A three-dimensional stress monitoring device based on a flexible sensor array and a reconstruction method

Abstract

The present application relates to the technical fields of mechanical test monitoring and sensing detection, and discloses a three-dimensional stress monitoring device and reconstruction method based on a flexible sensor array, comprising: a mechanical loading and clamping assembly, which defines an accommodating cavity inside for placing a test piece, and is provided with a guide advancing rod on the side surface for matching the flexible sensor array with the test piece; a sensing acquisition and three-dimensional reconstruction assembly is arranged outside the mechanical loading and clamping assembly and is electrically connected with the flexible sensor array, and is used for reconstructing a three-dimensional stress transmission response field. The mechanical loading and clamping assembly, the flexible sensor array, the sensing acquisition and three-dimensional reconstruction assembly and the three-dimensional reconstruction method are integrally designed, so that the stable acquisition, spatial mapping and three-dimensional reconstruction of the mechanical response of different measuring points of the test piece during loading can be realized.

Description

Technical Field

[0001] This invention relates to the field of mechanical testing monitoring and sensing technology, and in particular to a three-dimensional stress monitoring device and reconstruction method based on a flexible sensor array. Background Technology

[0002] The stress transfer and damage evolution characteristics of rocks, concrete, cemented infills, similar materials, and other engineering materials under load are important bases for analyzing material load-bearing capacity, failure mechanisms, and structural stability. In conventional mechanical testing, the overall load, displacement, and stress-strain curves are usually obtained through testing machines, and auxiliary monitoring of the specimen's loading process is carried out by combining strain gauges, acoustic emission, digital image correlation methods, or local sensors. Among these methods, strain gauge monitoring is mostly based on single points or a small number of measuring points, making it difficult to reflect the differences in stress transfer between different locations on the specimen; acoustic emission methods can reflect internal damage activity, but it is difficult to directly correspond to the stress response at a specific spatial location; digital image correlation methods mainly rely on specimen surface images, which are greatly affected by the field of view, occlusion conditions, and lighting environment; traditional pressure sensors or rigid clamping monitoring structures can easily change the original force boundaries of the specimen during installation, especially in lateral monitoring, where excessive clamping may impose additional constraints on the specimen, thus affecting the accuracy of the test results.

[0003] In recent years, flexible sensors, due to their characteristics of flexible bonding, multi-point sensing, and array arrangement, have been increasingly used for monitoring material surface pressure, contact state, and local deformation response, potentially solving the aforementioned technical problems. However, the application of flexible sensors in specimen mechanical loading tests still faces certain technical obstacles: on the one hand, flexible sensors are prone to misalignment, reverse installation, slippage, or wrinkling when mounted on the specimen surface, leading to inconsistencies between the measurement point position and spatial coordinates; on the other hand, flexible sensors require a certain preload to bond with the specimen surface, but insufficient preload will cause contact instability, while excessive preload will impose lateral constraints on the specimen. Furthermore, data collected by multiple flexible sensing units requires channel identification, baseline subtraction, synchronous acquisition, spatial coordinate mapping, and load verification. Existing testing devices have failed to integrate the mechanical clamping structure, flexible sensing array, data acquisition module, and 3D reconstruction method into a single design. Therefore, existing mechanical testing monitoring technologies still struggle to achieve multi-point, multi-directional, and low-interference local mechanical response acquisition during specimen loading, and also find it difficult to further transform the discrete data obtained by flexible sensors into a 3D stress transfer response spectrum with spatial coordinate attributes.

[0004] In view of this, how to provide a three-dimensional stress transfer monitoring device and reconstruction method for specimens based on a flexible sensor array, so as to achieve stable acquisition, spatial mapping and three-dimensional reconstruction of the mechanical response at different measuring points during the loading process of the specimen, is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a three-dimensional stress monitoring device and reconstruction method based on a flexible sensor array to solve the problems existing in the prior art.

[0006] To achieve the above objectives, the present invention provides a three-dimensional stress monitoring device based on a flexible sensor array, comprising: A mechanical loading and clamping assembly has an internal cavity for placing a specimen. An upper loading bearing plate is slidably mounted on the top of the assembly in a vertical direction to apply a longitudinal load to the specimen. A guide push rod is mounted on the side of the assembly, and a flexible sensor array is mounted on the end of the guide push rod closest to the specimen. The guide push rod is used to bring the flexible sensor array into contact with the specimen, and the flexible sensor array is used to collect the mechanical response signal of the specimen. The sensing and acquisition and three-dimensional reconstruction component is disposed outside the mechanical loading and clamping component and electrically connected to the flexible sensor array, and is used to reconstruct the three-dimensional stress transmission response field.

[0007] Furthermore, the mechanical loading and clamping assembly includes: A bottom support plate, with top support plates spaced apart above it; A lateral support plate is disposed between the bottom support plate and the top support plate, and the bottom support plate, the top support plate and the lateral support plate together form the receiving cavity; a sealed sliding bearing is provided on the top support plate, and the upper loading pressure plate is slidably connected to the sealed sliding bearing; a threaded hole is provided on the lateral support plate, the tail end of the guide push rod is connected to the threaded adjusting rod, the threaded adjusting rod is engaged with the threaded hole, and the sensing acquisition and three-dimensional reconstruction component is disposed on the outside of the lateral support plate; The lower pressure plate is disposed within the receiving cavity and located on the bottom support plate; A lateral force transmission pressure plate is provided, with the front end of the guide push rod connected to the lateral force transmission pressure plate. The lateral force transmission pressure plate is embedded in a flexible bonding pad, and the flexible sensor array is disposed on the side of the flexible bonding pad close to the specimen.

[0008] Furthermore, the sensing acquisition and 3D reconstruction component includes: A monitoring and sensing integration box is disposed on the outside of the lateral support plate. The monitoring and sensing integration box contains: a flexible sensing access chip, a signal conditioning chip, a multi-channel synchronous acquisition chip, a load displacement synchronous access chip, a pre-tightening baseline correction chip, a spatial coordinate mapping chip, a load verification chip, and a 3D reconstruction and communication chip. The flexible sensing access chip is electrically connected to the flexible sensor array. The signal conditioning chip is electrically connected to the flexible sensing access chip. The multi-channel synchronous acquisition chip is electrically connected to both the signal conditioning chip and the load displacement synchronous access chip. The pre-tightening baseline correction chip, the spatial coordinate mapping chip, and the load verification chip are electrically connected to the multi-channel synchronous acquisition chip. The 3D reconstruction and communication chip is electrically connected to the pre-tightening baseline correction chip, the spatial coordinate mapping chip, and the load verification chip.

[0009] Furthermore, it also includes a power supply and heat dissipation component, which includes a power management chip, an energy storage power supply module, and a miniature cooling fan disposed within the monitoring and sensing integration box; the energy storage power supply module is electrically connected to the power management chip, and the power management chip is electrically connected to a flexible sensing access chip, a signal conditioning chip, a multi-channel synchronous acquisition chip, a load displacement synchronous access chip, a pre-tightening baseline correction chip, a spatial coordinate mapping chip, a load verification chip, a three-dimensional reconstruction and communication chip, and the miniature cooling fan; the monitoring and sensing integration box has an air outlet, and the miniature cooling fan is disposed at the air outlet.

[0010] Furthermore, the monitoring sensor integration box is magnetically attached to the outside of the lateral support plate.

[0011] Furthermore, the threaded adjusting rod and / or the guide pushing rod are provided with multiple adjusting connection holes. The adjusting connection holes are elongated hole structures arranged along the length direction of the threaded adjusting rod. A hinge pin is inserted into the adjusting connection hole to make the threaded adjusting rod and the guide pushing rod slide together. A preload spring is provided between the threaded adjusting rod and the guide pushing rod. The preload spring has an elastic tendency to push the guide pushing rod toward the specimen.

[0012] Furthermore, the flexible sensor array is detachably connected to an upper sensor array and a lower sensor array. The upper sensor array is arranged between the specimen and the upper loading pressure plate, and the lower sensor array is arranged between the specimen and the lower pressure plate.

[0013] Furthermore, a leveling ball head is provided on the upper loading pressure plate, and a lateral leveling ball head is provided at the end of the guide push rod near the lateral force transmission pressure plate.

[0014] Furthermore, the threaded adjusting rod and the guide push rod are provided with a wiring groove along the axis, and the wires of the flexible sensor array are led outward along the wiring groove.

[0015] This invention also provides a three-dimensional stress reconstruction method based on a flexible sensor array, using a three-dimensional stress monitoring device based on a flexible sensor array, comprising the following steps: S1: The flexible sensor array is brought into contact with the specimen by adjusting the threaded rod and the guide push rod. The external loading device applies a longitudinal load to the specimen through the upper loading pressure plate. The flexible sensor array acquires the mechanical response signals of different measuring points during the loading process of the specimen, and inputs the mechanical response signals to the flexible sensing access chip. The flexible sensing access chip performs channel identification on the signals of each measuring point according to the sensing unit number, forming an original sensing data frame with the measuring point number attribute. S2: The signal conditioning chip receives the original sensing data frame and amplifies, filters, suppresses zero drift, and removes abnormal pulses from each channel signal to form a conditioned sensing data frame; the multi-channel synchronous acquisition chip synchronously samples the conditioned sensing data frame and assigns a unified time identifier to the data of each channel at the same sampling time to form a time-synchronized sensing data frame. S3: The load displacement synchronization access chip receives the load data and displacement data output by the external loading device, and matches them with the time synchronization sensing data frame according to the unified time identifier to form a load synchronization data frame containing sensing response, load information and displacement information. S4: The pre-tightening baseline correction chip calls the initial pre-tightening baseline data obtained by the flexible sensor array before the external loading device loads, and performs point-by-point baseline subtraction on the sensing response of each measuring point in the loading synchronization data frame to obtain the net response data frame of each measuring point relative to the initial bonding state. S5: The spatial coordinate mapping chip maps the measurement point data in the net response data frame to the corresponding three-dimensional spatial coordinate position of the specimen according to the measurement point number, installation orientation and array arrangement of the flexible sensor array, forming a spatiotemporal mapping data frame containing time stamp, measurement point number, spatial coordinate and net response value. S6: The load verification chip performs load constraint verification on the spatiotemporal mapping data frame based on the load data accessed by the load displacement synchronous access chip; when there is a systematic deviation between the net response data of each measuring point and the overall load data, the load verification chip normalizes and corrects the net response value of each measuring point based on the load data to form the verified spatiotemporal mechanical response data frame. S7: The three-dimensional reconstruction and communication chip receives the verified spatiotemporal mechanical response data frame, and uses the three-dimensional geometric model of the specimen as the reconstruction object. It takes the spatial coordinates corresponding to each measurement point as boundary or surface constraint nodes, and generates the equivalent response value of the corresponding position inside the specimen through spatial interpolation, neighborhood weighting and voxel filling, forming a three-dimensional stress transfer response field. S8: The 3D reconstruction and communication chip organizes the continuously formed 3D stress transfer response field in stages according to loading time, load level or displacement stage, and generates 3D stress transfer evolution maps at different times or different loading stages. S9: The three-dimensional reconstruction and communication chip extracts the maximum, minimum and average values ​​from the three-dimensional stress transmission evolution map, generates the maximum value monitoring curve in chronological order, and outputs the three-dimensional stress transmission evolution map, maximum, minimum, average and maximum value monitoring curve to the external display terminal.

[0016] The present invention discloses the following technical effects: This invention integrates mechanical loading and clamping components, flexible sensor arrays, sensing acquisition and three-dimensional reconstruction components, and three-dimensional reconstruction methods into a single design, enabling stable acquisition, spatial mapping, and three-dimensional reconstruction of the mechanical responses at different measurement points during specimen loading. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is an exploded view of the structure of the present invention; Figure 3 This is a schematic diagram of the sensing acquisition and 3D reconstruction components; Figure 4 This is a schematic diagram illustrating the monitoring effect of the present invention (showing the pressure detected by the flexible sensor array). Figure 5 This is a schematic diagram illustrating the monitoring effect of the present invention (showing three-dimensional pressure); The components include: 1. Mechanical loading and clamping assembly; 101. Bottom support plate; 102. Top support plate; 103. Lateral support plate; 104. Upper loading pressure plate; 105. Lower pressure plate; 106. Threaded adjusting rod; 107. Guide push rod; 108. Hinge pin; 109. Lateral force transmission pressure plate; 110. Flexible fitting pad; 111. Flexible sensor array; 112. Fixing screw; 113. Sealed sliding bearing; 2. Sensing acquisition and 3D reconstruction assembly; 201 1. Monitoring and sensing integration box; 202. Flexible sensing access chip; 203. Signal conditioning chip; 204. Multi-channel synchronous acquisition chip; 205. Load displacement synchronous access chip; 206. Pre-tightening baseline correction chip; 207. Spatial coordinate mapping chip; 208. Load verification chip; 209. 3D reconstruction and communication chip; 2010. Magnetic patch; 3. Power supply and heat dissipation components; 301. Power management chip; 302. Energy storage power supply module; 303. Miniature cooling fan. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Those skilled in the art will understand that the term "comprising" as used in this application means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when we say an element is "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements present. Furthermore, "connected" or "coupled" as used herein can include wireless connections or wireless coupling. The term "and / or" as used herein includes all or any unit and all combinations of one or more associated listed items.

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] like Figures 1 to 5 As shown, this embodiment of the invention provides a three-dimensional stress monitoring device based on a flexible sensor array, comprising: The mechanical loading and clamping assembly 1 has an internal cavity for placing the specimen. The top of the mechanical loading and clamping assembly 1 is slidably provided with an upper loading bearing plate 104 in the vertical direction for applying longitudinal load to the specimen. The side of the mechanical loading and clamping assembly 1 is provided with a guide push rod 107. A flexible sensor array 111 is provided at the end of the guide push rod 107 near the specimen. The guide push rod 107 is used to fit the flexible sensor array 111 with the specimen. The flexible sensor array 111 is used to collect the mechanical response signal of the specimen. The sensing acquisition and 3D reconstruction component 2 is located outside the mechanical loading and clamping component 1 and is electrically connected to the flexible sensor array 111, and is used to reconstruct the 3D stress transmission response field.

[0023] In this embodiment, the mechanical loading and clamping assembly 1 includes: A bottom support plate 101 is provided, and a top support plate 102 is arranged at intervals above it; A lateral support plate 103 is disposed between a bottom support plate 101 and a top support plate 102, and is connected and fixed to the bottom support plate 101 and the top support plate 102 respectively by fixing screws 112. The bottom support plate 101, the top support plate 102 and the lateral support plate 103 form a receiving cavity. A sealed sliding bearing 113 is provided on the top support plate 102, and the upper loading pressure plate 104 is slidably connected to the sealed sliding bearing 113. A threaded hole is provided on the lateral support plate 103, and the tail end of the guide push rod 107 is connected to the threaded adjusting rod 106. The threaded adjusting rod 106 is connected to the threaded hole. The sensing acquisition and three-dimensional reconstruction component 2 is disposed on the outside of the lateral support plate 103. The lower pressure plate 105 is disposed in the receiving cavity and located on the bottom support plate 101; The lateral force transmission pressure plate 109 is connected to the front end of the guide push rod 107. The lateral force transmission pressure plate 109 is embedded in the flexible bonding pad 110. The flexible sensor array 111 is disposed on the side of the flexible bonding pad 110 close to the specimen.

[0024] In this embodiment, a positioning structure can be provided on the flexible bonding pad 110 to facilitate the installation and positioning of the flexible sensor array 111. A screw-limiting structure is provided at the end of the threaded adjusting rod 106 away from the test piece.

[0025] In this embodiment, the lateral support plate 103 is a detachable structure. Multiple lateral support plates 103 can be selected and installed between the bottom support plate 101 and the top support plate 102 according to the shape of the specimen, the loading method, or the monitoring position, forming a single-sided, double-sided, three-sided, or four-sided enclosed installation structure. The lateral force transmission plate 109 is a replaceable structure. The side of the lateral force transmission plate 109 closest to the specimen is set as a mating surface adapted to the outer surface of the specimen. The mating surface is one of a plane, an arc surface, or an irregularly shaped mating surface to match cubic specimens, cuboid specimens, cylindrical specimens, or irregularly shaped specimens.

[0026] In this embodiment, the sensing acquisition and 3D reconstruction component 2 includes: The monitoring sensor integration box 201 is located on the outside of the lateral support plate 103. The monitoring sensor integration box 201 contains: a flexible sensor access chip 202, a signal conditioning chip 203, a multi-channel synchronous acquisition chip 204, a load displacement synchronous access chip 205, a pre-tightening baseline correction chip 206, a spatial coordinate mapping chip 207, a load verification chip 208, and a three-dimensional reconstruction and communication chip 209. The flexible sensor access chip 202 is electrically connected to the flexible sensor array 111. The signal conditioning chip 203 is electrically connected to the flexible sensor access chip 202. The multi-channel synchronous acquisition chip 204 is electrically connected to the signal conditioning chip 203 and the load displacement synchronous access chip 205, respectively. The pre-tightening baseline correction chip 206, the spatial coordinate mapping chip 207, and the load verification chip 208 are electrically connected to the multi-channel synchronous acquisition chip 204, respectively. The three-dimensional reconstruction and communication chip 209 is electrically connected to the pre-tightening baseline correction chip 206, the spatial coordinate mapping chip 207, and the load verification chip 208, respectively.

[0027] In this embodiment, a power supply and heat dissipation component 3 is also included. The power supply and heat dissipation component 3 includes a power management chip 301, an energy storage power supply module 302, and a miniature cooling fan 303 disposed in the monitoring and sensing integration box 201. The energy storage power supply module 302 is electrically connected to the power management chip 301. The power management chip 301 is electrically connected to the flexible sensing access chip 202, the signal conditioning chip 203, the multi-channel synchronous acquisition chip 204, the load displacement synchronous access chip 205, the pre-tightening baseline correction chip 206, the spatial coordinate mapping chip 207, the load verification chip 208, the three-dimensional reconstruction and communication chip 209, and the miniature cooling fan 303. The monitoring and sensing integration box 201 has an air outlet, and the miniature cooling fan 303 is disposed at the air outlet.

[0028] In this embodiment, the monitoring sensor integration box 201 is provided with external connection openings for each chip.

[0029] In this embodiment, the monitoring sensor integration box 201 is attached to the outside of the lateral support plate 103 by magnetic patch 2010.

[0030] In this embodiment, the threaded adjusting rod 106 and / or the guide pushing rod 107 are provided with multiple adjusting connection holes. These holes are elongated structures arranged along the length of the threaded adjusting rod 106. A hinge pin 108 is inserted into each adjusting connection hole, causing the threaded adjusting rod 106 and the guide pushing rod 107 to slide together. A preload spring is provided between the threaded adjusting rod 106 and the guide pushing rod 107, and this preload spring has an elastic tendency to push the guide pushing rod 107 towards the specimen. Inserting the hinge pin 108 into different adjusting connection holes allows adjustment of the initial position of the flexible sensor array 111.

[0031] In this embodiment, the flexible sensor array 111 is detachably connected to an upper sensor array and a lower sensor array. The upper sensor array is arranged between the specimen and the upper loading pressure plate 104, and the lower sensor array is arranged between the specimen and the lower pressure plate 105.

[0032] In this embodiment, a leveling ball head is provided on the upper loading pressure plate 104, and a lateral leveling ball head is provided at one end of the guide push rod 107 near the lateral force transmission pressure plate 109, which can produce a small angle adjustment relative to the force direction.

[0033] In this embodiment, the threaded adjusting rod 106 and the guide push rod 107 are provided with wiring grooves along the axis, and the wires of the flexible sensor array 111 are led outward along the wiring grooves.

[0034] This invention also provides a three-dimensional stress reconstruction method based on a flexible sensor array, using a three-dimensional stress monitoring device based on a flexible sensor array, comprising the following steps: S1: The flexible sensor array 111 is brought into contact with the specimen by adjusting the threaded rod and the guide push rod 107. The external loading device applies a longitudinal load to the specimen through the upper loading bearing plate 104. The flexible sensor array 111 acquires the mechanical response signals of different measuring points during the loading process of the specimen and inputs the mechanical response signals to the flexible sensing access chip 202. The flexible sensing access chip 202 performs channel identification on the signals of each measuring point according to the sensing unit number, forming an original sensing data frame with the measuring point number attribute. S2: Signal conditioning chip 203 receives the original sensing data frame and amplifies, filters, suppresses zero drift, and removes abnormal pulses from each channel signal to form a conditioned sensing data frame; multi-channel synchronous acquisition chip 204 synchronously samples the conditioned sensing data frame and assigns a unified time identifier to the data of each channel at the same sampling time to form a time-synchronized sensing data frame. S3: The load displacement synchronization access chip 205 receives the load data and displacement data output by the external loading device, and matches them with the time synchronization sensing data frame according to the unified time identifier to form a load synchronization data frame containing sensing response, load information and displacement information. S4: The pre-tightening baseline correction chip 206 calls the initial pre-tightening baseline data obtained by the flexible sensor array 111 before the external loading device loads, and performs point-by-point baseline subtraction on the sensing response of each measuring point in the loading synchronization data frame to obtain the net response data frame of each measuring point relative to the initial bonding state. S5: The spatial coordinate mapping chip 207 maps the measurement point data in the net response data frame to the corresponding three-dimensional spatial coordinate position of the specimen according to the measurement point number, installation orientation and array arrangement of the flexible sensor array 111, forming a spatiotemporal mapping data frame containing time stamp, measurement point number, spatial coordinate and net response value. S6: Load verification chip 208 performs load constraint verification on the spatiotemporal mapping data frame based on the load data accessed by load displacement synchronous access chip 205; when there is a systematic deviation between the net response data of each measuring point and the overall load data, load verification chip 208 normalizes and corrects the net response value of each measuring point based on the load data to form the verified spatiotemporal mechanical response data frame. S7: The 3D reconstruction and communication chip 209 receives the verified spatiotemporal mechanical response data frame, and uses the 3D geometric model of the specimen as the reconstruction object. It takes the spatial coordinates corresponding to each measuring point as boundary or surface constraint nodes, and generates the equivalent response value of the corresponding position inside the specimen through spatial interpolation, neighborhood weighting and voxel filling, forming a 3D stress transfer response field. S8: The 3D reconstruction and communication chip 209 organizes the continuously formed 3D stress transfer response field in stages according to the loading time, load level or displacement stage, and generates 3D stress transfer evolution maps at different times or different loading stages. S9: The 3D reconstruction and communication chip 209 extracts the maximum, minimum and average values ​​from the 3D stress transfer evolution map and generates the maximum value monitoring curve in chronological order. At the same time, it outputs the 3D stress transfer evolution map, maximum, minimum, average and maximum value monitoring curve to the external display terminal.

[0035] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0036] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0037] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0038] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A three-dimensional stress monitoring device based on a flexible sensor array, characterized in that, include: A mechanical loading and clamping assembly (1) has an internal cavity for placing a specimen. The top of the mechanical loading and clamping assembly (1) is slidably provided with an upper loading bearing plate (104) in the vertical direction for applying a longitudinal load to the specimen. A guide push rod (107) is provided on the side of the mechanical loading and clamping assembly (1). A flexible sensor array (111) is provided at the end of the guide push rod (107) near the specimen. The guide push rod (107) is used to fit the flexible sensor array (111) with the specimen. The flexible sensor array (111) is used to collect the mechanical response signal of the specimen. The sensing acquisition and three-dimensional reconstruction component (2) is disposed on the outside of the mechanical loading and clamping component (1) and electrically connected to the flexible sensor array (111) for reconstructing the three-dimensional stress transmission response field.

2. The three-dimensional stress monitoring device based on a flexible sensor array according to claim 1, characterized in that, The mechanical loading and clamping assembly (1) includes: A bottom support plate (101) is provided with a top support plate (102) arranged at intervals above it. A lateral support plate (103) is disposed between the bottom support plate (101) and the top support plate (102), and the bottom support plate (101), the top support plate (102) and the lateral support plate (103) form the receiving cavity; a sealed sliding bearing (113) is disposed on the top support plate (102), and the upper loading pressure plate (104) is slidably connected to the sealed sliding bearing (113); a threaded hole is provided on the lateral support plate (103), and the tail end of the guide push rod (107) is connected to the threaded adjusting rod (106), and the threaded adjusting rod (106) is engaged with the threaded hole; the sensing acquisition and three-dimensional reconstruction component (2) is disposed on the outside of the lateral support plate (103); The lower pressure plate (105) is disposed in the receiving cavity and located on the bottom support plate (101); Lateral force transmission pressure plate (109), the front end of the guide push rod (107) is connected to the lateral force transmission pressure plate (109), the lateral force transmission pressure plate (109) is embedded in the flexible bonding pad (110), and the flexible sensor array (111) is disposed on the side of the flexible bonding pad (110) close to the specimen.

3. The three-dimensional stress monitoring device based on a flexible sensor array according to claim 2, characterized in that, The sensing acquisition and 3D reconstruction component (2) includes: A monitoring sensor integration box (201) is disposed on the outside of the lateral support plate (103). The monitoring sensor integration box (201) contains: a flexible sensor access chip (202), a signal conditioning chip (203), a multi-channel synchronous acquisition chip (204), a load displacement synchronous access chip (205), a pre-tightening baseline correction chip (206), a spatial coordinate mapping chip (207), a load verification chip (208), and a three-dimensional reconstruction and communication chip (209). The flexible sensor access chip (202) is electrically connected to the flexible sensor array (111). The signal conditioning chip... The chip (203) is electrically connected to the flexible sensing access chip (202). The multi-channel synchronous acquisition chip (204) is electrically connected to the signal conditioning chip (203) and the load displacement synchronous access chip (205), respectively. The pre-tightening baseline correction chip (206), the spatial coordinate mapping chip (207), and the load verification chip (208) are electrically connected to the multi-channel synchronous acquisition chip (204), respectively. The three-dimensional reconstruction and communication chip (209) is electrically connected to the pre-tightening baseline correction chip (206), the spatial coordinate mapping chip (207), and the load verification chip (208), respectively.

4. The three-dimensional stress monitoring device based on a flexible sensor array according to claim 3, characterized in that, It also includes a power supply and heat dissipation assembly (3), which includes a power management chip (301), an energy storage power supply module (302), and a miniature cooling fan (303) disposed in the monitoring and sensing integration box (201); the energy storage power supply module (302) is electrically connected to the power management chip (301), and the power management chip (301) is electrically connected to the flexible sensing access chip (202), the signal conditioning chip (203), the multi-channel synchronous acquisition chip (204), the load displacement synchronous access chip (205), the pre-tightening baseline correction chip (206), the spatial coordinate mapping chip (207), the load verification chip (208), the three-dimensional reconstruction and communication chip (209), and the miniature cooling fan (303); the monitoring and sensing integration box (201) has an air outlet, and the miniature cooling fan (303) is disposed at the air outlet.

5. A three-dimensional stress monitoring device based on a flexible sensor array according to claim 4, characterized in that, The monitoring sensor integration box (201) is attached to the outside of the lateral support plate (103) by a magnetic patch (2010).

6. A three-dimensional stress monitoring device based on a flexible sensor array according to claim 4, characterized in that, The threaded adjusting rod (106) and / or the guide pushing rod (107) are provided with a plurality of adjusting connection holes. The adjusting connection holes are elongated hole structures arranged along the length direction of the threaded adjusting rod (106). A hinge pin (108) is inserted into the adjusting connection hole to make the threaded adjusting rod (106) and the guide pushing rod (107) slide together. A preload spring is provided between the threaded adjusting rod (106) and the guide pushing rod (107). The preload spring has an elastic tendency to push the guide pushing rod (107) toward the specimen.

7. A three-dimensional stress monitoring device based on a flexible sensor array according to claim 4, characterized in that, The flexible sensor array (111) is detachably connected to an upper sensor array and a lower sensor array. The upper sensor array is arranged between the specimen and the upper loading pressure plate (104), and the lower sensor array is arranged between the specimen and the lower pressure plate (105).

8. A three-dimensional stress monitoring device based on a flexible sensor array according to claim 4, characterized in that, The upper loading pressure plate (104) is provided with a leveling ball head, and the guide push rod (107) is provided with a lateral leveling ball head at one end near the lateral force transmission pressure plate (109).

9. A three-dimensional stress monitoring device based on a flexible sensor array according to claim 4, characterized in that, The threaded adjusting rod (106) and the guide push rod (107) are provided with wiring grooves along the axis, and the wires of the flexible sensor array (111) are led outward along the wiring grooves.

10. A three-dimensional stress reconstruction method based on a flexible sensor array, characterized in that, The three-dimensional stress monitoring device based on a flexible sensor array according to any one of claims 4-9 includes the following steps: S1: The flexible sensor array (111) is attached to the specimen by adjusting the threaded rod and the guide push rod (107). The external loading device applies a longitudinal load to the specimen through the upper loading bearing plate (104). The flexible sensor array (111) acquires the mechanical response signals of different measuring points during the loading process of the specimen and inputs the mechanical response signals to the flexible sensing access chip (202). The flexible sensing access chip (202) performs channel identification on the signals of each measuring point according to the sensing unit number to form an original sensing data frame with the measuring point number attribute. S2: The signal conditioning chip (203) receives the original sensing data frame and amplifies, filters, suppresses zero drift and removes abnormal pulses for each channel signal to form a conditioned sensing data frame; the multi-channel synchronous acquisition chip (204) synchronously samples the conditioned sensing data frame and assigns a unified time identifier to the data of each channel at the same sampling time to form a time-synchronized sensing data frame. S3: The load displacement synchronization access chip (205) receives the load data and displacement data output by the external loading device, and matches them with the time synchronization sensing data frame according to the unified time identifier to form a load synchronization data frame containing sensing response, load information and displacement information. S4: The pre-tightening baseline correction chip (206) calls the initial pre-tightening baseline data obtained by the flexible sensor array (111) before the external loading device loads, and performs point-by-point baseline subtraction on the sensing response of each measuring point in the loading synchronization data frame to obtain the net response data frame of each measuring point relative to the initial bonding state. S5: The spatial coordinate mapping chip (207) maps the measurement point data in the net response data frame to the three-dimensional spatial coordinate position corresponding to the specimen according to the measurement point number, installation orientation and array arrangement of the flexible sensor array (111), forming a spatiotemporal mapping data frame containing time marker, measurement point number, spatial coordinate and net response value. S6: The load verification chip (208) performs load constraint verification on the spatiotemporal mapping data frame based on the load data accessed by the load displacement synchronization access chip (205); when there is a systematic deviation between the net response data of each measuring point and the overall load data, the load verification chip (208) normalizes and corrects the net response value of each measuring point based on the load data to form the verified spatiotemporal mechanical response data frame. S7: The three-dimensional reconstruction and communication chip (209) receives the verified spatiotemporal mechanical response data frame, and takes the three-dimensional geometric model of the specimen as the reconstruction object. It uses the spatial coordinates corresponding to each measuring point as boundary or surface constraint nodes, and generates the equivalent response value of the corresponding position inside the specimen through spatial interpolation, neighborhood weighting and voxel filling, forming a three-dimensional stress transfer response field. S8: The three-dimensional reconstruction and communication chip (209) organizes the continuously formed three-dimensional stress transmission response field in stages according to the loading time, load level or displacement stage, and generates three-dimensional stress transmission evolution maps at different times or different loading stages. S9: The three-dimensional reconstruction and communication chip (209) extracts the maximum value, minimum value and average value from the three-dimensional stress transmission evolution map, and generates the maximum value monitoring curve in chronological order. At the same time, it outputs the three-dimensional stress transmission evolution map, maximum value, minimum value, average value and maximum value monitoring curve to the external display terminal.

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