A method for manufacturing a fully fitted sensor array of a non-unfolded surface

Abstract

The present application discloses a method for making a fully fitted sensor array for a non-expanded surface, and relates to the field of direct writing printing technology. The method divides the area where the signal monitoring point is located in the surface model of the three-dimensional surface to be monitored into a number of surface units, and projects each surface unit onto a plane to obtain a corresponding sub-plane, and then prints a sub-sensor array according to the position of the signal monitoring point in each sub-plane using the direct writing printing technology, and fits each printed sub-sensor array to the corresponding surface unit of the three-dimensional surface to be monitored, so that the sensing unit in each sub-sensor array is located at the signal monitoring point of the corresponding surface unit, and each sub-sensor array is connected to form a fully fitted sensor array for the three-dimensional surface to be monitored. The method simply and effectively realizes a fully fitted sensor array for a non-expanded surface, so that large-scale signal monitoring of the non-expanded surface can be realized.

Description

Technical Field

[0001] The present application relates to the field of direct writing printing technology, and in particular to a method for manufacturing a fully fitted sensor array of a non-unfolded curved surface. Background Art

[0002] A sensor is a unit that converts signal changes on an object into electrical signals. A single sensor unit can only measure the signal at a single point. Therefore, in order to achieve real-time monitoring of a large area, an array design is required to form an array sensor.

[0003] Except for a few cases where the surface of the monitored structure is a plane, in more practical application scenarios, the surface of the monitored structure is a curved surface: when the surface of the monitored structure is an ordinary expandable surface, a bonding manufacturing method from a two-dimensional plane to a three-dimensional surface can be used to produce an array sensor that fully bonds to its surface. However, when the surface of the monitored structure is a non-expandable surface, it is extremely technically difficult to achieve full bonding manufacturing of the sensor array. The bonding manufacturing method for expandable surfaces cannot be applied to non-expandable surfaces, and even flexible sensors cannot be fully bonded. The online signal acquisition technology for non-expandable surfaces of three-dimensional structures has important application value for structural monitoring of key equipment such as aircraft and high-speed trains. However, as mentioned above, there are still huge challenges in full-field signal monitoring of non-expandable surfaces, especially when non-contact methods are not applicable. Summary of the invention

[0004] In view of the above problems and technical requirements, the applicant has proposed a method for manufacturing a fully bonded sensor array of a non-unfolded curved surface. The technical solution of the present application is as follows:

[0005] A method for manufacturing a fully fitted sensor array of a non-unfolded curved surface, the method comprising:

[0006] The three-dimensional surface to be monitored is modeled to obtain a surface model, the surface model includes a number of signal monitoring points, and the three-dimensional surface to be monitored is a non-expanded surface;

[0007] The area where the signal monitoring point in the surface model is located is divided into a number of surface units, and each surface unit is projected onto the plane to obtain a corresponding sub-plane, each sub-plane contains at least one signal monitoring point;

[0008] According to the position of the signal monitoring point in each sub-plane, a sub-sensor array is printed by using a direct writing printing technology, wherein the sub-sensor array includes sensor units corresponding to the positions of the signal monitoring points at each location in the sub-plane;

[0009] The printed sub-sensor arrays are respectively fitted to the corresponding surface units of the three-dimensional surface to be monitored, so that the sensing unit in each sub-sensor array is located at the signal monitoring point of the corresponding surface unit, and the sub-sensor arrays are connected to form a fully fitted sensor array for the three-dimensional surface to be monitored.

[0010] A further technical solution is that a method for printing a sub-sensor array corresponding to each sub-plane includes:

[0011] An insulating base is formed by printing, and a sensor unit and a signal lead-out line connected to the sensor unit are printed on the insulating base according to the position of the signal monitoring point in the sub-plane to obtain a sub-sensor array; when the sub-sensor array is attached to the three-dimensional surface to be monitored, the sensor unit and its signal lead-out line are insulated from the three-dimensional surface to be monitored through the insulating base.

[0012] A further technical solution is that the surface flatness of the insulating substrate reaches a flatness threshold.

[0013] A further technical solution is that the method for printing the sub-sensor array further includes:

[0014] An insulating base is formed by printing on the water-soluble film, and a sensing unit and a signal lead-out circuit thereof are printed on the insulating base. After printing is completed, the water-soluble film is dissolved to obtain a sub-sensor array.

[0015] A further technical solution is to keep the water-soluble film taut during the process of printing the insulating substrate, the sensor unit and the signal lead-out circuit.

[0016] A further technical solution is that when a sub-sensor array includes a plurality of sensing units, the signal lead-out line includes a plurality of mutually parallel first lead-out lines and a plurality of mutually parallel second lead-out lines, the first lead-out lines and the second lead-out lines intersect and are insulated from each other, and each sensing unit is located at an intersection of the first lead-out line and the second lead-out line and is connected to a first lead-out line and a second lead-out line respectively;

[0017] When printing to form the insulating base, printing is performed only on the covering area of ​​the sensing unit and the signal lead-out circuit to form an insulating base with a hollow structure.

[0018] A further technical solution is that the method for printing the sensor unit and the signal lead-out circuit on the insulating substrate comprises:

[0019] A plurality of parallel first lead-out lines are printed on an insulating substrate, an insulating intermediary layer is printed at the area on the surface of the insulating substrate covered by the second lead-out lines, and a plurality of parallel second lead-out lines are printed on the insulating intermediary layer, wherein the first lead-out lines and the second lead-out lines are insulated by the insulating intermediary layer; and various sensing units are printed at various signal monitoring points, wherein one end of each sensing unit is connected to the portion of the first lead-out line exposed relative to the insulating intermediary layer, and the other end is connected to the second lead-out line.

[0020] A further technical solution is that when the area where the signal monitoring point in the surface model is located is divided into a number of surface units, the curvature of each surface unit obtained by the division does not exceed a predetermined curvature threshold.

[0021] A further technical solution is that the structures of all the surface units obtained by cutting are the same, or there are at least two surface units with different structures; the signal monitoring points contained in all the surface units obtained by cutting are the same, or there are at least two surface units with different signal monitoring points.

[0022] A further technical solution is that when each sub-sensor array is respectively bonded to the three-dimensional curved surface to be monitored, the signal lead-out lines of each sub-sensor array are connected by conductive glue to form a fully bonded sensor array.

[0023] The beneficial technical effects of this application are:

[0024] The present application discloses a method for manufacturing a fully-fitted sensor array for a non-expanded surface, wherein the non-expanded surface to be monitored is divided into blocks using modeling software, and a sub-sensor array is printed using a direct writing printing technique for each block of the sub-sensor rate, and finally the sub-sensor array is bonded and connected to form a fully-fitted sensor array for the non-expanded surface. Each sub-sensor array can be fully bonded to the non-expanded surface in the corresponding area, thereby having good deformation consistency with the measured object. The method simply and effectively realizes the low-cost manufacturing of the fully-fitted sensor array for the non-expanded surface, and can realize large-scale signal monitoring of surfaces, especially non-expanded surfaces, thus filling the technical gap in this field. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a method flow chart of a method for manufacturing a fully-fitted sensor array of a non-unfolded curved surface disclosed in an embodiment of the present application.

[0026] Figure 2 It is a schematic diagram of a surface model in an embodiment, surface units obtained by segmentation, and corresponding sub-planes.

[0027] Figure 3 yes Figure 2 Schematic diagram of the signal monitoring points and signal lead-out lines designed in a sub-plane.

[0028] Figure 4 The flowchart is a method for manufacturing each sub-sensor array in an embodiment.

[0029] Figures 5 to 9 is a flowchart for manufacturing each sub-sensor array in an example.

[0030] Fig.10 yes Figures 5 to 9 Schematic diagram of the stacking printing of each structure in the production example shown. DETAILED DESCRIPTION

[0031] The specific implementation of the present application is further described below in conjunction with the accompanying drawings.

[0032] This application discloses a method for manufacturing a fully fitted sensor array of a non-unfolded curved surface, please refer to Figure 1 The flowchart shown in the figure is combined with Figure 2 and Figure 3 , the method comprises the following steps:

[0033] Step S1, modeling the three-dimensional surface to be monitored to obtain a surface model 1. The method provided in this application is for the three-dimensional surface to be monitored to be a non-unfolded surface, but the method can also be used when the three-dimensional surface to be monitored is an unfolded surface.

[0034] When a three-dimensional surface to be monitored has signal monitoring requirements and a fully fitting sensor array needs to be designed, the positions of the signal monitoring points on the surface of the three-dimensional surface to be detected are known, that is, it is known which positions on the three-dimensional surface to be monitored need to set up sensor units to achieve signal monitoring requirements, so the surface model 1 obtained by modeling also correspondingly includes several signal monitoring points with known positions.

[0035] In addition to the known number and positions of signal monitoring points, in some embodiments, the layout position and routing structure of the signal lead-out line used to lead out the signal of the sensor unit at the signal monitoring point on the three-dimensional surface to be monitored can also be pre-designed. The modeled surface model 1 also includes a global signal lead-out line, which covers the area where all signal monitoring points are located on the surface of the three-dimensional surface to be monitored and is used to connect the sensor unit and lead out the signal.

[0036] Step S2, divide the area where the signal monitoring point in the surface model 1 is located into a plurality of surface units 2, each surface unit 2 contains at least one signal monitoring point. In practical applications, the signal monitoring points in the surface model 1 may be distributed more dispersedly, so all areas of the surface model 1 can be divided. Alternatively, the signal monitoring points in the surface model 1 may be distributed more concentratedly, so only part of the area containing the signal monitoring point in the surface model 1 can be divided, and other areas that do not contain the signal monitoring point are not processed.

[0037] As described above, in one embodiment, the global signal lead-out line is also pre-designed, and each curved surface unit 2 obtained by cutting includes, in addition to the signal monitoring point, also a partial signal lead-out line of the pre-designed global signal lead-out line in the curved surface unit 2.

[0038] When the area including the signal monitoring point in the surface model 1 is divided into several surface units 2, the curvature of each surface unit 2 obtained by the division does not exceed a predetermined curvature threshold, which is a preset parameter, that is, the curvature of each surface unit 2 obtained by the division should not be too large.

[0039] The structures of all the surface units 2 obtained by cutting are the same, or there are at least two surface units 2 with different structures. The signal monitoring points contained in all the surface units 2 obtained by cutting are the same, or there are at least two surface units 2 with different signal monitoring points. That is, the multiple surface units 2 obtained by cutting can have the same structure or different structures, and the number and / or position of the signal monitoring points contained in each surface unit 2 can be the same or different, which has high flexibility and can be well applied to various complex structures of three-dimensional surfaces to be monitored.

[0040] Step S3, project each curved surface unit 2 onto the plane to obtain the corresponding sub-plane 3. Since each sub-plane 3 is obtained by projecting the curved surface unit 2, each sub-plane 3 also contains at least one signal monitoring point, and the number of signal monitoring points contained in each sub-plane 3 is equal to that of the curved surface unit 2 before projection, and the positions correspond one to one. Since the curvature of each curved surface unit 2 obtained by the cutting in step S2 is not too large, the shape of the sub-plane 3 obtained after projection is relatively close to the structure of the curved surface unit 2. Similarly, the sub-plane 3 also includes the pre-designed global signal lead-out line in the curved surface unit 2 and the partial signal lead-out line obtained after projection.

[0041] For example, please refer to Figure 2 and Figure 3 The lines on the surface of the surface model 1, the surface unit 2 obtained by segmentation, and the sub-plane 3 obtained by projection represent the signal monitoring points and the pre-designed global signal lead-out lines. Please refer to Figure 3The structure included in the single sub-plane 3 shown is shown in FIG. 1 , wherein each dotted line portion represents a signal monitoring point 4 where a sensing unit needs to be set, and the remaining surface lines represent a pre-designed signal lead-out line 5 .

[0042] Step S4, according to the position of the signal monitoring point in each sub-plane 3, a sub-sensor array is printed using a direct writing printing technology.

[0043] The sub-sensor array includes sensor units corresponding to the positions of the signal monitoring points in the sub-plane 3, and also includes signal lead-out lines connected to each sensor unit. In one embodiment, if the global signal lead-out line is designed in advance, the signal lead-out line in the surface unit 2 and the sub-plane 3 can be naturally determined after segmentation, and the signal lead-out line can be printed according to the pre-designed routing method. In other embodiments, if the global signal lead-out line is not designed in advance, the routing method of the signal lead-out line can be reasonably designed according to the position of the signal monitoring point in each sub-plane 3 and then printed. In actual application, considering the need to connect the signal lead-out lines of different sub-sensor arrays in the future, in order to facilitate the connection and ensure accurate signal transmission, the global signal lead-out line is generally designed first, thereby ensuring the continuity of the signal in different sub-planes 3.

[0044] The method for printing a sub-sensor array for each sub-plane 3 includes the following steps, please refer to Figure 4 The flowchart shown:

[0045] 1. Print to form an insulating substrate 7, which can be formed by printing using an insulating material such as epoxy resin. In order to ensure the fit between the subsequent sub-sensor array and the three-dimensional surface to be monitored, the surface flatness of the insulating substrate 7 is required to reach a flatness threshold. In one embodiment, in order to ensure that the flatness requirement is met, the insulating substrate 7 is printed on the water-soluble film 6, and before printing the insulating substrate 7, the water-soluble film 6 (PVA) is fully cleaned with anhydrous ethanol and absorbent cotton. Please refer to Figure 5 Schematic diagram shown.

[0046] 2. Print the sensing unit and the signal lead-out circuit connected to the sensing unit on the insulating substrate 7 according to the position of the signal monitoring point in the sub-plane 3. When using the water-soluble film 6, in order to ensure the flatness of the insulating substrate 7 and the conductive structure, keep the water-soluble film 6 tight during the printing of the insulating substrate 7, the sensing unit and the signal lead-out circuit. Then, the printed material is placed in water to dissolve the water-soluble film 6 using the dissolving property of the water-soluble film 6, thereby obtaining the desired sub-sensor array.

[0047] When printing to form the insulating base 7 , printing is performed only on the area required to be covered by the sensor unit and the signal lead-out circuit, and other areas are not printed. Therefore, the shape and area of ​​the printed insulating base 7 are generally much smaller than the area of ​​the sub-plane 3 .

[0048] Although in theory each sub-plane 3 may contain only one signal monitoring point, in actual operation, each sub-plane 3 usually contains multiple signal monitoring points, that is, a sub-sensor array includes multiple sensor units. In order to facilitate the signal lead-out of the sensor units at the multiple signal monitoring points distributed in the array, in one embodiment, the following signal lead-out line structure is adopted: the signal lead-out line includes a plurality of mutually parallel first lead-out lines and a plurality of mutually parallel second lead-out lines, the first lead-out lines and the second lead-out lines intersect and are insulated from each other, each sensor unit is respectively located at an intersection of the first lead-out line and the second lead-out line and is respectively connected to a first lead-out line and a second lead-out line, thereby the array structure formed by the intersection of the first lead-out line and the second lead-out line can conveniently connect the sensor units at different positions. Based on this signal lead-out line structure, the printed insulating substrate 7 is often an irregular shape with a hollow structure, such as Figure 5 shown.

[0049] In one embodiment, the method of printing the sensing unit and the signal lead-out line on the surface of the insulating substrate 7 comprises the following steps: printing a plurality of parallel first lead-out lines 8 on the insulating substrate 7, such as Figure 6 As shown, the end of the first lead-out line 8 has an electrode lead-out terminal 9. The insulating intermediary layer 10 is printed on the surface of the insulating substrate 7 at the area to be covered by the second lead-out line 11, as shown in FIG. Figure 7 As shown in FIG. 1 , after printing the insulating interlayer 10, a portion of the first lead-out line 8 is exposed relative to the insulating interlayer 10, and the electrode lead-out terminal 9 is also exposed relative to the insulating interlayer 10. A plurality of parallel second lead-out lines 11 are printed on the insulating interlayer 10, and the ends of the second lead-out lines 11 also have electrode lead-out terminals 12. The first lead-out line 8 and the second lead-out line 11 are insulated from each other by the insulating interlayer 10. Please refer to FIG. Figure 8 . Each sensor unit 4 is printed at each signal monitoring point. One end of each sensor unit 4 is connected to the exposed part of the first lead-out line 8 relative to the insulating interlayer 9, and the other end is connected to the second lead-out line 11. Finally, the water-soluble film 6 is dissolved to obtain a sub-sensor array. Please refer to Fig. 9 For a schematic diagram of stacked printing, please refer to Fig.10 The sensor unit 4 is connected to the lead-out line through the motor lead-out terminals 13 at both ends.

[0050] Specifically, in one embodiment, the insulating base material used is epoxy resin. Before formal printing, the pneumatic transmission device is combined with the epoxy resin packaging tube, and then the pneumatic transmission device is connected to the pneumatic control valve, and then clamped on the CNC three-axis motion platform to print on the water-soluble film 6 in a 3D printing straight writing manner. After debugging, for this type of epoxy resin, the present application sets the inner diameter of the printing needle of the printing syringe to be 260μm, the printing line spacing to be 250μm, the printing speed to be 8mm / s, and the extrusion pressure to be 0.1MPa, and better printing quality can be achieved at this time. After printing the insulating material, use an oven to dry it at 70°C for 120 minutes, and finally form an insulating base 7. The thickness of the insulating base 7 formed in this embodiment ranges from 45 to 75μm. This layer of printing can effectively ensure the flatness of the insulating base 7 and ensure the insulation between the printed circuit and the curved surface.

[0051] Then load a certain amount of conductive silver paste (EN-06B8, ENSON) into the opaque printing syringe, connect the printing syringe to the air pressure control valve, clamp it on the CNC three-axis motion platform and print it in a 3D printing straight writing manner. After debugging, for the conductive silver paste with a viscosity of about 30000cP, this embodiment sets the inner diameter of the printing needle of the printing syringe to 260μm, the printing line spacing to 250μm, the printing speed to 5mm / s, and the extrusion pressure to 0.2Mpa, at which time better printing quality can be achieved. After printing the conductive silver paste, use an oven to dry it at 70°C for 60 minutes, and finally form three first lead-out lines 8. Then use epoxy resin to print to form an insulating intermediary layer 10, and then use a similar method to print to form three second lead-out lines 11. Then, the sensor unit 4 is printed by direct writing using conductive carbon slurry. Before printing using conductive carbon slurry, it is first necessary to prepare the conductive carbon slurry with high conductivity. The preparation method is as follows: the carbon slurry material (CH-8 / MOD2, JELCON) is stirred at 2000rpm for 2 minutes using a planetary mixer and then loaded into a printing syringe, and then centrifuged at 3000rpm for 3 minutes to remove the bubbles in the carbon slurry material, so as to prepare the conductive carbon slurry used for printing and forming the sensor unit 4. Then, a certain amount of conductive carbon slurry is loaded into the opaque printing syringe, and after the printing syringe is connected to the air pressure control valve, it is clamped on the CNC three-axis motion platform and printed by 3D printing direct writing. After debugging, for the conductive carbon slurry with a viscosity of 30000cP, the inner diameter of the printing needle of the printing syringe is 260μm, the printing line spacing is 250μm, the printing speed is 5mm / s, and the extrusion pressure is 0.25Mpa. At this time, a good printing quality can be obtained. After the conductive carbon paste is printed, it is dried in an oven at 120° C. for 120 minutes to complete curing to form the sensor unit 4 .

[0052] Step S5, each printed sub-sensor array is respectively bonded to the corresponding surface unit 2 of the three-dimensional surface to be monitored, so that the sensor unit in each sub-sensor array is located at the signal monitoring point of the corresponding surface unit 2. When the sub-sensor array is bonded to the three-dimensional surface to be monitored, the sensor unit and its signal lead-out circuit are insulated from the three-dimensional surface to be monitored by the insulating substrate 7. And each sub-sensor array is connected to form a fully bonded sensor array of the three-dimensional surface to be monitored. Specifically, the signal lead-out circuits of each sub-sensor array are connected by conductive glue to form a fully bonded sensor array. The conductive glue used has good conductivity. For example, LX-30 epoxy conductive glue can be used. The electrode lead-out terminals 9 at the end of the first lead-out circuit 8 in each sub-sensor array are connected in sequence as needed, and the electrode lead-out terminals 12 at the end of the second lead-out circuit 11 are connected in sequence.

[0053] 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 method for manufacturing a fully fitted sensor array on a non-unfolded surface, It is characterized in that The method comprises: Modeling the three-dimensional surface to be monitored to obtain a surface model, wherein the surface model includes a plurality of signal monitoring points, and the three-dimensional surface to be monitored is a non-expanded surface; Dividing the area where the signal monitoring point in the surface model is located into a plurality of surface units, and projecting each surface unit onto a plane to obtain a corresponding sub-plane, each sub-plane containing at least one signal monitoring point; According to the position of the signal monitoring point in each sub-plane, a sub-sensor array is printed by using a direct writing printing technology, wherein the sub-sensor array includes sensor units corresponding to the positions of the signal monitoring points at various locations in the sub-plane; The printed sub-sensor arrays are respectively attached to the corresponding surface units of the three-dimensional curved surface to be monitored, so that the sensing units in each sub-sensor array are located at the signal monitoring points of the corresponding curved surface units, and the signal lead-out lines of each sub-sensor array are connected by conductive glue to form a fully attached sensor array of the three-dimensional curved surface to be monitored; The method for printing a sub-sensor array corresponding to each sub-plane includes: printing on a water-soluble film to form an insulating base, wherein the surface flatness of the insulating base reaches a flatness threshold; printing a sensor unit and a signal lead-out circuit connected to the sensor unit on the insulating base according to the position of a signal monitoring point in the sub-plane, and keeping the water-soluble film taut during printing of the insulating base, the sensor unit and the signal lead-out circuit; dissolving the water-soluble film after printing to obtain a sub-sensor array; and when the sub-sensor array is attached to the three-dimensional curved surface to be monitored, the sensor unit and its signal lead-out circuit are insulated from the three-dimensional curved surface to be monitored through the insulating base.

2. The method according to claim 1, It is characterized in that When a sub-sensor array includes a plurality of sensing units, the signal lead-out line includes a plurality of mutually parallel first lead-out lines and a plurality of mutually parallel second lead-out lines, the first lead-out lines and the second lead-out lines intersect and are insulated from each other, and each sensing unit is located at an intersection of the first lead-out line and the second lead-out line and is connected to a first lead-out line and a second lead-out line respectively; When printing to form the insulating base, printing is performed only on the covering area of ​​the sensing unit and the signal lead-out circuit to form the insulating base with a hollow structure.

3. The method according to claim 2, It is characterized in that The method of printing a sensor unit and a signal lead-out circuit on the insulating substrate comprises: A plurality of parallel first lead-out lines are printed on the insulating base, an insulating intermediary layer is printed at the area on the surface of the insulating base covered by the second lead-out line, and a plurality of parallel second lead-out lines are printed on the insulating intermediary layer, wherein the first lead-out line and the second lead-out line are insulated by the insulating intermediary layer; and each sensing unit is printed at each signal monitoring point, wherein one end of each sensing unit is connected to the portion of the first lead-out line exposed relative to the insulating intermediary layer, and the other end is connected to the second lead-out line.

4. The method according to claim 1, It is characterized in that When the area where the signal monitoring point in the curved surface model is located is divided into a plurality of curved surface units, the curvature of each curved surface unit obtained by the division does not exceed a predetermined curvature threshold.

5. The method according to claim 1, It is characterized in that The structures of all the surface units obtained by cutting are the same, or there are at least two surface units with different structures; the signal monitoring points contained in all the surface units obtained by cutting are the same, or there are at least two surface units with different signal monitoring points.

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