Omnidirectional strain monitoring system and preparation method of sensing module

Abstract

The invention provides an omni-directional strain monitoring system, which comprises a sensing module, the sensing module comprises a hydrogel substrate, a plurality of sensing units are arranged in the hydrogel substrate and are distributed in a mutually associated angle configuration mode, each sensing unit at least comprises a sensing part and a transmission part, the sensing part is used for generating an initial electric signal according to the received stress, and the transmission part is used for transmitting the initial electric signal to the hydrogel substrate; the transmission part is used for reading and transmitting the initial electric signal; the control module comprises an upper computer and a stress neural network, the upper computer is used for processing the initial electric signals corresponding to the sensing units into resistance change rates matched with the stress neural network and inputting the resistance change rates to the stress neural network, and the stress neural network obtains a stress identification result through multiple target electric signal values and angle configuration modes. The stress at least comprises stress values and stress directions. According to the scheme, omni-directional strain monitoring is realized, and strain information can be effectively captured no matter which direction the stress is applied, so that various complex stress environments are adapted, and more comprehensive and reliable data support is provided for design and safety evaluation of related structures.

Description

Technical Field

[0001] The present application relates to the field of sensor technology, and in particular to a method for preparing an omnidirectional strain monitoring system and a sensor module. Background Art

[0002] Accurate monitoring of stress and strain is crucial in many engineering fields and scientific research. Traditional strain monitoring methods often have many limitations. For example, in the field of aerospace, complex structures of aircraft are subject to multi-directional forces during flight, or in mechanical engineering, complex mechanical parts are faced with complex stress environments during operation. Traditional methods cannot fully perceive changes in stress. From this example, it can be seen that traditional strain monitoring systems can usually only measure in limited directions under complex stress environments, which makes it difficult to meet the needs of simultaneous monitoring of stress in multiple directions. Summary of the invention

[0003] In view of the above-mentioned defects or deficiencies in the prior art, the present application aims to provide an omnidirectional strain monitoring system and a method for preparing a sensor module to meet the needs of simultaneous monitoring of multi-directional stresses.

[0004] In a first aspect, the present application proposes an omnidirectional strain monitoring system, comprising:

[0005] A sensing module, wherein the sensing module comprises a hydrogel substrate, wherein the hydrogel substrate has a plurality of sensing units, wherein the plurality of sensing units are distributed in an interrelated angular configuration, wherein each of the sensing units comprises at least a sensing portion and a transmission portion, wherein the sensing portion is used to generate an initial electrical signal according to the stress received, and the transmission portion is used to read and transmit the initial electrical signal;

[0006] A control module, the control module at least includes a host computer and a stress neural network, the host computer is used to process the initial electrical signal corresponding to each of the sensing units into a resistance change rate that matches the stress neural network, and input multiple resistance change rates into the stress neural network; the stress neural network obtains a stress recognition result through multiple target electrical signal values ​​and the angle configuration method, and the stress recognition result at least includes a stress value and a stress direction.

[0007] According to the technical solution provided in the embodiment of the present application, there are three sensing units in the hydrogel substrate, and the three sensing units are distributed in a Y-shaped angular configuration.

[0008] According to the technical solution provided in the embodiment of the present application, the sensing part is a conductive elastomer prepared by mixing platinum-catalyzed silicone rubber with carbon black.

[0009] According to the technical solution provided in the embodiment of the present application, the transmission unit includes a microchip and an RFID antenna, the microchip is used to read the initial electrical signal value, and the RFID antenna is used to transmit the initial electrical signal value.

[0010] According to the technical solution provided in the embodiment of the present application, the sensor module is also integrated with an RFID tag, and the RFID tag contains a specific identification code.

[0011] According to the technical solution provided in the embodiment of the present application, the control module further includes an RFID reader, which is used to read the initial electrical signal value transmitted from the RFID antenna and send the initial electrical signal value to the host computer.

[0012] According to the technical solution provided in the embodiment of the present application, the monitoring system also includes a storage module, which is electrically connected to the control module and is used to store stress data, and the stress data at least includes the initial electrical signal, the resistance change rate and the stress identification result.

[0013] According to the technical solution provided in the embodiment of the present application, the monitoring system also includes a display module, and the display module is used to display the real-time stress identification result.

[0014] In a second aspect, the present application provides a method for preparing a sensor module, for preparing the sensor module as described above, comprising preparing a hydrogel substrate, wherein the preparation of the hydrogel substrate comprises the following steps:

[0015] Adding 10-20 wt % acrylamide particles and 5-10 wt % soluble salt particles into deionized water, and stirring magnetically at room temperature until the acrylamide and the soluble salt particles are completely dissolved to obtain an acrylamide mixed solution;

[0016] Adding 0.16-0.18 wt % of ammonium persulfate and 0.08 wt % of methylenebisacrylamide to the acrylamide mixed solution, and then adding 0.26 wt % of tetramethylethylenediamine, and pouring into a mold after magnetic stirring to obtain an uncrosslinked hydrogel precursor solution;

[0017] The hydrogel precursor solution is kept in an environment of 60° C. for 3 hours to complete the cross-linking of the hydrogel and obtain the hydrogel substrate.

[0018] According to the technical solution provided in the embodiment of the present application, the following steps are also included:

[0019] Carbon black and ecoflex A solution were mixed in a weight ratio of 1:10, and stirred using a magnetic stirrer to obtain a first mixed solution;

[0020] adding an ecoflex B solvent having the same weight as the ecoflex A solution to the first mixed solution, and stirring to obtain a second mixed solution;

[0021] The second mixed solution is placed in a vacuum degasser for degassing to obtain a preliminary solution;

[0022] Using a casting mold, casting the preparatory liquid and heating it in an oven at 60° C. for thirty minutes to obtain the sensing part;

[0023] Placing the sensing part in the mold and connecting it to the transmission part using a wire;

[0024] The hydrogel substrate is used for further packaging to obtain the sensing module.

[0025] In summary, the present application proposes an omnidirectional strain monitoring system, comprising:

[0026] A sensing module, wherein the sensing module comprises a hydrogel substrate, wherein the hydrogel substrate has a plurality of sensing units, wherein the plurality of sensing units are distributed in an interrelated angular configuration, wherein each of the sensing units comprises at least a sensing portion and a transmission portion, wherein the sensing portion is used to generate an initial electrical signal according to the stress received, and the transmission portion is used to read and transmit the initial electrical signal;

[0027] A control module, the control module at least includes a host computer and a stress neural network, the host computer is used to process the initial electrical signal corresponding to each of the sensing units into a resistance change rate that matches the stress neural network, and input multiple resistance change rates into the stress neural network; the stress neural network obtains a stress recognition result through multiple target electrical signal values ​​and the angle configuration method, and the stress recognition result at least includes a stress value and a stress direction.

[0028] Compared with the prior art, the beneficial effects of the present application are as follows: the present application realizes true omnidirectional strain monitoring through a unique sensing module design, in which multiple sensing units in the hydrogel substrate are distributed in an interrelated angular configuration. No matter from which direction the stress is applied, the system can effectively capture the strain information, thereby adapting to various complex stress environments, such as the aerospace and mechanical engineering fields mentioned above, and providing more comprehensive and reliable data support for the design and safety assessment of related structures.

[0029] Secondly, from the performance point of view of the sensing unit, each sensing unit includes at least a sensing part and a transmission part. The sensing part can generate an initial electrical signal according to the stress, and the transmission part can efficiently read and transmit the signal, which ensures the accurate collection and rapid transmission of strain information.

[0030] Furthermore, in terms of data processing, the host computer in the control module processes the initial electrical signal into a resistance change rate that matches the stress neural network and inputs it into the stress neural network. This processing method is efficient and accurate, and the host computer can convert complex electrical signals into resistance change rate data that is more suitable for analysis. The stress neural network combines multiple resistance change rates and the angle configuration of the sensing unit to accurately obtain stress identification results, including stress value and stress direction. This not only improves data processing efficiency, but also greatly improves the accuracy of stress identification.

[0031] In addition, the system also has advantages in reusability and cost control. The unique hydrogel substrate and sensing unit design may provide conditions for the reuse of sensing modules, reduce the cost of frequent replacement of sensing devices, and improve the economy and practicality of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic diagram of the structure of an omnidirectional strain monitoring system provided in an embodiment of the present application;

[0033] Figure 2 A schematic diagram of the structure of the sensor module provided in the embodiment of the present application;

[0034] Figure 3 A schematic diagram of direction recognition of an omnidirectional strain monitoring system provided in an embodiment of the present application;

[0035] Figure 4 A flowchart of the steps of the method for using the omnidirectional strain monitoring system provided in an embodiment of the present application.

[0036] The text annotations in the figure represent:

[0037] 1. Hydrogel substrate; 2. Sensing part; 3. Transmission part; 4. Wire; 5. Sensing module; 6. Control module. DETAILED DESCRIPTION

[0038] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It is also necessary to explain that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0039] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0040] Example 1

[0041] As mentioned in the background technology, in order to solve the problems in the prior art, this application proposes an omnidirectional strain monitoring system, please refer to Figure 1 As shown, including:

[0042] A sensing module 5, wherein the sensing module 5 comprises a hydrogel substrate 1, wherein the hydrogel substrate 1 has a plurality of sensing units, wherein the plurality of sensing units are distributed in an interrelated angular configuration, wherein each of the sensing units comprises at least a sensing portion 2 and a transmission portion 3, wherein the sensing portion 2 is used to generate an initial electrical signal according to the stress received, and the transmission portion 3 is used to read and transmit the initial electrical signal;

[0043] Furthermore, the sensing part 2 is a conductive elastomer prepared by mixing platinum-catalyzed silicone rubber with carbon black.

[0044] Specifically, after the conductive elastomer is subjected to external stress, its resistance will change with the change of strain. When the conductive elastomer is deformed by external force, its internal conductive network structure will change, resulting in a change in resistance value. According to relevant theories such as strain resistance effect, there is a certain mathematical relationship between strain and resistance change.

[0045] For this mathematical relationship, specifically, in the system, the strain information of the sensing unit is first converted into the initial electrical signal, which can be a voltage, a current or other electrical quantity. Through the characteristics of known electrical measurement circuits (such as a Wheatstone bridge, etc.), the relationship between the initial electrical signal and the resistance of the sensing unit can be established. For example, in a Wheatstone bridge, when the resistance of the sensing unit changes, the voltage signal output by the bridge will change accordingly. By measuring the change in this voltage signal, the change in the resistance of the sensing unit can be inferred.

[0046] Specifically, the interrelated angular configurations highlight the ability of the sensing units to work together to achieve multi-directional information collection through specific angular configurations.

[0047] In a preferred embodiment, please refer to Figure 2 As shown, the hydrogel substrate 1 has three sensing units, and the three sensing units are distributed in a Y-shaped angle configuration.

[0048] Specifically, the Y-shaped distribution is one of the angle configurations used to achieve multi-directional strain information collection. This description may also include other distributions to achieve similar functions.

[0049] A control module 6, wherein the control module 6 at least includes a host computer and a stress neural network, wherein the host computer is used to process the initial electrical signals corresponding to each of the sensing units into a resistance change rate that matches the stress neural network, and input a plurality of the resistance change rates into the stress neural network; the stress neural network obtains a stress recognition result through a plurality of the target electrical signal values ​​and the angle configuration, and the stress recognition result at least includes a stress value and a stress direction.

[0050] Specifically, multiple sensing units are arranged in the sensing module 5 in a distributed manner according to interrelated angular configurations, and these angles determine the orientation of each sensing unit in space. For example, one sensing unit may be placed at 0° to the horizontal direction, another may be at 30°, a third may be at 60°, and so on. When stress is applied to the entire system, due to the differences in these angles, the stress components borne by each sensing unit will be different, resulting in changes in the readings. The stress neural network will use this association between angles and readings to determine the direction of stress.

[0051] In a preferred embodiment, the transmission unit 3 includes a microchip and an RFID antenna, the microchip is used to read the initial electrical signal value, and the RFID antenna is used to transmit the initial electrical signal value.

[0052] In a preferred embodiment, the sensor module 5 is also integrated with an RFID tag, and the RFID tag contains a specific identification code.

[0053] In a preferred embodiment, the control module 6 further includes an RFID reader, and the RFID reader is used to read the initial electrical signal value transmitted from the RFID antenna and send the initial electrical signal value to the host computer.

[0054] In a preferred embodiment, the monitoring system further includes a storage module, which is electrically connected to the control module 6 and is used to store stress data, wherein the stress data at least includes the initial electrical signal, the resistance change rate and the stress identification result.

[0055] In a preferred embodiment, the monitoring system further comprises a display module, and the display module is used to display the real-time stress identification result.

[0056] Example 2

[0057] On the basis of Example 1, this example proposes a method for preparing a sensor module 5, which is used to prepare the sensor module 5 as described in Example 1, including preparing a hydrogel substrate 1, wherein the preparation of the hydrogel substrate 1 includes the following steps:

[0058] Adding 10-20 wt % acrylamide particles and 5-10 wt % soluble salt particles into deionized water, and stirring magnetically at room temperature until the acrylamide and the soluble salt particles are completely dissolved to obtain an acrylamide mixed solution;

[0059] Adding 0.16-0.18 wt % of ammonium persulfate and 0.08 wt % of methylenebisacrylamide to the acrylamide mixed solution, and then adding 0.26 wt % of tetramethylethylenediamine, and pouring into a mold after magnetic stirring to obtain an uncrosslinked hydrogel precursor solution;

[0060] The hydrogel precursor solution was kept in an environment of 60° C. for 3 hours to complete the cross-linking of the hydrogel, thereby obtaining the hydrogel substrate 1.

[0061] In a preferred embodiment, the following steps are also included:

[0062] Carbon black and ecoflex A solution were mixed in a weight ratio of 1:10, and stirred using a magnetic stirrer to obtain a first mixed solution;

[0063] Specifically, 0.5 g of carbon black and 5 g of ecoflex A solution were added, and a magnetic stirrer was used to stir for 3 hours.

[0064] adding an ecoflex B solvent having the same weight as the ecoflex A solution to the first mixed solution, and stirring to obtain a second mixed solution;

[0065] Specifically, ecoflex B solvent was 5 grams.

[0066] The second mixed solution is placed in a vacuum degassing machine for degassing to obtain a preliminary solution; specifically, the second mixed solution is placed in a vacuum degassing machine for degassing for 5 minutes.

[0067] Using a casting mold, the preparatory liquid is cast and placed in an oven at 60° C. for heating for thirty minutes to obtain the sensing part 2;

[0068] The sensing part 2 is placed in the mold, and connected to the transmission part 3 using a wire 4;

[0069] The hydrogel substrate 1 is used for further packaging to obtain the sensor module 5 .

[0070] Specifically, ecoflex is a platinum-catalyzed rubber, similar to AB glue, and is divided into ecoflex A solution and ecoflex B solvent. The ecoflex A solution and ecoflex B solvent are mixed to obtain a preparatory liquid, and the preparatory liquid is heated and solidified in an oven to obtain the sensing part 2 made of platinum-catalyzed rubber. Due to its good flexibility, flexible sensors can be made, which can adapt to different monitoring surface shapes and maintain good performance in complex strain environments. For example, in the above-mentioned omnidirectional strain monitoring system, it may be used as part of the sensing unit material to achieve accurate monitoring of various strains.

[0071] Example 3

[0072] Based on Example 1, this example proposes a method for using an omnidirectional strain monitoring system. Figure 4 As shown, the method of use includes the following steps:

[0073] S1, fixing the sensor module 5 at the point to be detected;

[0074] S2, the initial electrical signal collected by the sensor module 5 is processed by the microchip and then sent by the RFID antenna, and the RFID reader sends the collected initial electrical signal to the host computer in real time for preprocessing;

[0075] S3. The stress neural network uses the resistance change rate processed by the host computer to perform stress recognition, and uses a multi-input and multi-output stress neural network for training so that it can realize strain direction and size recognition.

[0076] The present invention is an omnidirectional strain monitoring system using a sensor module with a strain direction differential response structure, please refer to Figure 3 It can be seen that the recognition accuracy of the omnidirectional strain monitoring system is 5°. The module has extremely high sensitivity to strains in a specific direction, and has higher recognition accuracy than other strain sensors. Moreover, the use of the RFID antenna as a data transmission tool simplifies the difficulty of preparation and data collection. The wireless omnidirectional strain monitoring sensor has the characteristics of being integrated, stretchable, and omnidirectional, and can detect tiny strains in all directions. The preparation process is simple, the production cost is low, it is reusable, easy to install, and has better adaptability to curved surfaces. In addition, stress recognition is realized by using neural networks, and the data collected by the sensor is processed and fused through neural networks to make judgments on the stress direction and displacement and synchronize the results to the display device for real-time monitoring. At the same time, the data can also be uploaded to the cloud for big data analysis.

[0077] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and its core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression and the objective existence of infinite specific structures, ordinary technicians in this technical field can make several improvements, modifications or changes without departing from the principles of the present invention, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. An omnidirectional strain monitoring system, characterized in that: include: A sensing module (5), the sensing module (5) comprising a hydrogel substrate (1), the hydrogel substrate (1) having a plurality of sensing units therein, the plurality of sensing units being distributed in an interrelated angular configuration, each of the sensing units comprising at least a sensing portion (2) and a transmission portion (3), the sensing portion (2) being used to generate an initial electrical signal according to the stress received, and the transmission portion (3) being used to read and transmit the initial electrical signal; A control module (6), the control module (6) comprising at least a host computer and a stress neural network, the host computer being used to process the initial electrical signal corresponding to each of the sensing units into a resistance change rate matching the stress neural network, and input a plurality of the resistance change rates into the stress neural network; The stress neural network obtains a stress identification result through the multiple target electrical signal values ​​and the angle configuration mode, and the stress identification result at least includes a stress value and a stress direction.

2. The omnidirectional strain monitoring system according to claim 1, characterized in that: The hydrogel substrate (1) has three sensing units in it, and the three sensing units are distributed in a Y-shaped angular configuration.

3. The omnidirectional strain monitoring system according to claim 1, characterized in that: The induction part (2) is a conductive elastomer prepared by mixing platinum-catalyzed silicone rubber with carbon black.

4. The omnidirectional strain monitoring system according to claim 1, characterized in that: The transmission part (3) comprises a microchip and an RFID antenna, wherein the microchip is used to read the initial electrical signal value, and the RFID antenna is used to transmit the initial electrical signal value.

5. The omnidirectional strain monitoring system according to claim 4, characterized in that: The sensor module (5) is also integrated with an RFID tag, and the RFID tag contains a specific identification code.

6. The omnidirectional strain monitoring system according to claim 5, characterized in that: The control module (6) further comprises an RFID reader, which is used to read the initial electrical signal value transmitted from the RFID antenna and send the initial electrical signal value to the host computer.

7. The omnidirectional strain monitoring system according to claim 1, characterized in that: The monitoring system also includes a storage module, which is electrically connected to the control module (6) and is used to store stress data, wherein the stress data at least includes the initial electrical signal, the resistance change rate and the stress identification result.

8. The omnidirectional strain monitoring system according to claim 1, characterized in that: The monitoring system also includes a display module, and the display module is used to display the real-time stress identification result.

9. A method for preparing a sensor module (5), for preparing the sensor module (5) as claimed in any one of claims 1 to 8, characterized in that: The method comprises preparing a hydrogel substrate (1), wherein the preparation of the hydrogel substrate (1) comprises the following steps: Adding 10-20 wt % acrylamide particles and 5-10 wt % soluble salt particles into deionized water, and stirring magnetically at room temperature until the acrylamide and the soluble salt particles are completely dissolved to obtain an acrylamide mixed solution; Adding 0.16-0.18 wt % of ammonium persulfate and 0.08 wt % of methylenebisacrylamide to the acrylamide mixed solution, and then adding 0.26 wt % of tetramethylethylenediamine, and pouring into a mold after magnetic stirring to obtain an uncrosslinked hydrogel precursor solution; The hydrogel precursor solution is kept in an environment of 60° C. for 3 hours to complete the cross-linking of the hydrogel, thereby obtaining the hydrogel substrate (1).

10. The method for preparing the sensor module (5) according to claim 9, characterized in that: The following steps are also included: Carbon black and ecoflex A solution were mixed in a weight ratio of 1:10, and stirred using a magnetic stirrer to obtain a first mixed solution; adding an ecoflex B solvent having the same weight as the ecoflex A solution to the first mixed solution, and stirring to obtain a second mixed solution; The second mixed solution is placed in a vacuum degasser for degassing to obtain a preliminary solution; Using a casting mold, casting the preparatory liquid and heating it in an oven at 60° C. for thirty minutes to obtain the sensing part (2); The sensing part (2) is placed in the mold, and connected to the transmission part (3) using a wire (4); The hydrogel substrate (1) is used for further packaging to obtain the sensor module (5).

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