Three-dimensional curved surface capacitive sensor and weaving method thereof

Abstract

The invention relates to a three-dimensional curved surface capacitive sensor and a weaving method thereof. The weaving method comprises the following steps: modeling the shape of the three-dimensional curved surface capacitive sensor into a three-dimensional curved surface grid; converting the three-dimensional curved surface grid into weaving information readable by a weaving device; generating a control command according to the weaving information, and weaving the three-dimensional curved surface capacitive sensor by taking the conductive warps and the conductive wefts as fabrics; each of the conductive warps and the conductive wefts comprises a bendable wire core and an insulating layer wrapping the wire core; and one or more conductive warps are connected in parallel to form a driving channel, and one or more conductive wefts are connected in parallel to form an induction channel. Capacitance nodes are formed at the crossed and overlapped positions of the driving channels and the sensing channels and used for forming stray capacitance with the living body to detect approaching of the living body. And the capacitor node is used for detecting a pressure value when the insulating layer is deformed due to pressure. By means of the weaving method, the capacitive sensor can be accurately attached to the curved surface of the target, and accurate mapping of sensing signals in the three-dimensional space is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of sensors, and in particular to a three-dimensional curved surface capacitance sensor and a weaving method of the three-dimensional curved surface capacitance sensor. Background Art

[0002] Bio-proximity sensors and pressure sensors are increasingly being used in the field of human-computer interaction. Especially in the fields of biomedicine, motion monitoring and other human-computer interaction technologies, there is a growing demand for real-time monitoring of biological proximity, detection of force on the sensor surface and quantification of force magnitude.

[0003] Traditional bio-proximity sensors and pressure sensors are usually designed and manufactured separately. Proximity sensors are mainly used to detect the proximity distance of the bio-proximity, while pressure sensors are used to measure the pressure value on the sensor surface. However, this separation design increases the size of the sensor and makes the structure complex. This sensor is easily damaged when twisted or pulled, and is not suitable for use when the sensor needs to cover a large area or in flexible wearable devices.

[0004] At the same time, general sensor products are two-dimensional planar structures, which cannot be accurately laid on complex three-dimensional free-form surfaces, nor can they realize the distribution of signal sensor arrays on three-dimensional free-form surfaces. Summary of the invention

[0005] Based on this, it is necessary to provide a three-dimensional curved surface capacitive sensor and a weaving method thereof that can resist damage during twisting or pulling and can integrate biological proximity detection and pressure detection functions in order to solve the above technical problems.

[0006] A weaving method for a three-dimensional curved surface capacitive sensor comprises the following steps:

[0007] Modeling the shape of the three-dimensional curved surface capacitive sensor as a three-dimensional curved surface mesh;

[0008] converting the three-dimensional surface mesh into weaving information readable by a weaving device;

[0009] Generate a control command using the weaving information, and weave the three-dimensional curved surface capacitive sensor using conductive warp threads and conductive weft threads as fabric; the conductive warp threads and the conductive weft threads each include a bendable core and an insulating layer wrapping the core, and the insulating layer is a deformable elastic material; and

[0010] One or more of the conductive warp threads are connected in parallel to form a driving channel, and one or more of the conductive weft threads are connected in parallel to form a sensing channel; a capacitor node is formed at the intersection and overlap of the driving channel and the sensing channel; the capacitor node is used to form a parasitic capacitor with the organism to detect the approach of the organism; and the capacitor node is used to detect the pressure value when the pressure causes the insulating layer to deform.

[0011] In one embodiment, the step of converting the three-dimensional surface mesh into weaving information readable by a weaving device comprises:

[0012] Setting a weaving starting point on the three-dimensional curved surface grid;

[0013] generating a scalar field according to the geodesic distances of all positions on the three-dimensional surface grid relative to the weaving starting point;

[0014] Extracting contour lines on the scalar field according to a preset interval amount; and

[0015] The three-dimensional curved surface mesh is reconstructed with the contour lines as positions for inserting the conductive warp lines, to generate a weavable quadrilateral mesh; the warp and weft lines of the weavable quadrilateral mesh are continuous; and the weaving information is the weavable quadrilateral mesh.

[0016] In one of the embodiments, in the step of generating a scalar field based on the geodesic distances of all positions on the three-dimensional surface mesh relative to the weaving starting point, the geodesic distances of all positions on the three-dimensional surface mesh relative to the weaving starting point are obtained according to the Dijkstra algorithm, thereby generating the continuously diffused scalar field.

[0017] In one of the embodiments, the three-dimensional surface mesh is a mesh file constructed by triangular facets.

[0018] In one embodiment, the step of converting the three-dimensional surface mesh into weaving information readable by a weaving device comprises:

[0019] Decomposing the three-dimensional surface mesh into a two-dimensional weaving graph A;

[0020] Double the number of rows in weaving pattern A, then maintain continuity by adding and subtracting grids at the corners to form weaving pattern B;

[0021] Generating a weaving pattern C from the weaving pattern B to indicate the feed rate of the warp threads;

[0022] Generating a weaving diagram D from the weaving diagram B to illustrate the selection of the warp threads to be lifted by the jacquard device;

[0023] Wherein, the weaving information includes the weaving pattern C and the weaving pattern D.

[0024] In one of the embodiments, in the step of generating a weaving pattern C from the weaving pattern B to represent the feed rate of the warp, the weaving pattern B is converted from the bottom to the top with the last row as a reference; the state of each grid in the weaving pattern C is represented by a value W, W=1 represents a filled state, and W<1 represents an empty state; if the corresponding grid in the weaving pattern B is empty, the grid in the weaving pattern C will also be empty, and W is -1; if the grid in the reference row is empty, the fabric will shrink to eliminate the gap caused by adjusting the length of the weft; S represents the length of contraction, S=1-W, and the values ​​of all grids in the same row will be added with S.

[0025] In one embodiment, the control command includes:

[0026] Initial commands for moving components of the weaving device to predetermined positions;

[0027] Roller commands, used to control the roller matrix according to the weaving pattern C;

[0028] Jacquard command, controls the jacquard device according to the weaving pattern D;

[0029] a weaving instruction for controlling the weaving device to bring the conductive weft thread into a shed formed by the jacquard device and weave the conductive weft thread onto the conductive warp thread; and

[0030] The end command is used to control the roller matrix to release the winding thread at a preset length.

[0031] In one of the embodiments, the three-dimensional curved surface grid has uniform grid units; the length of each grid unit is equal to the gap between adjacent longitude lines, and the width of each grid unit is equal to the gap between adjacent latitude lines.

[0032] A three-dimensional curved surface capacitive sensor, the three-dimensional curved surface capacitive sensor is woven according to the weaving method of the three-dimensional curved surface capacitive sensor; the three-dimensional curved surface capacitive sensor comprises the driving channel and the sensing channel; the driving channel comprises one or more of the conductive warp threads connected in parallel; the sensing channel comprises one or more of the conductive weft threads connected in parallel;

[0033] Wherein, the conductive warp and the conductive weft both include the bendable core and the insulating layer wrapping the core, and the insulating layer is a deformable elastic material; the conductive warp and the conductive weft form the three-dimensional curved surface structure by a three-dimensional curved surface weaving method;

[0034] The capacitor node is formed at the intersection and overlap of the driving channel and the sensing channel; the capacitor node is used to form a parasitic capacitor with the biological body to detect the approach of the biological body; and the capacitor node is used to detect the pressure value when the pressure causes the insulation layer to deform.

[0035] In one embodiment, the number of conductive warp threads in each of the drive channels is equal;

[0036] And / or, the number of conductive weft threads in each of the sensing channels is equal.

[0037] In one embodiment, the conductive warp thread is a replaceable structure; and / or the conductive weft thread is a replaceable structure.

[0038] In one embodiment, the insulating layer is made of silicone or polytetrafluoroethylene.

[0039] In one of the embodiments, an integrated chip is further included, and the driving channel and the sensing channel are respectively connected to the integrated chip for communication.

[0040] The above-mentioned three-dimensional curved surface capacitive sensor and its weaving method, the conductive warp and the conductive weft are formed into a three-dimensional curved surface structure through the three-dimensional curved surface weaving method, and the structure is simple and tough. The capacitive sensor is not easily damaged during twisting or pulling, is suitable for scenes that need to cover a large area, and is suitable for use in flexible wearable devices. The three-dimensional curved surface capacitive sensor can accurately cover the target to be detected, and the sensing signal can be distributed in an array, making the detection accurate. The above-mentioned weaving method enables the capacitive sensor to accurately fit the curved surface of the target and realize the accurate mapping of the sensing signal in three-dimensional space. Through the control commands generated in the above-mentioned weaving method, reasonable weaving path planning is realized, so that the distribution of the conductive weft can not only meet the continuity of the weaving, but also ensure that each sensing unit is evenly distributed. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, drawings of other embodiments can be obtained based on these drawings without paying creative work.

[0042] Figure 1 is a schematic diagram of a three-dimensional curved surface capacitive sensor in one embodiment;

[0043] Figure 2 for Figure 1 A cross-sectional view of the conductive warp and weft of the three-dimensional curved capacitive sensor shown;

[0044] Figure 3 is a schematic diagram of a flexible wearable device in one embodiment;

[0045] Figure 4A flow chart of a weaving method of a three-dimensional curved surface capacitive sensor in one embodiment;

[0046] Figure 5 for Figure 4 A schematic diagram of a three-dimensional curved surface mesh in an embodiment of the weaving method shown;

[0047] Figure 6 for Figure 4 The flowchart of step S340 in the weaving method in one embodiment is shown;

[0048] Figure 7 for Figure 4 Schematic diagram of a target three-dimensional object in an embodiment of the weaving method shown:

[0049] Figure 8 for Figure 7 A schematic diagram of weaving pattern A in the weaving method shown; Fig. 9 for Figure 7 A schematic diagram of weaving pattern B in the weaving method shown;

[0050] Fig.10 for Figure 7 A schematic diagram of weaving pattern C in the weaving method shown;

[0051] Fig.11 for Figure 7 A schematic diagram of weaving pattern D in the weaving method shown;

[0052] Fig.12 for Figure 4 The flowchart of step S340 in the weaving method in another embodiment is shown;

[0053] Fig.13 for Fig.12 A schematic diagram of a scalar field of a three-dimensional curved surface mesh in one embodiment of the weaving method shown;

[0054] Fig.14 for Fig.13 Schematic diagram of a quadrilateral mesh that can be woven in the weaving method shown;

[0055] Fig.15 for Fig.14 Actual picture of the three-dimensional curved surface capacitive sensor woven by the weaving method shown. DETAILED DESCRIPTION

[0056] For ease of understanding of the present invention, a more comprehensive description of the three-dimensional curved surface capacitive sensor and its weaving method will be provided below with reference to the relevant accompanying drawings. The preferred embodiments of the three-dimensional curved surface capacitive sensor and its weaving method are provided in the accompanying drawings. However, the three-dimensional curved surface capacitive sensor and its weaving method can be implemented in many different forms and are not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the three-dimensional curved surface capacitive sensor and its weaving method more thorough and comprehensive.

[0057] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the three-dimensional curved surface capacitive sensor and the weaving method thereof are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0058] like Figure 1 As shown, a three-dimensional curved surface capacitive sensor 100 in one embodiment includes a driving channel 120 and a sensing channel 140 . The driving channel 120 includes one or more parallel conductive warp threads 122 , and the sensing channel 140 includes one or more parallel conductive weft threads 142 .

[0059] See also Figure 2 , the conductive warp 122 and the conductive weft 142 both include a bendable core 162 and an insulating layer 164 wrapping the core 162, and the insulating layer 164 is a deformable elastic material; the conductive warp 122 and the conductive weft 142 form a three-dimensional curved surface structure by a three-dimensional curved surface weaving method; the driving channel 120 and the sensing channel 140 cross and overlap to form a capacitor node 180; the capacitor node 180 is used to form a parasitic capacitor with the organism to detect the approach of the organism; and the capacitor node 180 is used to detect the pressure value when the pressure causes the insulating layer 164 to deform. By comparing the calibrated static capacitance value with the real-time capacitance value, it can be obtained whether there is a biological approach or an external force. The capacitive sensor 100 with a three-dimensional curved surface structure can accurately cover the target to be detected, and the sensing signal can be distributed in an array, so that the detection is accurate.

[0060] Specifically, each sensing channel 140 and the driving channel 120 are insulated from each other and form a capacitive effect because the woven structure is interlaced with each other, that is, the driving channel 120 serves as the positive electrode of the electrode plate, and the sensing channel 140 serves as the negative electrode of the electrode plate, forming a capacitor node 180. The capacitor node 180 can form a parasitic capacitor with the organism to detect the approach of the organism; when a biological body, such as a human hand, approaches, a parasitic capacitor is generated between the organism and the conductive weft 142, and the capacitor will shunt the charge of the capacitor node 180, thereby reducing the capacitance value detected by the chip. The capacitor node 180 is also used to detect the pressure value when the pressure causes the insulating layer 164 to deform. When an external force acts on the surface of the capacitive sensor 100, the insulating layer 164 wrapped around the conductive warp 122 and the conductive weft 142 is elastic and deforms when pressed, and the distance between the plates of the capacitor node 180 is reduced, resulting in an increase in the capacitance value, thereby detecting the magnitude of the pressure.

[0061] The conductive warp 122 and the conductive weft 142 form a woven structure with a simple structure and strong toughness. The capacitive sensor 100 is not easily damaged during twisting or pulling, and is suitable for scenes that need to cover a large area, and is used in a flexible wearable device 10. The woven structure can be processed and manufactured based on a traditional weaving processing method. In the traditional weaving manufacturing process, a woven product is obtained by interlacing a driving channel 120 and a sensing channel 140 in different directions. In one embodiment, the conductive warp 122 and the conductive weft 142 can be perpendicular to each other, which is easy and convenient to manufacture, and has a stable structure. In other embodiments, the conductive warp 122 and the conductive weft 142 may not be perpendicular to each other to achieve the purpose of weaving a three-dimensional structure.

[0062] In one embodiment, both the conductive warp threads 122 and the conductive weft threads 142 may be replaceable structures. Since the conductive warp threads 122 and the conductive weft threads 142 are connected by weaving, no other fixed connection structure is required, and thus they can be replaced. If part of the conductive warp threads 122 or the conductive weft threads 142 is damaged, only the damaged structure needs to be replaced, and the entire structure does not need to be replaced, which can save costs during maintenance.

[0063] The material of the insulating layer 164 is a deformable elastic material. In the present specific embodiment, the material of the insulating layer 164 is silicone. The silicone shell can make the conductive warp 122 and the conductive weft 142 become thin and soft wires, thereby serving as a weaving material. In another embodiment, the material of the insulating layer 164 can be made of other insulating layer materials such as polytetrafluoroethylene, and the polytetrafluoroethylene material can be a polytetrafluoroethylene material with the trademark Teflon. Different materials exhibit different elastic properties. The harder the material, the lower the force detection sensitivity, but the larger the range. In other embodiments, the material of the insulating layer 164 can also be a rubber or thermoplastic elastomer that can achieve similar hardness, resilience and insulation.

[0064] See also Figure 3 In one embodiment, the number of the conductive warp threads 122 of each of the driving channels 120 may be equal, and the number of the conductive weft threads 142 of each of the sensing channels 140 may also be equal. The conductive warp threads 122 are evenly divided into a plurality of channels, and the number of the conductive warp threads 122 of each sensing channel 140 is the same. Then, when weaving the conductive weft threads 142, a driving channel 120 is formed after weaving a few of them. The length and width of each channel are determined by the number of the conductive warp threads 122 or the conductive weft threads 142 of the channel, thereby forming a vertically intersecting sensing grid. The number of the conductive warp threads 122 and / or the conductive weft threads 142 remains the same to ensure that the sensor density is uniform everywhere, but for special needs, such as some areas that require high-density sensing, fewer conductive warp threads 122 and / or conductive weft threads 142 can be used, so that there are more driving channels 120 and / or sensing channels 140, and higher resolution data is obtained. In other embodiments, the number of the conductive warp threads 122 of each of the driving channels 120 may be unequal, and the number of the conductive weft threads 142 of each of the sensing channels 140 may also be unequal.

[0065] In general, the number of the conductive warp threads 122 of each of the driving channels 120 and the number of the conductive weft threads 142 of each of the sensing channels 140 are both multiple. Figure 1 In the illustrated embodiment, the number is 3. In other embodiments, the number may be 2-6. In one embodiment, the number may be one, in which case the size limit of the detection density lies in the size of a single conductive warp thread 122 and / or conductive weft thread 142.

[0066] For details, see Figure 1 In one embodiment, two adjacent conductive warp threads 122 are respectively located on both sides of the same conductive weft thread 142, and two adjacent conductive weft threads 142 are respectively located on both sides of the same conductive warp thread 122, thereby forming a regular and uniform grid pattern. The structures of each intersection are consistent, making the measurement more accurate. In one embodiment, the conductive warp threads 122 and the conductive weft threads 142 are woven into one body in a plain weave manner. The plain weave conductive warp threads 122 and the conductive weft threads 142 have the most interlacing points and the yarns are more bent, so the fabric surface is flat, the body is straight, the texture is firm, the appearance is tight, and the structural strength is good. In other embodiments, the organizational form of the conductive warp threads 122 and the conductive weft threads 142 can also be a twill weave or a satin weave.

[0067] In one embodiment, the capacitive sensor 100 may further include an integrated chip, and the driving channel 120 and the sensing channel 140 are respectively connected to the integrated chip for communication. The integrated chip scans each capacitor node 180 and calculates the capacitance value. In other embodiments, the capacitive sensor 100 may also be combined with an external chip to achieve the purpose of scanning the capacitor node 180.

[0068] See also Figure 3 The embodiment of the present application further provides a flexible wearable device 10, which includes a device body 200 and the capacitive sensor 100 in the above embodiment, wherein the capacitive sensor 100 is disposed on the device body 200 and is communicatively connected with the device body 200. The flexible wearable device 10 can be a hairband, a wristband, a vest or other wearable device.

[0069] The design of the woven structure makes the capacitive sensor 100 flexible and wearable, and can adapt to different body parts and movements. The three-dimensional curved capacitive sensor 100 can accurately cover the target to be detected. The capacitive sensor 100 detects the approach of the organism by measuring the change in capacitance value and converts it into proximity distance data. The sensing signal can be distributed in an array, making the detection accurate. At the same time, the characteristics of the woven structure also enable the sensor to sensitively sense the force on the sensor surface and quantify the magnitude of the force. The capacitive sensor 100 can be integrated with existing electronic equipment and systems to achieve real-time monitoring and data transmission, so that it has broad application prospects in the fields of biomedicine, motion analysis, human-computer interaction, etc. The sensor in the above embodiment can also be covered on the surface of industrial machinery, such as an industrial robot arm, so that the machinery has an additional dimension of perception function and realizes human-computer interaction under intelligent industry.

[0070] See also Figure 4 The embodiment of the present application also provides a weaving method of a three-dimensional curved surface capacitive sensor 100, and the weaving method comprises the following steps:

[0071] S320 , modeling the shape of the three-dimensional curved surface capacitive sensor 100 as a three-dimensional curved surface mesh.

[0072] S340, converting the three-dimensional surface mesh into weaving information readable by a weaving device.

[0073] S360 , generating a control command based on the weaving information, and using the conductive warp threads 122 and the conductive weft threads 142 as the fabric to weave the three-dimensional curved surface capacitive sensor 100 .

[0074] The conductive warp threads 122 and the conductive weft threads 142 each include a bendable core thread 162 and an insulating layer 164 wrapping the core thread 162 . The insulating layer 164 is a deformable elastic material.

[0075] In one embodiment, the control commands may include an initial command, a roller command, a jacquard command, a weaving instruction, and an end command. The initial command is used to move a component of the weaving device to a predetermined position. The roller command is used to control the roller matrix according to the weaving pattern C. The jacquard command controls the jacquard device according to the weaving pattern D. The weaving instruction is used to control the weaving device to bring the conductive weft thread 142 into the shed formed by the jacquard device and weave the conductive weft thread 142 on the conductive warp thread 122. The end command is used to control the roller matrix to release the winding thread at a preset length. The control commands include the commands required by the work line during the weaving process.

[0076] S380 , one or more conductive warp threads 122 are connected in parallel to form a driving channel 120 , and one or more conductive weft threads 142 are connected in parallel to form a sensing channel 140 .

[0077] The intersection and overlap of the driving channel 120 and the sensing channel 140 forms a capacitor node 180. The capacitor node 180 is used to form a parasitic capacitor with the biological body to detect the proximity of the biological body. The capacitor node 180 is also used to detect the pressure value when the pressure causes the insulating layer 164 to deform.

[0078] Step S320 provides a mesh processing strategy to reconstruct the desired three-dimensional shape into a three-dimensional surface mesh. The desired three-dimensional shape is the input of the method, and the three-dimensional surface mesh is an available mesh type for subsequent steps. In one embodiment, each unit of the three-dimensional surface mesh has the same size. Step S340 provides a method for extracting a weaving pattern. To meet the requirements of the weaving device, this step converts the weaving information into a row-to-row continuous weaving pattern that is readable by the weaving device. After having the weaving pattern, in step S360, the final control command can be generated to control the weaving device to perform corresponding operations.

[0079] In one embodiment, see Figure 5 The three-dimensional curved surface grid can have uniform grid units. The length of each grid unit is equal to the gap between adjacent conductive warp lines 122, and the width of each grid unit is equal to the gap between adjacent conductive weft lines 142. The shape of the unit can be a rectangle, a triangle, or a parallelogram. Triangular units are allowed in the convergence region.

[0080] For details, see Figure 6 In one embodiment, step S340 may include the following steps:

[0081] S342, decomposing the three-dimensional surface mesh into a two-dimensional weaving graph A.

[0082] S344, doubling the number of rows of weaving pattern A, and then forming weaving pattern B by adding and subtracting grids at the corners to maintain continuity.

[0083] S346 , generating a weaving pattern C from the weaving pattern B to indicate the feed rate of the conductive warp threads 122 .

[0084] S348, generating weaving pattern D from weaving pattern B to illustrate that the jacquard device selects the conductive warp thread 122 to be lifted.

[0085] The weaving information includes a weaving pattern C and a weaving pattern D. The order of steps S346 and S348 may be changed.

[0086] In one embodiment, step S340 is performed Figure 7 The target 3D object shown is reconstructed into a 3D surface mesh. Figure 8-11 It is shown that the four weaving diagrams generated during the whole conversion process describe different states, namely, weaving diagrams AD.

[0087] refer to Figure 8 In step S342, the three-dimensional surface mesh is decomposed into a two-dimensional weaving graph A. Valid line segments are marked in gray, and invalid meshes are marked with a cross. The mountain-shaped three-dimensional surface of the three-dimensional surface mesh can be expanded into a plane by cutting the side of the surface. Depending on the size of the weaving unit, the plane can be converted into a grid, which is called weaving graph A.

[0088] refer to Fig. 9 , in step S344, by considering the continuity in the weaving process, the weaving pattern of each row is continuously divided into two rows to obtain the weaving pattern B. In order to maintain the row continuity of the entire weaving pattern, the number of rows in the weaving pattern A is first doubled, and then the grids are increased or decreased at the corners to form a new weaving pattern B.

[0089] refer to Fig.10 In one embodiment, in step S346, weaving diagram B is converted from bottom to top with the last row as a reference. The state of each grid in weaving diagram C is represented by a value W, W=1 represents a filled state, and W<1 represents an empty state. If the corresponding grid in weaving diagram B is empty, the grid in weaving diagram C will also be empty, and W is -1. If the grid in the reference row is empty, the fabric will shrink to eliminate the gaps created by adjusting the length of the conductive weft thread 142, which is done after adjusting the length of the conductive warp thread 122. S represents the length of the shrinkage, S=1-W, and S is added to the values ​​of all grids in the same row. Weaving diagram C is generated from weaving diagram B to represent the feed rate of the conductive warp thread 122. Gray stitches are valid (+1), while other stitches are invalid, and the corresponding values ​​are negative.

[0090] refer to Fig.11, a weaving diagram D can be generated by adding a column to the right side of the weaving diagram B and invalidating the adjacent stitches. The purpose of generating the weaving diagram D is to ensure that the jacquard machine of the weaving device can correctly select the jacquard thread. One column corresponds to two adjacent conductive warps 122. For a valid grid, one of the two adjacent conductive warps 122 is raised to form a shed, while the two adjacent conductive warps 122 of an invalid grid should be lowered. Therefore, there is another column in the weaving diagram D, and each column corresponds to a conductive warp 122. For the valid grid, one adjacent conductive warp 122 is raised, while for the invalid grid, when the weaving diagram B is converted to the weaving diagram D, both adjacent conductive warps 122 are lowered. The above weaving method enables the capacitive sensor 100 to accurately fit the curved surface of the target and realize the accurate mapping of the sensing signal in three-dimensional space. Through the control command generated in the above weaving method, reasonable shuttle weaving path planning is realized, so that the distribution of the conductive weft 142 can not only meet the continuity of shuttle weaving, but also ensure that each sensing unit is evenly distributed.

[0091] See also Fig.12 In another embodiment, in the weaving method of the three-dimensional curved surface capacitive sensor, the three-dimensional free-form surface is reduced in dimension to obtain a two-dimensional weaving path. This technology is further optimized in this embodiment to obtain a weaving path that can satisfy the weaving continuity and ensure that each sensor unit is evenly distributed, thereby ensuring that a flexible sensor array that can cover the three-dimensional free-form surface can be woven. Specifically, in this embodiment, step S340 includes the following steps:

[0092] S352, setting a weaving starting point on the three-dimensional surface mesh. A mesh with a boundary generally has a portion of edges. In one embodiment, this portion of the edges can be used as the starting point. Fig.13 In one embodiment, the weaving start point is at the bottom edge of the columnar body in the figure. The shape of the modeled three-dimensional curved surface capacitive sensor can be as follows: Fig.13 The surface of the cylinder with a thin middle and two ends shown can also be any surface with boundaries.

[0093] S354, generating a scalar field according to the geodesic distances of all positions on the three-dimensional surface grid relative to the weaving starting point. The schematic diagram of the scalar field can be found in Fig.13 The scalar field is a geodesic distance field that marks the shortest path from each point on the surface to the starting point. In one embodiment, the geodesic distances of all positions on the three-dimensional surface grid relative to the weaving starting point can be obtained according to the Dijkstra algorithm, thereby generating a continuously diffused scalar field.

[0094] S356, extracting contour lines on the scalar field according to a preset interval. After homogenization, the grid can be divided into several parts and contour lines can be extracted by determining the interval. For example, if 0.1 is used as the interval, 10 parts can be obtained and 11 contour lines can be extracted.

[0095] S358, using the contour lines as the positions for inserting the conductive warp lines, reconstructing the three-dimensional curved surface mesh, and generating a weavable quadrilateral mesh. The weft and warp lines of the weavable quadrilateral mesh are continuous. The above weaving information is the weavable quadrilateral mesh in this embodiment.

[0096] The weft-woven quadrilateral grid is weavable, specifically referring to the weft yarns being woven from one place (e.g. Fig.14 Take the lower left corner of the picture as the starting point and continuously weave it towards the other end to complete the entire grid with one line, referring to the principle of one-stroke drawing.

[0097] In one embodiment, the fabric of the three-dimensional curved surface capacitive sensor may also include common yarns. The contour lines may be used as locations for inserting conductive warps, and the distribution of common wefts between each contour line may be planned, thereby achieving uniform distribution of conductive channels. Fig.14 In this embodiment, the contour lines are horizontal lines, and the quadrilateral grid can be woven into a fine grid in the figure.

[0098] In one embodiment, the three-dimensional surface mesh can be a mesh file constructed by triangular facets, which is a triangular mesh. This topological structure can provide information on vertices, edges, and faces. The points on the mesh are carriers of geodesic field values, and each point has a set of values. Since the geodesic field records the shortest path, the mesh can be divided into strips of uniform width by segmenting the geodesic field.

[0099] The weavable quadrilateral mesh is a quadrilateral. After extracting the geodetic field from the triangular mesh, the triangular mesh is reconstructed and converted into a quadrilateral mesh. The advantage of this mesh is that it can correspond to the weaving unit one by one (each quadrilateral is the intersection of two warps and wefts), and the weaving path of the weft can be obtained. Therefore, the weaving information can be the weavable quadrilateral mesh generated in step S358.

[0100] Fig.15A physical picture of a three-dimensional curved surface capacitive sensor woven by the weaving method described in the above embodiment. By improving steps S352-S358, it is ensured that each strip area is continuously weavable, and a weaving path that can satisfy both weaving continuity and uniform distribution of each sensor unit can be obtained, so that a flexible sensor array that can cover a three-dimensional free-form surface can be woven. The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0101] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A weaving method for a three-dimensional curved surface capacitive sensor, It is characterized in that The steps include: Modeling the shape of the three-dimensional curved surface capacitive sensor as a three-dimensional curved surface mesh; converting the three-dimensional surface mesh into weaving information readable by a weaving device; The control command is generated by the weaving information, and the three-dimensional curved surface capacitive sensor is woven with conductive warp and conductive weft as fabric; the conductive warp and the conductive weft each include a bendable core and an insulating layer wrapping the core, and the insulating layer is a deformable elastic material; as well as One or more of the conductive warp threads are connected in parallel to form a driving channel, and one or more of the conductive weft threads are connected in parallel to form a sensing channel; A capacitance node is formed at the intersection and overlap of the driving channel and the sensing channel; the capacitance node is used to form a parasitic capacitance with the biological body to detect the approach of the biological body; and the capacitance node is used to detect the pressure value when the pressure causes the insulation layer to deform.

2. The weaving method of the three-dimensional curved surface capacitive sensor according to claim 1, It is characterized in that The step of converting the three-dimensional curved surface mesh into weaving information readable by the weaving device comprises: Setting a weaving starting point on the three-dimensional curved surface grid; generating a scalar field according to the geodesic distances of all positions on the three-dimensional surface grid relative to the weaving starting point; Extracting contour lines on the scalar field according to a preset interval amount; and The three-dimensional curved surface mesh is reconstructed with the contour lines as positions for inserting the conductive warp lines, to generate a weavable quadrilateral mesh; the warp and weft lines of the weavable quadrilateral mesh are continuous; and the weaving information is the weavable quadrilateral mesh.

3. The weaving method of the three-dimensional curved surface capacitive sensor according to claim 2, It is characterized in that In the step of generating a scalar field according to the geodesic distances of all positions on the three-dimensional surface mesh relative to the weaving starting point, the geodesic distances of all positions on the three-dimensional surface mesh relative to the weaving starting point are obtained according to the Dijkstra algorithm, thereby generating the continuously diffused scalar field.

4. The weaving method of the three-dimensional curved surface capacitive sensor according to claim 2, It is characterized in that The three-dimensional surface mesh is a mesh file constructed by triangular facets.

5. The weaving method of the three-dimensional curved surface capacitive sensor according to claim 1, It is characterized in that The step of converting the three-dimensional curved surface mesh into weaving information readable by the weaving device comprises: Decomposing the three-dimensional surface mesh into a two-dimensional weaving graph A; Double the number of rows in weaving pattern A, then maintain continuity by adding and subtracting grids at the corners to form weaving pattern B; Generating a weaving pattern C from the weaving pattern B to indicate the feed rate of the warp threads; Generating a weaving diagram D from the weaving diagram B to illustrate the selection of the warp threads to be lifted by the jacquard device; Wherein, the weaving information includes the weaving pattern C and the weaving pattern D.

6. The weaving method of the three-dimensional curved surface capacitive sensor according to claim 5, It is characterized in that In the step of generating a weaving pattern C from the weaving pattern B to represent the feed rate of the warp, the weaving pattern B is converted from the bottom to the top with the last row as a reference; the state of each grid in the weaving pattern C is represented by a value W, W=1 represents a filled state, and W<1 represents an empty state; if the corresponding grid in the weaving pattern B is empty, the grid in the weaving pattern C will also be empty, and W is -1; if the grid in the reference row is empty, the fabric will shrink to eliminate the gap generated after adjusting the length of the weft; S represents the length of the shrinkage, S=1-W, and the values ​​of all grids in the same row will be added with S.

7. The weaving method of the three-dimensional curved surface capacitive sensor according to claim 1, It is characterized in that The three-dimensional curved surface grid has uniform grid units; the length of each grid unit is equal to the gap between adjacent longitude lines, and the width of each grid unit is equal to the gap between adjacent latitude lines.

8. A three-dimensional curved surface capacitive sensor, the three-dimensional curved surface capacitive sensor being woven according to the weaving method of a three-dimensional curved surface capacitive sensor according to any one of claims 1 to 7; It is characterized in that The three-dimensional curved surface capacitive sensor comprises the driving channel and the sensing channel; the driving channel comprises one or more parallel conductive warps; the sensing channel comprises one or more parallel conductive wefts; Wherein, the conductive warp and the conductive weft both include the bendable core and the insulating layer wrapping the core, and the insulating layer is a deformable elastic material; the conductive warp and the conductive weft form the three-dimensional curved surface structure by a three-dimensional curved surface weaving method; The capacitor node is formed at the intersection and overlap of the driving channel and the sensing channel; the capacitor node is used to form a parasitic capacitor with the biological body to detect the approach of the biological body; and the capacitor node is used to detect the pressure value when the pressure causes the insulation layer to deform.

9. The three-dimensional curved surface capacitive sensor according to claim 8, It is characterized in that The conductive warp thread is a replaceable structure; and / or the conductive weft thread is a replaceable structure.

10. The three-dimensional curved surface capacitive sensor according to claim 8, It is characterized in that The material of the insulating layer is silicone or polytetrafluoroethylene.

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