Low-crosstalk array type flexible sensor based on 3D printing

Abstract

The utility model provides a low-crosstalk array type flexible sensor based on 3D printing. The low-crosstalk array type flexible sensor comprises an upper insulating layer, a piezoelectric sensing element layer and a lower insulating layer which are sequentially arranged from top to bottom, each piezoelectric sensing element layer comprises a plurality of piezoelectric assemblies which are distributed in an array mode, and each piezoelectric assembly comprises an upper electrode plate, a piezoelectric material layer and a lower electrode plate which are sequentially arranged from top to bottom; in each row or column of piezoelectric assemblies, adjacent upper electrode plates are electrically connected with each other, and in each row or column of upper electrode plates which are electrically connected, the first or last upper electrode plate is electrically connected with an external circuit through a first electrode wire; in each row or column of piezoelectric assemblies, adjacent lower electrode plates are electrically connected with each other, and in each row or column of lower electrode plates forming electrical connection, the first or last lower electrode plate is electrically connected with an external circuit through a second electrode wire. The flexible sensor is simple in structure, the precision and sensitivity of the flexible sensor can be effectively improved, and crosstalk is not easy to form.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, and more specifically, to a low-crosstalk array flexible sensor based on 3D printing. Background Art

[0002] Flexible piezoelectric sensors have broad application prospects in the fields of wearable sensing devices, soft robots, and large-deformation structure shape monitoring.

[0003] However, in the prior art, flexible array sensors still face two major problems. One is the crosstalk problem between array units. How to isolate the crosstalk between components while ensuring a large resolution of the sensor is the key to improving the sensing accuracy of the sensor. The other is the manufacturing process problem. Traditional machining is difficult to apply to elastic polymer materials, and the MEMS process makes the manufacturing cost expensive. The 3D printing process has become the preferred manufacturing process due to its advantages in forming complex structures and low cost. Therefore, how to realize the 3D printing manufacturing of composite material flexible sensors has become the key to its wide application.

[0004] Currently, there are precedents of pressure sensors made based on 3D printing technology. For example, a patent with the publication number CN111649665A discloses a spider-web-like flexible strain sensor capable of identifying strain directions and a preparation method thereof. The material layers are stacked layer by layer through 3D printing technology to obtain the required sensor. However, such a sensor with a layered structure is extremely prone to cracking and peeling when subjected to large deformations. Summary of the Utility Model

[0005] The technical problem to be solved by the utility model is to provide a low-crosstalk array flexible sensor based on 3D printing, which has a simple structure and reduces the crosstalk between adjacent units while increasing the sensor array density.

[0006] The utility model provides a low-crosstalk array flexible sensor based on 3D printing, which includes an upper insulating layer, a piezoelectric sensing element layer, and a lower insulating layer arranged in sequence from top to bottom; the piezoelectric sensing element layer includes a plurality of piezoelectric components arranged in an array, and each piezoelectric component includes an upper electrode sheet, a piezoelectric material layer, and a lower electrode sheet arranged in sequence from top to bottom; in each row or column of piezoelectric components, adjacent upper electrode sheets are electrically connected to each other, and in each row or column of upper electrode sheets forming an electrical connection, the first or last upper electrode sheet is electrically connected to an external circuit through a first electrode wire; in each row or column of piezoelectric components, adjacent lower electrode sheets are electrically connected to each other, and in each row or column of lower electrode sheets forming an electrical connection, the first or last lower electrode sheet is electrically connected to an external circuit through a second electrode wire; the first electrode wire and the second electrode wire correspond one by one.

[0007] Compared with the prior art, the present application has the following advantages: The piezoelectric components are arranged in an array, making the piezoelectric sensing element layer relatively uniform, and when being squeezed, the force is more evenly distributed, facilitating external force application at any position. Additionally, due to the equal number of elements in each row and / or each column in the matrix structure, it is convenient for adjacent upper electrode plates or adjacent lower electrode plates in each row to be electrically connected to each other, or for adjacent upper electrode plates or adjacent lower electrode plates in each column to be electrically connected to each other. The arrangement is orderly, enabling wiring in the form of rows or columns, which can effectively reduce the number of wirings, avoid crosstalk problems between adjacent piezoelectric components, facilitate large-area distribution, and thus improve the accuracy and sensitivity of the sensor itself. The first electrode lines and the second electrode lines correspond one by one to ensure that a loop is formed between each first electrode line and the corresponding second electrode line through positive and negative currents, guaranteeing the normal use of the sensor.

[0008] In a possible implementation manner, grooves are provided on the lower surface of the upper electrode plate and the upper surface of the lower electrode plate, and protrusions for being placed in the grooves to form a limit are provided on the upper and lower surfaces of the piezoelectric material layer.

[0009] Compared with the prior art, adopting the above technical solution can easily form a tight fit between the piezoelectric material layer, the upper electrode plate, and the lower electrode plate, making the fit closer, thereby increasing the accuracy and sensitivity when subjected to external pressure, and avoiding the defect that the layers are prone to peeling under the action of large stress.

[0010] In a possible implementation manner, a circular flange for being padded between the upper electrode plate and the lower electrode plate is provided on the circumference of the piezoelectric material layer.

[0011] Compared with the prior art, adopting the above technical solution can prevent the upper electrode plate and the lower electrode plate from directly contacting each other to form a short circuit.

[0012] In a possible implementation manner, among the upper electrode plates in each row or each column, adjacent upper electrode plates are electrically connected through leads in an S-shaped structure; among the lower electrode plates in each row or each column, adjacent lower electrode plates are electrically connected through leads in an S-shaped structure.

[0013] Compared with the prior art, adopting the above technical solution can endow the sensor with good tensile properties, not easily break under tension, and can reduce crosstalk between adjacent pixels.

[0014] In a possible implementation manner, among the upper electrode plates in each row, adjacent upper electrode plates are electrically connected to each other; among the lower electrode plates in each column, adjacent lower electrode plates are electrically connected.

[0015] Compared with the prior art, adopting the above technical solution can make the first electrode line of the upper electrode sheet arranged horizontally and the second electrode line of the lower electrode sheet arranged vertically, so that the first electrode line and the second electrode line can be alternately staggered, the wiring is orderly, and crosstalk is avoided.

[0016] In a possible implementation manner, both the upper insulating layer and the lower insulating layer are made of PI film.

[0017] Compared with the prior art, adopting the above technical solution can effectively insulate, has good heat resistance, strong mechanical properties, good dielectric properties, and also has good flexibility, which is convenient for the use of flexible sensors.

[0018] In a possible implementation manner, the piezoelectric material layer is made by 3D printing.

[0019] Compared with the prior art, adopting the above technical solution is convenient for preparation and simple in production.

[0020] In a possible implementation manner, each piezoelectric component has a cylindrical structure.

[0021] Compared with the prior art, adopting the above technical solution can facilitate large-area arrangement and is convenient for force application in the up and down directions. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic diagram of the overall disassembly of the present utility model;

[0023] Figure 2 is a partial schematic diagram of the matrix distribution of the piezoelectric components of the present utility model;

[0024] Figure 3 is a detailed schematic diagram of the piezoelectric component of the present utility model;

[0025] Figure 4 is a schematic diagram of the electrical connection relationship of the matrix distribution of the upper electrode sheet in the present utility model;

[0026] Figure 5 is a schematic diagram of the electrical connection relationship of the matrix distribution of the lower electrode sheet in the present utility model;

[0027] DESCRIPTION OF THE REFERENCE NUMERALS:

[0028] 1 - upper insulating layer, 2 - piezoelectric sensing element layer, 3 - lower insulating layer, 20 - piezoelectric component, 100.1 - lead wire, 101 - first electrode line, 102 - second electrode line, 200 - groove, 201 - upper electrode sheet, 202 - piezoelectric material layer, 202.1 - protrusion, 202.2 - annular flange, 203 - lower electrode sheet. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] First of all, those skilled in the art should understand that these embodiments are only used to explain the technical principles of the embodiments of this application, and are not intended to limit the protection scope of the embodiments of this application. Those skilled in the art can make adjustments according to needs to adapt to specific application scenarios.

[0030] In the description of the embodiments of this application, it should be noted that unless otherwise clearly specified and limited, the terms "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

[0031] In the embodiments of this application, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature is at a higher horizontal height than the second feature. The first feature being "under", "beneath" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature is at a lower horizontal height than the second feature.

[0032] The following further describes this application in detail with reference to the drawings and specific embodiments.

[0033] See Figure 1 , the embodiments of this application disclose a low-crosstalk array flexible sensor based on 3D printing, including an upper insulating layer 1, a piezoelectric sensing element layer 2, and a lower insulating layer 3 arranged in sequence from top to bottom; see Figure 2 , the piezoelectric sensing element layer 2 all includes a plurality of piezoelectric components 20 arranged in an array, see Figure 3 , each piezoelectric component 20 all includes an upper electrode sheet 201, a piezoelectric material layer 202, and a lower electrode sheet 203 arranged in sequence from top to bottom; see Figure 4 , in each row of piezoelectric components 20, the adjacent upper electrode sheets 201 are electrically connected to each other, and in each row of upper electrode sheets 201 that form an electrical connection, the last upper electrode sheet 201 is electrically connected to an external circuit through a first electrode wire 101; see Figure 5 , in each column of piezoelectric components 20, the adjacent lower electrode sheets 203 are electrically connected to each other, and in each column of lower electrode sheets 203 that form an electrical connection, the last lower electrode sheet 203 is electrically connected to an external circuit through a second electrode wire 102; the first electrode wire 101 and the second electrode wire 102 correspond one by one.

[0034] In this embodiment, the piezoelectric assemblies 20 are arranged in a 10×10 matrix. Those skilled in the art can flexibly adjust the matrix size formed by the piezoelectric assemblies 20 according to actual situations. 7 wt% of three-dimensional polypyrrole can be added to the piezoelectric material layer 202 to increase the electrical conductivity. The upper electrode plate 201 and the lower electrode plate 203 can be made of silver. Moreover, the piezoelectric material layer 202, the upper electrode plate 201, and the lower electrode plate 203 can all be made by 3D printing. The array distribution of the piezoelectric assemblies 20 makes the piezoelectric sensing element layer 2 relatively uniform, and when being squeezed, the force is more uniform, which is convenient for an external force to be applied at any position. In addition, since the number of each row and / or each column in the matrix structure is equal, it is convenient for the adjacent upper electrode plates 201 in each row to be electrically connected to each other, or the adjacent lower electrode plates 203 in each column to be electrically connected to each other. The arrangement is orderly, so that the wiring is carried out in the form of rows or columns, which can effectively reduce the number of wirings, avoid crosstalk problems between adjacent piezoelectric assemblies 20, facilitate large-area distribution, and further improve the accuracy and sensitivity of the sensor itself. The first electrode wires 101 and the second electrode wires 102 are in one-to-one correspondence to ensure that a separate circuit is formed between each first electrode wire 101 and the corresponding second electrode wire 102 through positive and negative currents, ensuring the normal use of the sensor.

[0035] In some embodiments, in each column of piezoelectric assemblies 20, the adjacent upper electrode plates 201 are electrically connected to each other. Among the upper electrode plates 201 in each column that form electrical connections, the first or last upper electrode plate 201 is electrically connected to an external circuit through the first electrode wire 101. In each row of piezoelectric assemblies 20, the adjacent lower electrode plates 203 are electrically connected to each other. Among the lower electrode plates 203 in each row that form electrical connections, the first or last lower electrode plate 203 is electrically connected to an external circuit through the second electrode wire 102. The first electrode wires 101 and the second electrode wires 102 are in one-to-one correspondence.

[0036] In some embodiments, in each column of piezoelectric assemblies 20, the adjacent upper electrode plates 201 are electrically connected to each other. Among the upper electrode plates 201 in each column that form electrical connections, the first or last upper electrode plate 201 is electrically connected to an external circuit through the first electrode wire 101. In each column of piezoelectric assemblies 20, the adjacent lower electrode plates 203 are electrically connected to each other. Among the lower electrode plates 203 in each column that form electrical connections, the first or last lower electrode plate 203 is electrically connected to an external circuit through the second electrode wire 102. The first electrode wires 101 and the second electrode wires 102 are in one-to-one correspondence.

[0037] In some embodiments, in each row of piezoelectric components 20, adjacent upper electrode plates 201 are electrically connected to each other. In each column of upper electrode plates 201 where electrical connection is formed, the first or the last upper electrode plate 201 is electrically connected to an external circuit through a first electrode wire 101. In each row of piezoelectric components 20, adjacent lower electrode plates 203 are electrically connected to each other. In each row of lower electrode plates 203 where electrical connection is formed, the first or the last lower electrode plate 203 is electrically connected to an external circuit through a second electrode wire 102. The first electrode wire 101 and the second electrode wire 102 are in one-to-one correspondence.

[0038] See Figure 3 , in some embodiments, grooves 200 are formed on the lower surface of the upper electrode plate 201 and the upper surface of the lower electrode plate 203. Protrusions 202.1 for being placed in the grooves 200 to form a limit are provided on the upper and lower surfaces of the piezoelectric material layer 202.

[0039] In this embodiment, it is easy to form a tight fit between the piezoelectric material layer 202 and the upper electrode plate 201 and the lower electrode plate 203, the fitting is closer, and the defect that the layers are likely to fall off under the action of large stress is avoided.

[0040] See Figure 2 , in some embodiments, a circular flange 202.2 for being padded between the upper electrode plate 201 and the lower electrode plate 203 is provided on the circumference of the piezoelectric material layer 202.

[0041] In this embodiment, the circular flange 202.2 can prevent the upper electrode plate 201 and the lower electrode plate 203 from being directly attached together to form a short circuit.

[0042] See Figure 3 , in some embodiments, in each row or each column of upper electrode plates 201, adjacent upper electrode plates 201 are electrically connected through a lead 100.1 with an S-shaped structure; in each row or each column of lower electrode plates 203, adjacent lower electrode plates 203 are electrically connected through a lead 100.1 with an S-shaped structure.

[0043] See Figure 4 and Figure 5 , this embodiment can provide sufficient gaps between adjacent upper electrode plates 201 and between adjacent lower electrode plates 203, and the leads are not easily broken when being squeezed.

[0044] In some embodiments, in each row of upper electrode plates 201, adjacent upper electrode plates 201 are electrically connected to each other; in each column of lower electrode plates 203, adjacent lower electrode plates 203 are electrically connected.

[0045] See Figure 4 and Figure 5, in this embodiment, each first electrode wire 101 in the upper electrode sheet 201 can be arranged horizontally, and each second electrode wire 102 in the lower electrode sheet 203 can be arranged vertically. After assembly, the first electrode wire 101 and the second electrode wire 102 can be alternately staggered with orderly wiring, avoiding crosstalk. It is easy to think that it can also be the other way around, that is, in each column of upper electrode sheets 201, adjacent upper electrode sheets 201 are electrically connected to each other; in each row of lower electrode sheets 203, adjacent lower electrode sheets 203 are electrically connected.

[0046] In some embodiments, both the upper insulating layer 1 and the lower insulating layer 3 are made of PI film. The PI film can effectively insulate and has good flexibility, playing a role in protecting the flexible sensor.

[0047] In some embodiments, the piezoelectric material layer 202 is made by 3D printing with PVDF solution. The PVDF solution has good corrosion resistance, chemical resistance, high temperature resistance, and high mechanical strength.

[0048] In some embodiments, each piezoelectric component 20 has a cylindrical structure. This is convenient for the large-area arrangement of the piezoelectric component 20 and convenient for the force in the up and down directions.

[0049] In the description of the embodiments of the present application, it should be noted that in the description of the present application, the terms "inner", "outer", etc. indicating the direction or positional relationship are based on the direction or positional relationship shown in the drawings. This is only for convenience of description and does not indicate or imply that the device or component must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application.

[0050] In the description of the present application, the description referring to terms such as "one embodiment", "some embodiments", "in this embodiment", "specific example", or "some examples" means that the specific features, mechanisms, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, mechanisms, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0051] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A low crosstalk array flexible sensor based on 3D printing, characterized in that: The invention comprises an upper insulating layer (1), a piezoelectric sensor element layer (2) and a lower insulating layer (3) which are arranged in sequence from top to bottom; the piezoelectric sensor element layer (2) comprises a plurality of piezoelectric components (20) which are arranged in an array, and each of the piezoelectric components (20) comprises an upper electrode sheet (201), a piezoelectric material layer (202) and a lower electrode sheet (203) which are arranged in sequence from top to bottom; in each row or column of the piezoelectric components (20), adjacent upper electrode sheets (201) are electrically connected to each other, and in each row or column where the electrical connection is formed, the upper electrode sheets (201) are electrically connected to each other. Among the upper electrode sheets (201), the first or the last upper electrode sheet (201) is electrically connected to an external circuit via a first electrode line (101); in each row or column of the piezoelectric components (20), adjacent lower electrode sheets (203) are electrically connected to each other, and in each row or column of the lower electrode sheets (203) that form an electrical connection, the first or the last lower electrode sheet (203) is electrically connected to an external circuit via a second electrode line (102); the first electrode line (101) corresponds to the second electrode line (102) one by one.

2. The low crosstalk array flexible sensor based on 3D printing according to claim 1, characterized in that: The lower surface of the upper electrode sheet (201) and the upper surface of the lower electrode sheet (203) are both provided with grooves (200), and the upper and lower surfaces of the piezoelectric material layer (202) are both provided with protrusions (202.1) for being placed in the grooves (200) to form a limit.

3. The low crosstalk array flexible sensor based on 3D printing according to claim 2, characterized in that: The piezoelectric material layer (202) is provided with an annular flange (202.2) on the circumference thereof and is used to cushion between the upper electrode sheet (201) and the lower electrode sheet (203).

4. The low crosstalk array flexible sensor based on 3D printing according to claim 1, 2 or 3, characterized in that: In each row or column of the upper electrode sheets (201), adjacent upper electrode sheets (201) are electrically connected via leads (100.1) of an S-shaped structure; and in each row or column of the lower electrode sheets (203), adjacent lower electrode sheets (203) are electrically connected via leads (100.1) of an S-shaped structure.

5. The low crosstalk array flexible sensor based on 3D printing according to claim 4, characterized in that: In each row of the upper electrode sheets (201), adjacent upper electrode sheets (201) are electrically connected to each other; and in each column of the lower electrode sheets (203), adjacent lower electrode sheets (203) are electrically connected to each other.

6. The low crosstalk array flexible sensor based on 3D printing according to claim 1, 2, 3 or 5, characterized in that: The upper insulating layer (1) and the lower insulating layer (3) are both made of pi film.

7. The low crosstalk array flexible sensor based on 3D printing according to claim 1, 2, 3 or 5, characterized in that: The piezoelectric material layers (202) are all made by 3D printing.

8. The low crosstalk array flexible sensor based on 3D printing according to claim 1, 2, 3 or 5, characterized in that: Each of the piezoelectric components (20) has a cylindrical structure.

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