CN114782658A - Structure test monitoring and early warning system and method based on digital twinning and augmented reality - Google Patents
Structure test monitoring and early warning system and method based on digital twinning and augmented reality Download PDFInfo
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- CN114782658A CN114782658A CN202210412427.7A CN202210412427A CN114782658A CN 114782658 A CN114782658 A CN 114782658A CN 202210412427 A CN202210412427 A CN 202210412427A CN 114782658 A CN114782658 A CN 114782658A
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Abstract
The invention discloses a structural test monitoring and early warning system and method based on digital twins and augmented reality. The invention adopts a machine vision system and augmented reality glasses to cooperatively complete the augmented reality coordinate construction and the test piece pose contour estimation in the simultaneous movement of an observer and a test piece, adopts a test monitoring system and a digital twin system to combine and analyze the full-field response and the potential failure area of the test piece in real time, fuses a real scene, numerical analysis and test data through an augmented reality server, and completes the superposition of the data and the real scene through the augmented reality glasses to realize man-machine interaction, thereby having important significance for assisting a tester to monitor and early warn the large-scale structural test process, improving the test efficiency and safety and visually understanding the test process and phenomena.
Description
Technical Field
The invention relates to a system and a method for full-field monitoring and early warning of a structure, in particular to a system and a method for monitoring a large-scale structure test process and early warning of test operation based on digital twins and augmented reality.
Background
In the fields of aerospace rail traffic and the like, in order to verify the reliability of structural product design, mechanical tests or thermal assessment tests of structures are often required to be carried out, such as carrying out full-size static tests on airplane wings, carrying out thermal combination tests on high-speed aircraft cabins, carrying out thermal assessment tests on thermal protection structures and the like. However, the test of large-scale structural products is often very difficult, and relates to a large amount of loading designs, multi-load linkage and the like, the test preparation period is long, and the product cost is high. Especially for new product design, due to insufficient cognition on structural characteristics, on one hand, unexpected failure may occur in the test, so that structural products and test equipment are lost, and on the other hand, some key test phenomena may be neglected in the test process. Therefore, there is a great need to enhance the real-time and comprehensive monitoring of the testing process of large structural products.
In the past, in the structural test monitoring, a tester needs to monitor the readings of a plurality of instruments and meters and sensors at the same time, because a plurality of information needs to be tracked and the corresponding relation between the information and a test piece needs to be judged, the mode essentially faces larger hysteresis, and due to the limitation of the number of the sensors, the comprehensive monitoring of the test process is difficult to realize. These not only can bring the test procedure security hidden danger, and the tester lacks the intuitional understanding of test procedure moreover, and follow-up experimental analysis has the difficulty. Currently, the augmented reality technology is applied to monitoring the operation state of various mechanical devices and used for scenes such as operation early warning and auxiliary maintenance. Different from the application, the method adopts augmented reality for monitoring and early warning in the structural test, and comprises the following steps: 1) virtual and real scenes are difficult to superpose, a large amount of scene change is caused by changing test objects and loading modes in the test, virtual scene superposition objects, namely structural test pieces, are greatly deformed, and testers, namely observers, frequently move and the like; 2) a few measuring points arranged on the structure cannot provide full-field information of the test piece, especially some potential failure areas which are not considered in advance can be ignored, and the potential failure areas cannot be directly used for full-field monitoring and early warning of the structure.
Disclosure of Invention
The invention aims to provide a structural test monitoring and early warning system and method based on digital twinning and augmented reality, which can provide virtual and real combined test process and full-field response information of a test piece for a tester in the test process of a structural product, and assist in monitoring and early warning of the test process.
The purpose of the invention is realized by the following technical scheme:
the utility model provides a structural test monitoring early warning system based on digital twin and augmented reality, includes machine vision system, experimental control system, digital twin analog system, augmented reality server, augmented reality glasses, wherein:
the machine vision system is used for completing image acquisition of a real test scene and a test structural part;
the test control system is used for completing test load loading and sensor data acquisition installed on a test piece;
the digital twin simulation module is used for acquiring test load and sensor data from the test control system and completing on-line simulation of structural response of a test piece to be tested under the test load;
the augmented reality server is used for integrating data from a machine vision system, a test control system and a digital twinning simulation system, constructing real scene coordinates and a test piece deformed model, and overlapping the test piece model and test piece response data to construct a virtual scene;
the augmented reality glasses are used for acquiring data from the augmented reality server, finishing scene rendering and outputting images and finishing man-machine interaction.
A structure test monitoring and early warning method based on digital twins and augmented reality by adopting the system comprises the following steps:
step 1) acquiring an image of a real test scene through a machine vision system, measuring a deformed outline of a test structural part in a test process and transmitting the deformed outline to an augmented reality server, and constructing a coordinate corresponding to the real test scene and a test structural part outline coordinate by the augmented reality server;
step 2) loading a test structural member through a test control system, synchronously acquiring sensor data in the test process, driving a digital twin system to perform online simulation calculation, acquiring full-field temperature, deformation, stress and strain response data in the test structural member test process, and marking a hot spot area of the test member according to a damage criterion;
step 3) receiving load and sensor data transmitted by a test control system, full-field strain and stress response data transmitted by a digital twin system and hot spot area information of a test structural member through an augmented reality server, superposing the data on the surface of the deformed test structural member and constructing a virtual scene;
step 4) the tester adopts the augmented reality glasses to observe the test structural part, the augmented reality glasses acquire the image of a real test scene at the background and establish the coordinates of an observer in real time, the augmented reality glasses send coordinate information and data requirements to the augmented reality server, and the augmented reality server performs imaging rendering according to the data returned by the augmented reality server and superimposes the data on the surface of the real test structural part in a display screen;
and 5) carrying out test state monitoring and early warning by testers according to the virtual and real synchronous information.
In the invention, a machine vision system and augmented reality glasses are adopted to cooperatively complete the construction of augmented reality coordinates and the estimation of the pose and form of a test piece in the simultaneous movement of an observer and a test structural piece, wherein the machine vision system is positioned at a fixed position and is used for completing the construction of coordinates of a test area and the measurement of the outline of the test structural piece, and the augmented reality glasses are used for establishing the establishment of coordinates in the moving process of the observer.
In the invention, the digital twin system executes simulation based on a physical mechanism, reconstructs full-field response of a test structural part to enhance sensor discrete data acquired by the test control system, and testers can set failure criteria of the test structural part to realize real-time analysis and marking of a hot spot area and assist the testers in carrying out test visual early warning.
Compared with the prior art, the invention has the following advantages:
the invention adopts a machine vision system and augmented reality glasses to cooperatively complete the augmented reality coordinate construction and the pose profile estimation of a test piece during the simultaneous movement of an observer and the test piece, adopts a test monitoring system and a digital twin system to combine to analyze the full-field response and the potential failure area of the test piece in real time, fuses a real scene, numerical analysis and test data through an augmented reality server, and completes the superposition of the data and the real scene through the augmented reality glasses to realize man-machine interaction, thereby having important significance for assisting a tester to monitor and early warn the test process of a large-scale structure, improving the test efficiency and safety and visually understanding the test process and phenomena.
Drawings
Fig. 1 is a schematic structural diagram of a structural test monitoring and early warning system based on digital twins and augmented reality, in which: the system comprises a machine vision system, a test control system, a digital twinborn simulation system, an augmented reality server and augmented reality glasses.
Detailed Description
The technical solutions of the present invention are further described below with reference to the drawings, but the present invention is not limited thereto, and any modifications or equivalent substitutions may be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.
The invention provides a structural test monitoring and early warning system based on digital twins and augmented reality, as shown in figure 1, the system consists of 5 subsystems of a machine vision system, a test control system, a digital twins simulation system, an augmented reality server and augmented reality glasses, the subsystems are integrated into a whole system, wherein:
the machine vision system is used for completing image acquisition of a real test scene and a test structural member;
the test control system is used for completing test load loading and sensor data acquisition installed on a test piece;
the digital twin simulation module is used for acquiring test load and sensor data from the test control system and completing on-line simulation of structural response of a test piece to be tested under the test load;
the augmented reality server is used for integrating data from a machine vision system, a test control system and a digital twin simulation system, constructing real scene coordinates and a model of a test piece after deformation, and overlapping the test piece model and test piece response data to construct a virtual scene;
the augmented reality glasses are used for acquiring data from the augmented reality server, finishing scene rendering and outputting images and finishing man-machine interaction.
In the invention, the machine vision system is arranged at a fixed position, and 2 functions are completed through multi-view image acquisition and image identification on a test structural member, namely: and finishing image acquisition of a test area and a test structural member through 2 cameras, and carrying out coordinate identification of the test area and pose profile measurement after deformation of the test structural member.
In the invention, the digital twin simulation system runs on a high-performance computing platform, and establishes bidirectional data connection with a test control system and an augmented reality server by adopting ANSYS Discovery Live software and interface development.
In the invention, the digital twin simulation system utilizes the load and sensor data given by the test control system, runs the simulation of the test process while the test is carried out, calculates the full-field temperature, deformation, stress and strain response data of the test structural member in real time, realizes the real-time analysis and marking of the potential failure hot spot area of the test structural member, and transmits the data to the augmented reality server, wherein: the simulation adopts a model corresponding to test conditions and based on a physical mechanism, combines sensor data given by a test control system to check the model in real time, adopts the checked data to calculate full-field temperature, deformation, stress and strain response data of a test structural part in real time, and reconstructs the full-field response of the test structural part to enhance the sensor discrete data acquired by the test control system.
In the invention, the augmented reality server is a real scene and data integration and processing unit, adopts Vuforia to construct an augmented reality application program of a test system, is used for receiving the 3D contour coordinates of a deformed test structural part given by a machine vision system, receiving sensor data transmitted by a test control system and structural temperature, deformation, stress and strain response data calculated and given by a digital twinning simulation system, integrating the data with the 3D contour of the deformed test structural part to construct a virtual scene, transforming the virtual scene to the coordinates of an observer according to the demand instruction of augmented reality glasses, and transmitting the coordinates to the augmented reality glasses through a wireless network.
In the invention, the augmented reality glasses adopt the camera carried by the augmented reality glasses to acquire real scene image information, set up observer coordinates according to a camera angle and a test area identifier, read test structural part response information provided by an augmented reality server, perform imaging rendering, and superimpose the information on the surface of a deformed test structural part in a display screen, thereby assisting a tester to perform test visual early warning.
A structure test monitoring and early warning method based on digital twins and augmented reality by adopting the system comprises the following steps:
step 1) acquiring an image of a real test scene through a machine vision system, measuring a deformed outline of the test structural member in a test process through image characteristics such as speckles and light spots on the test structural member, and transmitting the outline to an augmented reality server, wherein the augmented reality server constructs a coordinate corresponding to the real test scene and a coordinate of the outline of the test structural member;
step 2) introducing a geometric model and a material constitutive model of a test structural part into a digital twinborn simulation system, setting boundary conditions consistent with test loads, setting Mises strength criteria for a metal structure, setting Tsai-Hill criteria for a composite material structure, setting phenomenological criteria determined by tests for other complex materials, setting highest temperature criteria for a heat-proof material, simulating the test process by adopting a finite element technology, loading the test structural part through a test control system, synchronously acquiring sensor data in the test process, driving the digital twinborn system to perform online simulation calculation, comparing simulation results of the same position given by a simulation model with the deformation and local strain sensor measurement results of the test structural part given by the test control system, and adjusting material parameters in the digital twinborn simulation system through an optimization method to enable the simulation results to be consistent with the tests, and acquiring full-field temperature, deformation, stress and strain response data of the test structural part in the test process by using the corrected model, marking a hot spot area of the test structural part according to a damage criterion, extracting full-field response information and corresponding coordinate data of the surface of the test structural part, and transmitting the full-field response information and the corresponding coordinate data to the augmented reality server.
And 3) receiving load and sensor data transmitted by the test control system, full-field strain and stress response data transmitted by the digital twin system and hot spot area information of the test structural member through the augmented reality server, constructing corresponding relations between simulation data, test data and real test structural member coordinates, and constructing a virtual scene.
And step 4) the tester adopts the augmented reality glasses to observe the test structural part, the augmented reality glasses acquire the image of the real test scene at the background and establish the coordinates of the observer in real time, the coordinate information and the data requirement are sent to the augmented reality server, imaging rendering is carried out according to the data returned by the augmented reality server, and the data are overlaid on the surface of the real test structural part in the display screen.
And 5) carrying out test state monitoring and early warning by testers according to the virtual and real synchronous information.
Claims (7)
1. The utility model provides a structure test monitoring and early warning system based on digital twin and augmented reality, its characterized in that structure test monitoring and early warning system includes machine vision system, experimental control system, digital twin analog system, augmented reality server, augmented reality glasses, wherein:
the machine vision system is used for completing image acquisition of a real test scene and a test structural part;
the test control system is used for completing test load loading and sensor data acquisition installed on a test piece;
the digital twin simulation module is used for acquiring test load and sensor data from the test control system and completing on-line simulation of structural response of a test piece to be tested under the test load;
the augmented reality server is used for integrating data from a machine vision system, a test control system and a digital twin simulation system, constructing real scene coordinates and a model of a test piece after deformation, and overlapping the test piece model and test piece response data to construct a virtual scene;
the augmented reality glasses are used for acquiring data from the augmented reality server, finishing scene rendering and outputting images and finishing man-machine interaction.
2. The structural test monitoring and early warning system based on digital twins and augmented reality as claimed in claim 1, wherein the machine vision system is mounted at a fixed position, and image acquisition of a test region and a test structural member is completed through 2 cameras to perform coordinate identification of the test region and pose profile measurement after deformation of the test structural member.
3. The structural test monitoring and early warning system based on digital twins and augmented reality as claimed in claim 1, wherein the digital twins simulation system utilizes load and sensor data given by the test control system, runs simulation of a test process while a test is carried out, calculates full-field temperature, deformation, stress and strain response data of a test structural member in real time, realizes real-time analysis and marking of a potential failure hot spot region of the test structural member, and transmits the data to the augmented reality server.
4. The structural test monitoring and early warning system based on digital twins and augmented reality as claimed in claim 3, wherein the simulation adopts a model corresponding to test conditions and based on a physical mechanism, the model is verified in real time by combining sensor data given by a test control system, full-field temperature, deformation, stress and strain response data of a test structural part are calculated in real time by using the verified data, and the full-field response of the test structural part is reconstructed to enhance the sensor discrete data acquired by the test control system.
5. The structural test monitoring and early warning system based on digital twins and augmented reality as claimed in claim 1, wherein the augmented reality server is a real scene and data integration and processing unit, an augmented reality application program of the test system is constructed by adopting Vuforia, and the system is used for receiving the 3D contour coordinates of the test structural member after deformation given by the machine vision system, receiving sensor data transmitted by the test control system and structural temperature, deformation, stress and strain response data calculated and given by the digital twins simulation system, integrating the data and the 3D contour of the test structural member after deformation, constructing a virtual scene, transforming the virtual scene to the coordinates of an observer according to the demand instruction of the augmented reality glasses, and transmitting the virtual scene to the augmented reality glasses through a wireless network.
6. The structural test monitoring and early warning system based on digital twins and augmented reality as claimed in claim 1, wherein the augmented reality glasses adopt a camera carried by the glasses to acquire real scene image information, establish observer coordinates according to a camera angle and a test area identifier, read test structural part response information provided by the augmented reality server and perform imaging rendering, and superimpose the test structural part response information on the surface of the deformed test structural part in a display screen, thereby assisting a tester in performing test visual early warning.
7. A method for realizing digital twinning and augmented reality-based structural test monitoring and early warning by adopting the structural test monitoring and early warning system as claimed in any one of claims 1 to 6, which is characterized by comprising the following steps:
step 1) acquiring an image of a real test scene through a machine vision system, measuring a deformed outline of a test structural part in a test process and transmitting the deformed outline to an augmented reality server, and constructing a coordinate corresponding to the real test scene and a test structural part outline coordinate by the augmented reality server;
step 2) loading a test structural member through a test control system, synchronously acquiring sensor data in the test process, driving a digital twin system to perform online simulation calculation, acquiring full-field temperature, deformation, stress and strain response data in the test structural member test process, and marking a hot spot area of the test member according to a damage criterion;
step 3) receiving load and sensor data transmitted by the test control system, full-field strain and stress response data transmitted by the digital twin system and hot spot area information of the test structural member through the augmented reality server, superposing the data on the surface of the deformed test structural member and constructing a virtual scene;
step 4) the tester adopts the augmented reality glasses to observe the test structural part, the augmented reality glasses acquire the image of a real test scene at the background and establish the coordinates of an observer in real time, the augmented reality glasses send coordinate information and data requirements to the augmented reality server, and the augmented reality server performs imaging rendering according to the data returned by the augmented reality server and superimposes the data on the surface of the real test structural part in a display screen;
and 5) carrying out test state monitoring and early warning by testers according to the virtual and real synchronous information.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115130049A (en) * | 2022-09-02 | 2022-09-30 | 中国飞机强度研究所 | Risk control system for aircraft complete machine level high-temperature test and construction method thereof |
| CN117763926A (en) * | 2024-02-22 | 2024-03-26 | 大连理工大学 | digital twin information driven high-reliability structure deformation monitoring method |
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2022
- 2022-04-19 CN CN202210412427.7A patent/CN114782658A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115130049A (en) * | 2022-09-02 | 2022-09-30 | 中国飞机强度研究所 | Risk control system for aircraft complete machine level high-temperature test and construction method thereof |
| CN115130049B (en) * | 2022-09-02 | 2022-11-25 | 中国飞机强度研究所 | Risk control system for aircraft complete machine level high-temperature test and construction method thereof |
| CN117763926A (en) * | 2024-02-22 | 2024-03-26 | 大连理工大学 | digital twin information driven high-reliability structure deformation monitoring method |
| CN117763926B (en) * | 2024-02-22 | 2024-05-17 | 大连理工大学 | Digital twin information driven high-reliability structure deformation monitoring method |
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