Flexible stress sensor prepared based on centrifugal spinning fibers

Abstract

A flexible stress sensor prepared based on centrifugal spinning fibers comprises a stress layer and a base layer, and the stress layer is bonded on the base layer; the stress layer comprises a plurality of transverse conductive fibers and two longitudinal conductive fibers, the two longitudinal conductive fibers are connected with the left sides and the right sides of all the transverse conductive fibers respectively, and all the transverse conductive fibers are evenly distributed to form a grating net-shaped structure. And all the transverse conductive fibers and the longitudinal conductive fibers are made of at least one conductive wire. The stress layer is high in mechanical strength and good in stability.

Description

Technical Field

[0001] The present invention relates to an improvement in a flexible stress sensor preparation technology, belongs to the field of wearable devices, and in particular to a flexible stress sensor prepared based on centrifugal spinning fibers. Background Art

[0002] Flexible pressure sensor is a sensor that can measure and detect the pressure applied by an object or medium. It has the characteristics of flexibility and deformability. Unlike traditional rigid pressure sensors, flexible pressure sensors can bend, stretch and twist to adapt to stress changes of different shapes and surfaces. Flexible pressure sensors are usually composed of flexible materials, capacitive sensors, conductive materials or pressure-sensitive materials. Flexible stress sensors have shown broad application prospects in the fields of human-computer interaction, health monitoring and smart wearable devices due to their excellent flexibility, wearability and ability to adapt to complex shapes. Existing flexible sensors generally include a base layer and a stress layer, and the existing stress layer is coated or printed with a conductive melt, and the conductive melt includes a conductive solute and a solvent. Among them, the most widely used conductive solutes are metal wires, carbon fibers, carbon nanotubes, etc. The existing design of the stress layer is a layered material, which leads to low mechanical strength of the stress layer, easy cracks or delamination in application, and poor stability.

[0003] The Chinese patent application with application number CN201811104807.4 and application date September 21, 2018 discloses a wearable flexible stress sensor and its preparation method and application. First, a functional ink suitable for screen printing is prepared, and the ink is printed on a wearable substrate by screen printing to obtain a stress sensor of the required specifications. It is used to monitor physical deformations from small to large ranges such as stretching, bending, touch, etc., and has many applications in the fields of electronic skin such as human joints, expressions, pulse, heartbeat, biomedical applications, human-computer interaction, virtual reality and entertainment technology. The flexible stress sensor has excellent tensile elasticity, excellent linear relationship of the working curve, and good tensile repeatability, but the above scheme does not solve the problem of low mechanical strength and poor stability of the existing stress layer.

[0004] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of this patent application, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to ordinary technicians in this field. Summary of the invention

[0005] The purpose of the present invention is to overcome the problems of low mechanical strength and poor stability of the stress layer in the prior art, and to provide a flexible stress sensor based on centrifugal spinning fibers with high mechanical strength and good stability of the stress layer.

[0006] To achieve the above objectives, the technical solution of the present invention is: a flexible stress sensor prepared based on centrifugal spinning fibers, the flexible stress sensor prepared based on centrifugal spinning fibers comprises a stress layer and a base layer, the stress layer is bonded to the base layer; The stress layer includes a plurality of transverse conductive fibers and two longitudinal conductive fibers, the two longitudinal conductive fibers are respectively connected to the left and right sides of all the transverse conductive fibers, and all the transverse conductive fibers are evenly distributed to form a grid-like structure; All of the transverse conductive fibers and the longitudinal conductive fibers are made of at least one conductive thread.

[0007] The conductive yarn is made by centrifugal spinning. The melt in the centrifugal spinning includes a conductive solute and a conventional polymer. The conventional polymer is any one of PLA, PVA, PVP, and PTF, or a mixture of multiple thereof.

[0008] The centrifugal spinning is operated by the following equipment, including a spinning device, a feed pipe, a heat preservation plate, a heat preservation inner cylinder and a driving outer cylinder; A collecting device is provided on the outer side of the spinning device; The spinning device comprises an arc-shaped plate with an arc-shaped top and a circular plate with a flat bottom, the bottom of the arc-shaped plate is connected to the top of the circular plate, and a discharge port is respectively arranged at the left and right ends of the arc-shaped plate; A material holding cavity is formed between the arc plate and the circular plate, and the spacing of the material holding cavity decreases from the center of the arc plate to the surroundings; The top of the driving outer cylinder is connected to the bottom of the connecting ring, the connecting ring is arranged in the circular plate, the side of the feed pipe is embedded in the top center of the arc plate, a plurality of feed holes are opened at the bottom of the feed pipe, and the spinneret moves centrifugally with the driving outer cylinder; A driving gear is sleeved on the outer side of the driving outer cylinder, and the driving gear is connected to the external driving mechanism; An insulation inner cylinder is arranged inside the driving outer cylinder, the top of the insulation inner cylinder is connected to the bottom of the insulation board, a partition is installed at the center of the bottom of the insulation board, a plurality of air inlet holes are opened at the bottom of the insulation board on the left side of the partition, and a plurality of air exhaust holes are opened at the bottom of the insulation board on the right side of the partition, and hot air circulates through the air inlet holes, the cavity of the insulation board, and the air exhaust holes in sequence; There is a gap between the feed pipe and the insulation plate; The molten material in the material holding cavity flows into the spinneret through the feed hole and is thrown out from the discharge port under the action of centrifugal force.

[0009] Two first annular plates are arranged on the side of the feed pipe, and a fixing ring is arranged on the top of the arc-shaped plate, and the fixing ring is embedded in the gap between the two first annular plates; The feed pipe does not perform centrifugal motion along with the driving outer cylinder.

[0010] The diameter of the connecting ring is the same as the diameter of the driving outer cylinder, and the upper end of the connecting ring is located in the cavity of the spinning device; The inner wall of the connecting ring is connected to the outer side of the heat-insulating inner cylinder.

[0011] Two second annular plates are arranged on the outer side of the connecting ring, and the circular plate is clamped between the two second annular plates; The distance between the second annular plate above and the insulation plate is greater than the distance between the connecting ring and the insulation plate.

[0012] A plurality of ventilation holes are sequentially opened on the side surface of the partition from top to bottom, and the distance between two adjacent ventilation holes is the same.

[0013] The partition is arranged at the center of the insulation board, and all the air inlet holes and air exhaust holes are distributed in a ring shape with the partition as the center; All air inlet holes and air exhaust holes are symmetrically arranged.

[0014] The insulation plate is a circular plate, and the centers of the insulation plate and the feed pipe are located on the same longitudinal axis; The diameter of the insulation board is greater than the diameter of the feed pipe.

[0015] The top of the heat-insulating inner cylinder passes through the connecting ring and is connected to the bottom of the heat-insulating plate, and there is no contact between the heat-insulating plate and the connecting ring.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. In a flexible stress sensor prepared based on centrifugal spinning fibers of the present invention, the flexible stress sensor prepared based on centrifugal spinning fibers includes a stress layer and a base layer, the stress layer is bonded to the base layer; the stress layer includes a plurality of transverse conductive fibers and two longitudinal conductive fibers, the two longitudinal conductive fibers are respectively connected to the left and right sides of all transverse conductive fibers, and all transverse conductive fibers are evenly distributed to form a grid-like structure; all the transverse conductive fibers and longitudinal conductive fibers are made of no less than one conductive wire, when used, because the prepared stress layer is formed by laying fibers, rather than a layer formed by slurry in the prior art, the fibers have high toughness, are not easy to break, and will not be delaminated, so that the overall sensor has strong stability and high stress detection sensitivity. Therefore, the stress layer of the present invention has high mechanical strength and good stability.

[0017] 2. In a flexible stress sensor prepared based on centrifugal spinning fiber of the present invention, the top of the driving outer cylinder is connected to the bottom of the connecting ring, the connecting ring is arranged in a circular plate, the side of the feed pipe is embedded in the top center of the arc plate, and a plurality of feed holes are opened at the bottom of the feed pipe. The spinneret moves centrifugally with the driving outer cylinder, and an insulation inner cylinder is arranged on the inner side of the driving outer cylinder, the top of the insulation inner cylinder is connected to the bottom of the insulation plate, and a partition is installed at the bottom center of the insulation plate. When used, the molten body is injected into the feed pipe, and then the driving outer cylinder is driven to rotate, so that the spinneret moves centrifugally. The molten body gathers at two discharge ports under the action of centrifugal force, and is thrown out from the discharge port to form conductive fibers. Then the conductive fibers are made into a grid-like stress layer, which is then placed on the base layer. In the process of centrifugal formation, since the cross-sections of the arc plate and the circular plate are triangular, the gap at the bottom is smaller, so that the molten body is always kept at the discharge port, and the centrifugal force can ensure that the molten body is always sufficient, thereby improving the mechanical strength of the conductive fiber. Therefore, the melt of the present invention is always sufficient and the spinning quality is high.

[0018] 3. In a flexible stress sensor prepared based on centrifugal spinning fiber of the present invention, a heat-insulating inner cylinder is arranged on the inner side of the driving outer cylinder, the top of the heat-insulating inner cylinder is connected to the bottom of the heat-insulating board, a partition is installed in the center of the bottom of the heat-insulating board, the bottom of the heat-insulating board is located on the left side of the partition and has a plurality of air inlet holes, and the bottom of the heat-insulating board is located on the right side of the partition and has a plurality of air extraction holes, and the hot air circulates through the air inlet holes, the cavity of the heat-insulating board, and the air extraction holes in turn. When used, while feeding, hot air is continuously input into the heat-insulating inner cylinder, and the hot air enters the heat-insulating board through the air inlet holes, and then the hot air is extracted from the air extraction holes to form a cycle, thereby ensuring the state of the molten liquid, avoiding condensation of the melt, and affecting normal spinning, thereby ensuring the uniformity of mixing, and will not cause uneven mixing due to cold, or even impossible spinning, thereby improving the spinning quality. Therefore, the melt of the present invention is always abundant and the spinning quality is high.

[0019] 4. In a flexible stress sensor based on centrifugal spinning fiber of the present invention, a partition is installed at the center of the bottom of the insulation board, and a plurality of air inlet holes are opened at the bottom of the insulation board on the left side of the partition, and a plurality of air extraction holes are opened at the bottom of the insulation board on the right side of the partition. The partition is arranged at the center of the insulation board, and all the air inlet holes and the air extraction holes are distributed in a ring shape with the partition as the center; all the air inlet holes and the air extraction holes are arranged symmetrically. When used, the ventilation holes improve the circulation of air in the insulation inner cylinder, and avoid vacuum in the insulation board or hot air in the insulation board when the exhaust device fails, thereby causing safety problems in the insulation inner cylinder and the insulation board. Therefore, the present invention is safe to use and the air circulation is smooth. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the present invention.

[0021] Figure 2 It is a schematic structural diagram of the centrifugal spinning device in the present invention.

[0022] Figure 3 It is a schematic structural diagram of the spinneret device in the present invention.

[0023] Figure 4 It is a side sectional view of the spinning device in the present invention.

[0024] Figure 5 It is a front cross-sectional view of the spinneret in the present invention.

[0025] Figure 6 It is a schematic structural diagram of the thermal insulation board in the present invention.

[0026] Figure 7 It is a structural schematic diagram of the feed pipe in the present invention.

[0027] Figure 8 It is a schematic structural diagram of the second annular plate in the present invention.

[0028] Fig. 9 It is a schematic structural diagram of the driving outer cylinder in the present invention.

[0029] In the figure: spinneret 1, discharge port 11, fixing ring 12, arc plate 13, circular plate 14, material holding chamber 15, stress layer 16, transverse conductive fiber 161, longitudinal conductive fiber 162, base layer 17, feed pipe 2, first annular plate 21, feed hole 22, insulation plate 3, cavity 31, air extraction hole 32, air inlet hole 33, insulation inner cylinder 4, drive outer cylinder 5, partition plate 6, ventilation hole 61, connecting ring 7, second annular plate 71, drive gear 8, collecting device 9. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0031] See also Figures 1 to 9 , a flexible stress sensor prepared based on centrifugal spinning fibers, the flexible stress sensor prepared based on centrifugal spinning fibers comprising a stress layer 16 and a base layer 17, the stress layer 16 being bonded to the base layer 17; The stress layer 16 includes a plurality of transverse conductive fibers 161 and two longitudinal conductive fibers 162. The two longitudinal conductive fibers 162 are respectively connected to the left and right sides of all the transverse conductive fibers 161. All the transverse conductive fibers 161 are evenly distributed to form a grid-like structure. All of the transverse conductive fibers 161 and the longitudinal conductive fibers 162 are made of at least one conductive thread.

[0032] The conductive yarn is made by centrifugal spinning. The melt in the centrifugal spinning includes a conductive solute and a conventional polymer. The conventional polymer is any one of PLA, PVA, PVP, and PTF, or a mixture of multiple thereof.

[0033] The centrifugal spinning is operated by the following equipment, including a spinning device 1, a feed pipe 2, a heat preservation plate 3, a heat preservation inner cylinder 4 and a driving outer cylinder 5; A collecting device 9 is provided on the outside of the spinning device 1; The spinning device 1 comprises an arc-shaped plate 13 with an arc-shaped top and a circular plate 14 with a flat bottom. The bottom of the arc-shaped plate 13 is connected to the top of the circular plate 14. A discharge port 11 is respectively provided at the left and right ends of the arc-shaped plate 13. A material holding cavity 15 is formed between the arc plate 13 and the circular plate 14, and the spacing of the material holding cavity 15 decreases from the center of the arc plate 13 to the surroundings; The top of the driving outer cylinder 5 is connected to the bottom of the connecting ring 7, the connecting ring 7 is arranged in the circular plate 14, the side of the feed pipe 2 is embedded in the top center of the arc plate 13, and a plurality of feed holes 22 are opened at the bottom of the feed pipe 2. The spinneret 1 performs centrifugal motion with the driving outer cylinder 5; The outer side of the driving outer cylinder 5 is sleeved with a driving gear 8, and the driving gear 8 is connected to the external driving mechanism; The inner side of the driving outer cylinder 5 is provided with an insulation inner cylinder 4, the top of the insulation inner cylinder 4 is connected to the bottom of the insulation board 3, a partition 6 is installed in the center of the bottom of the insulation board 3, a plurality of air inlet holes 33 are opened at the bottom of the insulation board 3 located on the left side of the partition 6, and a plurality of air extraction holes 32 are opened at the bottom of the insulation board 3 located on the right side of the partition 6, and the hot air circulates through the air inlet holes 33, the cavity 31 of the insulation board 3, and the air extraction holes 32 in sequence; There is a gap between the feed pipe 2 and the insulation board 3; The molten material in the material holding chamber 15 flows into the spinning device 1 through the material feeding hole 22 and is thrown out from the material discharging port 11 under the action of centrifugal force.

[0034] Two first annular plates 21 are arranged on the side of the feed pipe 2, and a fixing ring 12 is arranged on the top of the arc plate 13, and the fixing ring 12 is embedded in the gap between the two first annular plates 21; The feed pipe 2 does not perform centrifugal motion along with the driving outer cylinder 5 .

[0035] The diameter of the connecting ring 7 is the same as the diameter of the driving outer cylinder 5, and the upper end of the connecting ring 7 is located in the cavity of the spinning device 1; The inner wall of the connecting ring 7 is connected to the outer side of the heat-insulating inner cylinder 4 .

[0036] Two second annular plates 71 are arranged on the outer side of the connecting ring 7, and the circular plate 14 is clamped between the two second annular plates 71; The distance between the second annular plate 71 at the top and the heat preservation plate 3 is greater than the distance between the connecting ring 7 and the heat preservation plate 3 .

[0037] A plurality of ventilation holes 61 are sequentially opened on the side surface of the partition plate 6 from top to bottom, and the distance between two adjacent ventilation holes 61 is the same.

[0038] The partition plate 6 is arranged at the center of the heat preservation plate 3, and all the air inlet holes 33 and the air exhaust holes 32 are distributed in a ring shape with the partition plate 6 as the center; All the air inlet holes 33 are symmetrically arranged with respect to the air exhaust holes 32 .

[0039] The insulation plate 3 is a circular plate, and the centers of the insulation plate 3 and the feed pipe 2 are located on the same longitudinal axis; The diameter of the insulation board 3 is greater than the diameter of the feed pipe 2 .

[0040] The top of the heat-insulating inner cylinder 4 passes through the connecting ring 7 and is connected to the bottom of the heat-insulating plate 3 , and there is no contact between the heat-insulating plate 3 and the connecting ring 7 .

[0041] The supplementary description of the present invention is as follows: The conductive solute in the present invention is preferably one of metal wires, carbon fibers, and carbon nanotubes, or any combination thereof.

[0042] The feed pipe 2 in the present invention does not move with the spinneret 1, so that the feed pipe 2 can continuously feed and replenish the melt in real time, ensuring that the amount of melt at the discharge port 11 is always sufficient.

[0043] Embodiment 1: A flexible stress sensor prepared based on centrifugal spun fibers, the flexible stress sensor prepared based on centrifugal spun fibers comprising a stress layer 16 and a base layer 17, the stress layer 16 being bonded to the base layer 17; the stress layer 16 comprising a plurality of transverse conductive fibers 161 and two longitudinal conductive fibers 162, the two longitudinal conductive fibers 162 being respectively connected to the left and right sides of all the transverse conductive fibers 161, all the transverse conductive fibers 161 being evenly distributed to form a grid-like structure; all the transverse conductive fibers 161 and the longitudinal conductive fibers 162 are made of at least one conductive thread.

[0044] When used: the conductive wire is wound into a plurality of transverse conductive fibers 161 and longitudinal conductive fibers 162 , and then the plurality of transverse conductive fibers 161 and longitudinal conductive fibers 162 are combined to form a grid-like stress layer 16 , and then the stress layer 16 is pasted or printed on the base layer 17 .

[0045] Embodiment 2: Embodiment 2 is substantially the same as Embodiment 1, except that: A flexible stress sensor prepared based on centrifugal spinning fiber, the centrifugal spinning is operated by the following equipment, including a spinneret 1, a feed pipe 2, a heat preservation plate 3, a heat preservation inner cylinder 4 and a driving outer cylinder 5; a collecting device 9 is arranged on the outside of the spinneret 1; the spinneret 1 includes an arc-shaped plate 13 with an arc-shaped top and a circular plate 14 with a flat bottom, the bottom of the arc-shaped plate 13 is connected to the top of the circular plate 14, and a discharge port 11 is arranged at the left and right ends of the arc-shaped plate 13 respectively; the spacing between the arc-shaped plate 13 and the circular plate 14 decreases from the center of the arc-shaped plate 13 to the surrounding areas; the top of the driving outer cylinder 5 is connected to the bottom of the connecting ring 7, the connecting ring 7 is arranged through the circular plate 14, the side of the feed pipe 2 is embedded in the top center of the arc-shaped plate 13, and a plurality of feed holes 2 are opened at the bottom of the feed pipe 2 2. The spinneret 1 performs centrifugal motion along with the driving outer cylinder 5; a driving gear 8 is sleeved on the outer side of the driving outer cylinder 5, and the driving gear 8 is connected to the external driving mechanism; an insulating inner cylinder 4 is arranged on the inner side of the driving outer cylinder 5, and the top of the insulating inner cylinder 4 is connected to the bottom of the insulating plate 3, and a partition 6 is installed at the center of the bottom of the insulating plate 3, and a plurality of air inlet holes 33 are opened on the left side of the bottom of the insulating plate 3, and a plurality of air exhaust holes 32 are opened on the right side of the bottom of the insulating plate 3, and an exhaust device is arranged at the corresponding position of the air exhaust holes 32 in the insulating inner cylinder 4, and the hot air circulates through the air inlet holes 33, the cavity 31 of the insulating plate 3, and the air exhaust holes 32 in turn; there is a gap between the feeding pipe 2 and the insulating plate 3; the molten mass in the feeding pipe 2 flows into the spinneret 1 through the feeding hole 22 and is thrown out from the discharge port 11 under the action of centrifugal force.

[0046] During application: the molten body is injected into the feed pipe 2, and the molten body flows into the spinneret 1 through the feed hole 22, and then the driving device is started to drive the driving outer cylinder 5 to rotate, thereby driving the spinneret 1 to perform centrifugal movement. While feeding, hot air is continuously input into the heat-insulating inner cylinder 4, and the hot air enters the heat-insulating plate 3 through the air inlet hole 33, and then the hot air is extracted from the exhaust hole 32 to form a circulation, thereby maintaining the temperature of the molten body in the spinneret 1 to prevent the molten body from condensing and affecting the normal spinning. The molten body gathers at the two discharge ports 11 under the action of centrifugal force and is thrown out from the discharge port 11 to form conductive wire.

[0047] Embodiment 3: Embodiment 3 is substantially the same as Embodiment 1, except that: The diameter of the connecting ring 7 is the same as that of the driving outer cylinder 5, and the upper end of the connecting ring 7 is located in the cavity of the spinning device 1; the inner wall of the connecting ring 7 is connected to the outer side of the heat-insulating inner cylinder 4; two second annular plates 71 are arranged on the outer side of the connecting ring 7, and the circular plate 14 is clamped between the two second annular plates 71; the distance between the second annular plate 71 and the heat-insulating plate 3 at the top is greater than the distance between the connecting ring 7 and the heat-insulating plate 3.

[0048] When used: driving the outer cylinder 5 to rotate drives the two second annular plates 71 on the connecting ring 7 to rotate, so that the spinneret 1 performs centrifugal motion. During the centrifugal formation process, the centrifugal force can ensure that the molten body is always sufficient, thereby improving the mechanical strength of the conductive fiber.

[0049] Embodiment 4: Embodiment 4 is substantially the same as Embodiment 1, except that: A plurality of ventilation holes 61 are sequentially opened on the side of the partition 6 from top to bottom, and the spacing between two adjacent ventilation holes 61 is the same. The partition 6 is arranged at the center of the insulation plate 3, and all the air inlet holes 33 and the air exhaust holes 32 are distributed in a ring shape with the partition 6 as the center; all the air inlet holes 33 and the air exhaust holes 32 are symmetrically arranged, and the height of the partition 6 is less than the height of the insulation inner tube 4, and there is a gap between the front and rear sides of the partition 6 and the insulation inner tube 4; the top of the feed pipe 2 is penetrated by the arc plate 13, and the insulation plate 3 is a circular plate, and the center of the insulation plate 3 and the feed pipe 2 are located on the same longitudinal axis; the diameter of the insulation plate 3 is larger than the diameter of the feed pipe 2, and the top of the insulation inner tube 4 is connected to the bottom of the insulation plate 3 after passing through the connecting ring 7, and there is no contact between the insulation plate 3 and the connecting ring 7.

[0050] When in use: hot air is continuously input into the heat-insulating inner cylinder 4. Since an exhaust device is provided at the exhaust hole 32, the hot air enters from the air inlet 33 and is then extracted from the exhaust hole 32 by the exhaust device, so that the heat-insulating plate 3 can be insulated to ensure the state of the molten liquid, thereby ensuring the uniformity of mixing, and will not cause uneven mixing due to cold, or even make spinning impossible, thereby improving the spinning quality. At the same time, a plurality of ventilation holes 61 are provided on the partition 6 to further improve the circulation of air in the heat-insulating inner cylinder 4, and avoid safety problems of the heat-insulating inner cylinder 4 and the heat-insulating plate 3 when the exhaust device fails.

[0051] The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiment. Any equivalent modifications or changes made by ordinary technicians in this field based on the contents disclosed by the present invention should be included in the protection scope recorded in the claims.

Claims

1. A flexible stress sensor based on centrifugal spinning fiber, characterized in that: The flexible stress sensor prepared based on centrifugal spinning fibers comprises a stress layer (16) and a base layer (17), wherein the stress layer (16) is bonded to the base layer (17); The stress layer (16) comprises a plurality of transverse conductive fibers (161) and two longitudinal conductive fibers (162), the two longitudinal conductive fibers (162) being respectively connected to the left and right sides of all the transverse conductive fibers (161), and all the transverse conductive fibers (161) are evenly distributed to form a grid-like structure; All of the transverse conductive fibers (161) and the longitudinal conductive fibers (162) are made of at least one conductive thread.

2. A flexible stress sensor based on centrifugal spinning fiber according to claim 1, characterized in that: The conductive yarn is made by centrifugal spinning. The melt in the centrifugal spinning includes a conductive solute and a conventional polymer. The conventional polymer is any one of PLA, PVA, PVP, and PTF, or a mixture of multiple thereof.

3. A flexible stress sensor based on centrifugal spinning fiber according to claim 2, characterized in that: The centrifugal spinning is operated using the following equipment, including a spinning device (1), a feed pipe (2), a heat preservation plate (3), a heat preservation inner cylinder (4) and a driving outer cylinder (5); A collecting device (9) is provided on the outside of the spinning device (1); The spinning device (1) comprises an arc-shaped plate (13) with an arc-shaped top and a circular plate (14) with a flat bottom, the bottom of the arc-shaped plate (13) is connected to the top of the circular plate (14), and a discharge port (11) is respectively provided at the left and right ends of the arc-shaped plate (13); A material holding cavity (15) is formed between the arc-shaped plate (13) and the circular plate (14), and the spacing of the material holding cavity (15) decreases from the center of the arc-shaped plate (13) to the periphery; The top of the driving outer cylinder (5) is connected to the bottom of the connecting ring (7), the connecting ring (7) is arranged through the circular plate (14), the side of the feed pipe (2) is embedded in the top center of the arc plate (13), and a plurality of feed holes (22) are opened at the bottom of the feed pipe (2), and the spinneret device (1) performs centrifugal movement along with the driving outer cylinder (5); A driving gear (8) is sleeved on the outer side of the driving outer cylinder (5), and the driving gear (8) is connected to an external driving mechanism; An insulating inner cylinder (4) is arranged on the inner side of the driving outer cylinder (5); the top of the insulating inner cylinder (4) is connected to the bottom of the insulating plate (3); a partition (6) is installed in the center of the bottom of the insulating plate (3); a plurality of air inlet holes (33) are opened at the bottom of the insulating plate (3) on the left side of the partition (6); a plurality of air exhaust holes (32) are opened at the bottom of the insulating plate (3) on the right side of the partition (6); and hot air circulates through the air inlet holes (33), the cavity (31) of the insulating plate (3), and the air exhaust holes (32) in sequence; There is a gap between the feed pipe (2) and the insulation plate (3); The molten material in the material holding chamber (15) flows into the spinneret (1) through the feed hole (22) and is thrown out from the discharge port (11) under the action of centrifugal force.

4. A flexible stress sensor based on centrifugal spinning fiber according to claim 3, characterized in that: Two first annular plates (21) are arranged on the side of the feed pipe (2), a fixing ring (12) is arranged on the top of the arc-shaped plate (13), and the fixing ring (12) is embedded in the gap between the two first annular plates (21); The feed pipe (2) does not perform centrifugal motion along with the driving outer cylinder (5).

5. The flexible stress sensor prepared based on centrifugal spinning fiber according to claim 3, characterized in that: The diameter of the connecting ring (7) is the same as the diameter of the driving outer cylinder (5), and the upper end of the connecting ring (7) is located in the cavity of the spinning device (1); The inner wall of the connecting ring (7) is connected to the outer side of the heat-insulating inner cylinder (4).

6. A flexible stress sensor based on centrifugal spinning fiber according to claim 5, characterized in that: Two second annular plates (71) are arranged on the outer side of the connecting ring (7), and the circular plate (14) is clamped between the two second annular plates (71); The distance between the second upper annular plate (71) and the heat-insulating plate (3) is greater than the distance between the connecting ring (7) and the heat-insulating plate (3).

7. The flexible stress sensor prepared based on centrifugal spinning fiber according to claim 3, characterized in that: A plurality of ventilation holes (61) are sequentially provided on the side surface of the partition plate (6) from top to bottom, and the spacing between two adjacent ventilation holes (61) is the same.

8. The flexible stress sensor prepared based on centrifugal spinning fiber according to claim 7, characterized in that: The partition plate (6) is arranged at the center of the heat-insulating plate (3), and all the air inlet holes (33) and the air exhaust holes (32) are distributed in a ring shape with the partition plate (6) as the center; All the air inlet holes (33) and the air extraction holes (32) are symmetrically arranged.

9. The flexible stress sensor prepared based on centrifugal spinning fiber according to claim 3, characterized in that: The insulation plate (3) is a circular plate, and the centers of the insulation plate (3) and the feed pipe (2) are located on the same longitudinal axis; The diameter of the insulation plate (3) is greater than the diameter of the feed pipe (2).

10. A flexible stress sensor based on centrifugal spinning fiber according to claim 9, characterized in that: The top of the heat-insulating inner cylinder (4) passes through the connecting ring (7) and is connected to the bottom of the heat-insulating plate (3), and there is no contact between the heat-insulating plate (3) and the connecting ring (7).

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