Flexible resistive strain sensor based on wrinkled interwoven structure and weaving method thereof

Abstract

The present application discloses a flexible resistive strain sensor based on a wrinkled interwoven structure and a weaving method thereof, which relate to the field of intelligent wearable devices. The flexible resistive strain sensor uses elastic conductive yarns and inelastic conductive yarns with different tensile properties to contact each other to form a loop, and adopts an interwoven pattern in which loose tissues and tight tissues with different shrinkage properties are arranged in an intricate manner, so as to produce a differential shrinkage effect on the surface of the fabric to form a wrinkled interwoven structure. The flexible resistive strain sensor has a negative Poisson's ratio effect, and expands outward in the warp and weft directions at the same time. When stretched, the spacing between the conductive yarns increases, so that the contact resistance between the conductive yarns increases, forming an effect of unidirectional change of strain and resistance, thereby realizing the strain sensing characteristics of the wrinkled fabric, and having an excellent and high-precision sensing function.

Description

Technical Field

[0001] The present application relates to the field of intelligent wearable devices, and in particular to a flexible resistive strain sensor based on a wrinkled interwoven structure and a weaving method thereof. Background Art

[0002] With the advancement of science and technology and the improvement of people's living standards, the development of smart wearable devices has been promoted. Among them, resistive flexible strain sensors, as one of the core components of wearable devices, can convert the strain of materials into resistance signal output, and have broad market prospects in the fields of medical care, health monitoring, signal recognition, etc.

[0003] Among various resistive flexible strain sensors, fabric-based flexible resistive strain sensors have been widely used in smart wearable devices because of their unique weaving structure, softness, good air and moisture permeability, and good biocompatibility and low cost. However, due to the positive Poisson's ratio of traditional fabrics, the distance between yarns increases when the fabric stretches in the stretching direction, and decreases when the fabric contracts perpendicular to the stretching direction. As a result, the existing fabric-based flexible resistive strain sensors have low sensitivity, a small strain monitoring range, and even a non-monotonic response of resistance to strain, which limits their application prospects. At the same time, it was found through searches that the existing fabric-based resistive strain sensors are mostly made by combining conductive materials with fabric substrates through soaking and drying, screen printing, vacuum filtration, high-temperature carbonization, etc., which have problems such as long production process, easy detachment of conductive materials from fabrics, and poor durability of sensors.

[0004] For example, Li et al. (Li Yuan, Zhang Mi, Zhao Tingting, et al. Flexible and breathable strain sensor with high performance based on MXene / nylon fabricnetwork[J]. Sensors and Actuators A: Physical, 2020, 315112192.) coated MXene on nylon fabric by soaking and drying to make a resistive strain sensor. However, due to the positive Poisson's ratio of nylon fabric, the resistance responded non-monotonicly with strain, and its effective strain monitoring range was only 20%; Zheng et al. (YanjunZheng, Li Yilong, Zhou Yujie, et al. High-Performance Wearable Strain SensorBased on Graphene / Cotton Fabric with High Durability and Low Detection Limit[J]. ACS Applied Materials&Interfaces, 2020, 12(1): 1474-1485.) After multiple impregnation processes, graphene nanosheets were deposited on plain cotton fabric, and then the fabric was encapsulated with polydimethylsiloxane. The sensor has a tensile strain range of 0~75%, but its sensitivity is only 2.49.

[0005] The patent (CN108680095A) provides a method for preparing a flexible strain sensor based on carbon nanofiber yarn fabric. The patent prepares polyacrylonitrile nanofiber yarn through an electrospinning process, then prepares the fabric through a weaving process, and obtains a flexible strain sensor through oxidation, high-temperature carbonization and elastic polymer encapsulation. However, this method requires complex equipment and processes, a long production process, and the air and moisture permeability of the fabric after encapsulation is poor, which limits the application scenarios of the prepared sensor.

[0006] The patent (CN107385623A) provides a flexible strain sensing woven fabric and its manufacturing process. The patent uses elastic conductive yarn with strain sensing function as weft floating yarn to be fixed on the surface of non-conductive elastic woven fabric to form a floating pattern. The structure is simple and soft. However, since the conductive yarn only forms an interlacing point with the weft yarn of the non-conductive elastic woven fabric at the weft edge of the floating pattern, the conductive yarn exists in a long floating line state and the structure is unstable. Therefore, there are problems such as easy snagging, different degrees of strain deformation between the floating pattern and the elastic fabric base, and when stretched along the weft direction, the fabric shrinks in the warp direction, the spacing between the conductive long floating lines decreases, and the contact resistance decreases. However, the resistance of the elastic conductive yarn itself increases, resulting in a decrease in the sensitivity of the sensor. Summary of the invention

[0007] In view of the above problems and technical requirements, the applicant has proposed a flexible resistive strain sensor based on a wrinkled interwoven structure and a weaving method thereof. The technical solution of the present application is as follows:

[0008] A flexible resistive strain sensor based on a wrinkled interwoven structure comprises a fabric formed by interweaving a plurality of parallel conductive warp yarns and a plurality of parallel conductive weft yarns, and conductive wires connected to both ends of the fabric; the conductive yarns constituting the conductive warp yarns comprise elastic conductive yarns and inelastic conductive yarns, the conductive yarns constituting the conductive weft yarns comprise elastic conductive yarns and inelastic conductive yarns, the elastic conductive yarns and inelastic conductive yarns are interwoven to form tight weave points and loose weave points, the loose weave points and tight weave points with different shrinkage properties interact with each other and allow the fabric to form a wrinkled interwoven structure with a concave-convex effect.

[0009] A further technical solution is that the elastic conductive yarns and the inelastic conductive yarns in each direction are arranged at intervals according to a predetermined arrangement ratio.

[0010] A further technical solution is that the tight weave points and the loose weave points in the fabric weave are arranged alternately in the longitude direction and the latitude direction respectively.

[0011] A further technical solution is that, in one weaving cycle of the fabric weave, the difference in the number of warp weaving points and weft weaving points of each conductive warp yarn and conductive weft yarn is within a predetermined range.

[0012] Its further technical solution is that in the process of stretching the fabric, the conductive warp yarns and the conductive weft yarns are rearranged and tend to be straightened, the spacing between the conductive yarns increases, and the fabric exhibits a negative Poisson's ratio effect until the bent conductive yarns are completely straightened and parallel. In the process of stretching the fabric, the dimensions of the fabric in the warp and weft directions become larger, and the resistance value of the fabric is positively correlated with the strain caused by the stretching.

[0013] A further technical solution is that the yarn material used for each conductive warp yarn is conductive filament or staple yarn, and the conductive filament includes conductive monofilament and conductive multifilament; the yarn material used for each conductive weft yarn is conductive filament or staple yarn, and the conductive filament includes conductive monofilament and conductive multifilament.

[0014] A further technical solution is that the yarn materials used for all the conductive warp yarns and all the conductive weft yarns are conductive monofilaments.

[0015] Its further technical solution is that the yarn material used for each elastic conductive yarn constituting the conductive warp yarn or the conductive weft yarn is silver-plated high-elastic nylon conductive monofilament, silver-plated high-elastic nylon conductive multifilament, conductive polymer and polyurethane composite conductive monofilament, conductive polymer and polyurethane composite conductive multifilament, carbon-based conductive material and polyurethane composite conductive monofilament, carbon-based conductive material and polyurethane composite conductive multifilament, Ti3C2 cotton-spandex core-covered yarn or wrapped yarn; the yarn material used for each inelastic conductive yarn constituting the conductive warp yarn or the conductive weft yarn is silver-plated or nickel-plated conductive monofilament, silver-plated or nickel-plated conductive multifilament, conductive polymer and polyamide composite conductive monofilament, conductive polymer and polyamide composite conductive multifilament, carbon-based conductive material and polyamide composite conductive monofilament, carbon-based conductive material and polyamide composite conductive multifilament or stainless steel chopped yarn.

[0016] A weaving method for a flexible resistive strain sensor based on a wrinkled interwoven structure, the weaving method comprising:

[0017] Preparing a plurality of elastic conductive yarns and inelastic conductive yarns arranged in parallel along the longitude direction to form the conductor warp yarns, and a plurality of elastic conductive yarns and inelastic conductive yarns arranged in parallel along the latitude direction to form the conductive weft yarns;

[0018] According to the design method of the wrinkle structure, the operations of winding, warping, sizing, warp drawing and weaving are completed to obtain a fabric formed by interweaving conductive warp yarns and conductive weft yarns, wherein the obtained fabric structure includes tight structure points and loose structure points, and the loose structure points and tight structure points with different shrinkage properties interact with each other to form a wrinkle interweaving structure with a concave-convex effect on the fabric;

[0019] The fabric is then tidied and wires are connected to both ends of the fabric to obtain a flexible resistive strain sensor.

[0020] Its further technical solution is that the method for finishing the fabric after completion includes:

[0021] The fabric is subjected to steaming and heat setting treatments to eliminate the internal stress in the fabric, so that the elastic conductive yarn in the fabric fully shrinks and drives the non-elastic conductive yarn to bulge.

[0022] The beneficial technical effects of this application are:

[0023] The present application discloses a flexible resistive strain sensor based on a wrinkled interwoven structure and a weaving method thereof. The flexible resistive strain sensor uses elastic conductive yarns and inelastic conductive yarns with different tensile properties to contact and form a loop, and adopts an interwoven pattern in which loose tissues and tight tissues with different shrinkage properties are arranged in an intricate manner, so as to produce a differential shrinkage effect on the fabric surface, making the fabric surface uneven, with an obvious uneven wrinkle effect and a strong three-dimensional sense. Based on the wrinkling effect of the fabric tissue, the flexible resistive strain sensor will expand in the transverse direction when stretched longitudinally; conversely, when the longitudinal shrinkage forms a wrinkled surface, the transverse direction will also shrink, with a negative Poisson's ratio effect, so that the warp and weft directions of the flexible resistive strain sensor expand outward at the same time, the spacing between the conductive yarns increases, so that the contact resistance between the conductive yarns increases, forming an effect of unidirectional change of strain and resistance, thereby realizing the strain sensing characteristics of the wrinkled fabric, and having an excellent and high-precision sensing function.

[0024] In addition, the flexible resistive strain sensor is based on the integral weaving of wrinkled fabric and has a stable structure. Therefore, the flexible resistive strain sensor has good softness, breathability, moisture permeability, biocompatibility, durability and low cost. It can convert the strain on the fabric into a resistance signal output and has broad market prospects in the fields of medical care, health monitoring, signal recognition, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the interweaving of conductive warp yarns and conductive weft yarns in an example of the present application.

[0026] Figure 2 This is a schematic diagram of the negative Poisson's ratio effect of wrinkling in which the flexible resistive strain sensor of the present application has a small size before stretching and both the length and width become larger after stretching in one example.

[0027] Figure 3 It is a comparison graph of the resistance change rate of the flexible resistive strain sensor of the present application and the traditional flexible resistive strain sensor as the strain is applied.

[0028] Figure 4 It is a flow chart of a method for weaving a flexible resistive strain sensor according to an embodiment of the present application.

[0029] Figure 5 The diagram is a basic structure designed based on the rotation method in an example and a structure diagram of the wrinkled fabric obtained after rotation.

[0030] Figure 6 The diagram is a basic structure designed based on the sequencing method and a structure diagram of a wrinkled fabric obtained after sequencing in an example.

[0031] Figure 7-9 This is a picture of a fabric in a weaving example. Figure 7 For the weaving diagram, Figure 8 For the pattern, Fig. 9 For the organizational chart. DETAILED DESCRIPTION

[0032] The specific implementation of the present application is further described below in conjunction with the accompanying drawings.

[0033] This application discloses a flexible resistive strain sensor based on a wrinkled interwoven structure. Please refer to Figure 1 The flexible resistive strain sensor includes a fabric formed by interweaving a plurality of conductive warp yarns 1 arranged in parallel along the longitude direction and a plurality of conductive weft yarns 2 arranged in parallel along the latitude direction, and the longitude direction and the latitude direction are perpendicular to each other. In addition, the flexible resistive strain sensor also includes wires connected to both ends of the fabric. Figure 1 The wires connecting the two ends of the fabric are not shown.

[0034] The conductive warp yarn 1 and the conductive weft yarn 2 are both made of conductive yarn. The conductive yarn constituting the conductive warp yarn 1 includes elastic conductive yarn and inelastic conductive yarn, such as Figure 1 As shown, the elastic conductive yarn constituting the conductive warp yarn 1 is indicated by a solid line, and the inelastic conductive yarn constituting the conductive warp yarn 1 is indicated by a dotted line. The conductive yarn constituting the conductive weft yarn 2 includes an elastic conductive yarn and an inelastic conductive yarn. Similarly, the elastic conductive yarn constituting the conductive weft yarn 2 is indicated by a solid line, and the inelastic conductive yarn constituting the conductive weft yarn 2 is indicated by a dotted line.

[0035] Regardless of the longitude or latitude direction, the elastic conductive yarn and the inelastic conductive yarn are arranged at intervals according to a predetermined arrangement ratio, the predetermined arrangement ratio can be customized, and the number of elastic conductive yarns can be greater than, less than or equal to the number of inelastic conductive yarns. When the elastic conductive yarn and the inelastic conductive yarn are arranged at intervals according to a predetermined arrangement ratio of M:N, it means that when the elastic conductive yarn and the inelastic conductive yarn are arranged at intervals, N inelastic conductive yarns are arranged for every M elastic conductive yarns. Figure 1 Taking the example of arranging the elastic conductive yarn and the inelastic conductive yarn at intervals according to a predetermined arrangement ratio of 1:1, other common predetermined arrangement ratios of the elastic conductive yarn and the inelastic conductive yarn may be, for example, 2:2, 2:1, 1:2, etc.

[0036] The elastic conductive yarn and the inelastic conductive yarn are interwoven to form tight weave points and loose weave points. At the tight weave points with shorter floats, the conductive yarn is subjected to greater binding force, shrinks less, and the fabric surface is smooth. The long floats at the loose weave points are affected by the tight weave points with tighter structures, causing the fabric surface to bulge. Therefore, the loose weave points and tight weave points with different shrinkage properties interact with each other and form a wrinkled interwoven structure with a concave-convex effect on the fabric. Please refer to Figure 2 When the flexible resistive strain sensor is not stretched, the fabric has the following characteristics: Figure 2 The small-sized wrinkled interwoven structure 3 is provided, and the two ends of the fabric are connected with the conductive wire 5.

[0037] The tight points and loose points in the fabric weave are staggered in the longitude and latitude directions, respectively, so as to avoid a large number of warp points or weft points being concentrated together, so as not to affect the wrinkling effect. In addition, the floating lines of the conductive warp yarn and the conductive weft yarn should not be too long, and obvious twill, stripes or other patterns should not appear, so as not to affect the wrinkling effect.

[0038] In addition, in one weaving cycle of the fabric weave, the difference in the number of warp weaving points and weft weaving points of each conductive warp yarn and conductive weft yarn is within a predetermined range, that is, the number of warp weaving points and weft weaving points is as consistent as possible, to prevent the conductive warp yarn from having too large a difference in weaving shrinkage, which affects the clarity of the shed and the appearance of the fabric.

[0039] Based on the structure of the fabric of the flexible resistive strain sensor, the conductive warp yarn 1 and the conductive weft yarn 2 of the raised part of the fabric deviate from their original positions, and the conductive warp yarn 1 and the conductive weft yarn 2 are arranged in a bent manner. During the stretching process of the fabric, the conductive warp yarn 1 and the conductive weft yarn 2 are rearranged and tend to straighten, the spacing between the conductive yarns increases, and the fabric expands in both the horizontal and vertical directions. Please refer to Figure 2 When the flexible resistive strain sensor is stretched, the fabric has the following characteristics: Figure 2 The length and width of the wrinkled interwoven structure 4 are enlarged, and the structure of the conductors 5 connected at both ends of the fabric remains unchanged. Therefore, the fabric surface has a negative Poisson's ratio effect until the bent conductive yarns are completely straightened and parallel. During the stretching process of the fabric, the dimensions of the fabric in the warp and weft directions are enlarged, and the resistance value of the fabric is positively correlated with the strain caused by the stretching. Please refer to Figure 3 The curves showing the change in resistance rate of the flexible resistive strain sensor made of the fabric tissue of the present application and the flexible resistive strain sensor made of conventional fabric tissue as the strain is applied are shown.

[0040] The yarn material used in each conductive warp yarn is conductive filament or staple yarn, and the conductive filament includes conductive monofilament and conductive multifilament. The yarn material used in each conductive weft yarn is conductive filament or staple yarn, and the conductive filament includes conductive monofilament and conductive multifilament.

[0041] Furthermore, considering that the contact between filaments or fibers during the stretching of the conductive multifilament or staple yarn is closer, which is opposite to the sensing mechanism of the increase in yarn spacing during the stretching of the wrinkled fabric, in order to make the flexible resistive strain sensor have better sensitivity, the yarn materials used for all conductive warp yarns and all conductive weft yarns are conductive monofilaments.

[0042] In one embodiment, the yarn material used for each elastic conductive yarn constituting the conductive warp yarn or the conductive weft yarn is silver-plated high-elastic nylon conductive monofilament, silver-plated high-elastic nylon conductive multifilament, conductive polymer and polyurethane composite conductive monofilament, conductive polymer and polyurethane composite conductive multifilament, carbon-based conductive material and polyurethane composite conductive monofilament, carbon-based conductive material and polyurethane composite conductive multifilament, Ti3C2 cotton-spandex core-spun yarn or wrapped yarn. Among them, silver-plated high-elastic nylon conductive monofilament, conductive polymer and polyurethane composite conductive monofilament, carbon-based conductive material and polyurethane composite conductive monofilament are conductive monofilaments. Silver-plated high-elastic nylon conductive multifilament, conductive polymer and polyurethane composite conductive multifilament, carbon-based conductive material and polyurethane composite conductive multifilament are conductive multifilaments. Ti3C2 cotton-spandex core-spun yarn and wrapped yarn are short fiber yarns.

[0043] In one embodiment, the yarn material used for each non-elastic conductive yarn constituting the conductive warp yarn or the conductive weft yarn is a silver-plated or nickel-plated conductive monofilament, a silver-plated or nickel-plated conductive multifilament, a conductive polymer and polyamide composite conductive monofilament, a conductive polymer and polyamide composite conductive multifilament, a carbon-based conductive material and polyamide composite conductive monofilament, a carbon-based conductive material and polyamide composite conductive multifilament, or a stainless steel chopped yarn. Among them, the silver-plated or nickel-plated conductive monofilament, the conductive polymer and polyamide composite conductive monofilament, and the carbon-based conductive material and polyamide composite conductive monofilament are conductive monofilaments. The silver-plated or nickel-plated conductive multifilament, the conductive polymer and polyamide composite conductive multifilament, and the carbon-based conductive material and polyamide composite conductive multifilament are conductive multifilaments. The stainless steel chopped yarn is a staple yarn.

[0044] The present application also discloses a weaving method of a flexible resistive strain sensor based on a wrinkled interwoven structure, the manufacturing method comprises the following steps, please refer to Figure 4 The flowchart shown:

[0045] Step 1: prepare a plurality of elastic conductive yarns and inelastic conductive yarns arranged in parallel along the longitude direction to form the conductor warp yarns, and a plurality of elastic conductive yarns and inelastic conductive yarns arranged in parallel along the latitude direction to form the conductive weft yarns.

[0046] When preparing the conductive warp yarns and the conductive weft yarns arranged in parallel, the elastic conductive yarns and the non-elastic conductive yarns are arranged at intervals according to a predetermined arrangement ratio.

[0047] Since the selected conductive yarns include elastic conductive yarns and inelastic conductive yarns, the loom used must have a weft selection device to ensure smooth weft insertion of multiple conductive yarns, and use double weaving beam weaving to reasonably control the tension of the elastic conductive yarn and the inelastic conductive yarn.

[0048] Step 2, completing the operations of winding, warping, sizing, warp stringing and weaving according to the design method of the wrinkle structure to obtain a fabric formed by interweaving conductive warp yarns and conductive weft yarns.

[0049] The obtained fabric structure includes tight tissue points and loose tissue points. The loose tissue points and tight tissue points with different shrinkage properties interact with each other and make the fabric form a wrinkled interwoven structure with a concave-convex effect.

[0050] The wrinkle tissue design method used includes any one of the rotation method, sequence adjustment method, comprehensive design method, point addition method and transfer method. In one example, the basic tissue designed based on the rotation method is as follows Figure 5 As shown in (a) in Figure 5 The basic structure shown in (a) is rotated 90° counterclockwise and four pieces are combined to form a fabric structure as shown in FIG. Figure 5 In another embodiment, based on the sequence adjustment method, as shown in (b) Figure 5 As shown in (6) in ↗Based on the fabric structure, the fabric structure is drawn with the conductive warp yarn arrangement order of 1, 8, 3, 10, 5, 8, 3, 6, 1, 4. Figure 6 As shown in (b) in . Figure 5-9 Black boxes represent warp points and white boxes represent weft points.

[0051] Step 3, finishing the fabric after completion, and connecting wires at both ends of the fabric to obtain a flexible resistive strain sensor. This includes: steaming and heat setting the fabric to eliminate the internal stress in the fabric structure, so that the elastic conductive yarn in the fabric fully shrinks and drives the non-elastic conductive yarn to bulge, and the wrinkles have a strong three-dimensional sense. In addition, the heat setting treatment can also improve the durability of the flexible resistive strain sensor, so that the fabric obtains dimensional stability, while maintaining the three-dimensional style of the uneven surface of the fabric.

[0052] In one weaving example, the weaving method comprises the following steps:

[0053] (1) Prepare conductive yarn:

[0054] Elastic conductive yarn: Place the uniformly mixed carbon nanotubes and polyurethane powder (carbon nanotube mass fraction is 3%) into a melt spinning experimental machine, set the extrusion temperature to 180-185°C, control the extrusion speed, and spin a conductive monofilament with a linear density of 13tex.

[0055] Prepare non-elastic conductive yarn: select polyester silver-plated conductive monofilament with a linear density of 13tex.

[0056] If the fabric width is too narrow, the fabric will not wrinkle obviously after heat setting, so the width is set to 152cm. After the fabric wrinkles, the warp and weft density increases, so the density of the fabric cannot be too high, otherwise it will affect the wrinkling effect. The density of the fabric cannot be too low, otherwise the fabric is prone to defects. Therefore, the warp and weft density is selected as 360 / 10cm×300 / 10cm.

[0057] (2) Winding: The winding process of non-elastic conductive yarn is the same as that of conventional yarn. For elastic conductive yarn, it is necessary to ensure that the bobbin is well formed and the yarn is as straight as possible, so the winding tension is increased by 15%.

[0058] (3) Warping: Use a batch warping machine to arrange the carbon nanotube / polyurethane monofilaments and polyester silver-plated monofilaments onto different warp beams. The warping process for non-elastic conductive yarns is the same as that for conventional yarns. Elastic conductive yarns use a low-speed, high-tension process.

[0059] (4) Sizing: The sizing process of non-elastic conductive yarn is the same as that of conventional yarn. For elastic conductive yarn, attention should be paid to protecting the elasticity of the yarn, controlling the tension in different zones, and setting the speed to be slow. The sizing rate should be controlled at 8%~9%, and the sizing temperature should be controlled at 90±1℃.

[0060] (5) Warp threading: The conductive yarn is threaded in Figure 7 The heald wires shown in the drawing are inserted into the corresponding heald frames in sequence, with 4 heald wires inserted into each reed.

[0061] (6) Weaving: According to Figure 8 The pattern diagram shown sets the order of lifting the harness. Fig. 9 The number "1" indicates elastic conductive yarn, and "2" indicates inelastic conductive yarn. The weft selection is set reasonably. The process of inelastic conductive yarn is the same as that of conventional yarn. The setting of the tension of elastic conductive yarn is similar to the previous process. The yarn tension is set larger and it must be uniform. The five movements of opening, weft insertion, weft beating, curling and warp feeding are carried out in sequence to weave the fabric.

[0062] (7) Finishing: After the fabric is off the machine, it is desized by padding under tension-free and low-temperature conditions. After steaming for 25 minutes, it is heat-set, with a setting time of 1 to 2 minutes, a temperature of 95 to 100°C, and an overfeed of 3% to 4% for the heat-setting machine.

[0063] The above is only a preferred embodiment of the present application, and the present application is not limited to the above embodiments. It is understood that other improvements and changes directly derived or associated by those skilled in the art without departing from the spirit and concept of the present application should be considered to be included in the protection scope of the present application.

Claims

1. A flexible resistive strain sensor based on a wrinkled interwoven structure, characterized in that: The flexible resistive strain sensor comprises a fabric formed by interweaving a plurality of parallel conductive warp yarns and a plurality of parallel conductive weft yarns, and wires connected to both ends of the fabric; the conductive yarns constituting the conductive warp yarns comprise elastic conductive yarns and inelastic conductive yarns, the conductive yarns constituting the conductive weft yarns comprise elastic conductive yarns and inelastic conductive yarns, the elastic conductive yarns and inelastic conductive yarns are interwoven to form tight tissue points and loose tissue points, the loose tissue points and tight tissue points with different shrinkage properties interact with each other and make the fabric form a wrinkled interwoven structure with a concave-convex effect; in the process of stretching the fabric, the conductive warp yarns and the conductive weft yarns are rearranged and tend to straighten, the spacing between the conductive yarns increases, the fabric exhibits a negative Poisson's ratio effect until the bent conductive yarns are completely straightened and parallel, in the process of stretching the fabric, the dimensions of the fabric in the warp and weft directions increase, and the resistance value of the fabric is positively correlated with the strain generated by the stretching.

2. The flexible resistive strain sensor according to claim 1, characterized in that: The elastic conductive yarns and the non-elastic conductive yarns in each direction are arranged at intervals according to a predetermined arrangement ratio.

3. The flexible resistive strain sensor according to claim 1, characterized in that: The tight and loose points in the fabric are arranged alternately in the longitude and latitude directions respectively.

4. The flexible resistive strain sensor according to claim 1, characterized in that: In one weaving cycle of the fabric weave, the difference in the number of warp weaving points and the number of weft weaving points of each conductive warp yarn and conductive weft yarn is within a predetermined range.

5. The flexible resistive strain sensor according to claim 1, characterized in that: The yarn material used for each conductive warp yarn is conductive filament or short fiber yarn, and the conductive filament includes conductive monofilament and conductive multifilament; The yarn material used for each conductive weft yarn is conductive filament yarn or short fiber yarn, and the conductive filament yarn includes conductive monofilament yarn and conductive multifilament yarn.

6. The flexible resistive strain sensor according to claim 5, characterized in that: The yarn materials used for all conductive warp yarns and all conductive weft yarns are conductive monofilaments.

7. The flexible resistive strain sensor according to claim 5, characterized in that: The yarn material used for each elastic conductive yarn constituting the conductive warp yarn or the conductive weft yarn is silver-plated high-elastic nylon conductive monofilament, silver-plated high-elastic nylon conductive multifilament, conductive polymer and polyurethane composite conductive monofilament, conductive polymer and polyurethane composite conductive multifilament, carbon-based conductive material and polyurethane composite conductive monofilament, carbon-based conductive material and polyurethane composite conductive multifilament, Ti3C2 cotton-spandex core-spun yarn or wrapped yarn; The yarn material used for each non-elastic conductive yarn constituting the conductive warp yarn or the conductive weft yarn is silver-plated or nickel-plated conductive monofilament, silver-plated or nickel-plated conductive multifilament, conductive polymer and polyamide composite conductive monofilament, conductive polymer and polyamide composite conductive multifilament, carbon-based conductive material and polyamide composite conductive monofilament, carbon-based conductive material and polyamide composite conductive multifilament or stainless steel chopped yarn.

8. A weaving method for a flexible resistive strain sensor based on a wrinkled interwoven structure, the weaving method being used to weave a flexible resistive strain sensor based on a wrinkled interwoven structure as claimed in any one of claims 1 to 7, characterized in that: The weaving method comprises: Preparing a plurality of elastic conductive yarns and inelastic conductive yarns arranged in parallel along the longitude direction to form the conductor warp yarns, and a plurality of elastic conductive yarns and inelastic conductive yarns arranged in parallel along the latitude direction to form the conductive weft yarns; According to the design method of the wrinkle structure, winding, warping, sizing, warp drawing and weaving are completed to obtain a fabric formed by interweaving conductive warp yarns and conductive weft yarns, wherein the obtained fabric structure includes tight structure points and loose structure points, and the loose structure points and tight structure points with different shrinkage properties interact with each other to form a wrinkle interweaving structure with a concave-convex effect on the fabric; The fabric is then tidied and wires are connected to both ends of the fabric to obtain a flexible resistive strain sensor.

9. The weaving method according to claim 8, characterized in that: The finishing of the fabric after completion comprises: The fabric is subjected to steaming treatment and heat setting treatment to eliminate the internal stress in the fabric, so that the elastic conductive yarn in the fabric is fully retracted and drives the non-elastic conductive yarn to bulge.

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