the fiber electrodes of the two adjacent resistor elements form stress concentration points under the action of external force.

2. The fabric-based pressure sensor according to claim 1, characterized in that The thickness of the gasket is between 0.2-0.6 mm.

3. The fabric-based pressure sensor of claim 1, wherein: The side length of the fabric conductive layer is between 10-12 mm; the length of the fiber electrode is 12-14 mm.

4. The fabric-based pressure sensor of claim 1, wherein: Aqueous polyurethane is attached to the surface of the fabric conductive layer.

5. A method for preparing a fabric-based pressure sensor according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: Use alcohol to pre-treat the surface of the fabric and the elastic fiber, and soak the pre-treated fabric and the elastic fiber in a conductive solution respectively; Step 2: drying the fabric dipped in the conductive solution and the elastic fiber obtained in step 1 to form the fabric conductive layer and the fiber electrode; Step 3: Suture the fiber electrode obtained in step 2 onto the fabric conductive layer to form a single resistor element; Step 4: Repeat steps 1-3 to obtain a plurality of the resistor elements; attach two adjacent resistor elements to the gaskets respectively according to the direction in which the fiber electrodes are cross-arranged to form a face-to-face vertical stacking structure; Step 5: Lead out a conductive path from the fiber electrode.

6. The method for preparing a fabric-based pressure sensor according to claim 5, characterized in that: The step 1 is specifically as follows: S1: Soak a sterile cotton cloth in alcohol and wipe the surface of the fabric and the elastic fiber, and leave the elastic fiber and fabric to dry; S2: preparing single-walled carbon nanotubes and aqueous polyurethane in a mass ratio of 1:5-1:3 to obtain a first conductive solution for soaking fabric; The multi-walled carbon nanotubes and waterborne polyurethane are prepared in a mass ratio of 1:3 to obtain a second conductive solution for soaking the elastic fiber; the centrifuge tube containing the first conductive solution and the centrifuge tube containing the second conductive solution are placed in a numerically controlled ultrasonic cleaner for ultrasonic treatment; S3: soaking the fabric pretreated by S1 in a first conductive solution for 20-40 minutes; soaking the elastic fiber pretreated by S1 in a second conductive solution for 5-15 minutes.

7. The method for preparing a fabric-based pressure sensor according to claim 5, characterized in that: The step 2 specifically comprises: putting the fabric soaked with the conductive solution obtained in step 1 and the elastic fiber into an oven for drying; the drying temperature is 50-70 degrees; the drying time of the fabric is 40-60 minutes; and the drying time of the elastic fiber is 15-20 minutes.

8. The method for preparing a fabric-based pressure sensor according to claim 5, characterized in that: The step 3 is specifically as follows: S1: Cut the conductive fabric layer obtained in step 2 into 10-12 mm pieces 2 The fiber electrode is cut to be longer than the side length of the fabric conductive layer, and the length is 12-14 mm; S2: Sewing a fiber electrode to cover the surface of the fabric conductive layer, the sewing position is the symmetry axis of the line connecting the midpoints of two opposite sides of the fabric conductive layer, so as to obtain a single resistor element.

9. The method for preparing a fabric-based pressure sensor according to claim 5, characterized in that: The step 4 is specifically as follows: S1: Cut the polyester fabric into a gasket with an outer side length of 10-12 mm and a square opening with a side length of 4-7 mm in the center; S2: The two resistor elements obtained by repeating steps 1-3 are respectively fitted with the gaskets obtained in S1 on the sides where the fiber electrodes are not stitched, according to the direction in which the fiber electrodes are crossed.

10. An application of a fabric-based pressure sensor according to any one of claims 1 to 4, characterized in that: The fabric-based pressure sensor is fixed to the gripper of a robotic arm with a camera and is used for grasping underwater objects.

Images