Multi-view feature-based motor imagery classification method and device, equipment and storage medium
By adopting a U-shaped ferrite yoke with adjustable span and a high-sensitivity TMR sensor in the ACFM detection system, combined with accurate signal excitation and processing technology, the signal sensitivity and accuracy problems in the detection of thick-coated metal components are solved, and the detection effect of high accuracy and flexibility is achieved.
Patent Information
- Application Number
- CN202411831829.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-12
- Publication Date
- 2025-03-28
AI Technical Summary
The existing AC electromagnetic field detection (ACFM) technology is significantly affected when detecting thick-coated metal components, making it difficult to meet the needs of high sensitivity and high accuracy in key areas such as offshore oil drilling platforms and spacecraft.
It adopts a U-shaped ferrite yoke with adjustable span, a detection probe with a built-in TMR sensor, a signal excitation and conditioning module and a visual processing module. By accurately controlling the yoke span and excitation frequency, combining high-sensitivity TMR sensors and accurate signal acquisition and processing technology, weak defect signals are captured and identified.
It improves the high accuracy of the detection results, enhances the applicability and flexibility of the system, and can effectively deal with the complexity of detection under thick coating conditions, meeting the high sensitivity and high accuracy requirements in industrial applications.
Smart Images
Figure CN119715773A_ABST
Abstract
Description
Technical Field
[0001] The present application belongs to the field of motion recognition technology, and in particular, relates to a method, device, equipment and storage medium for classifying motion imagery based on multi-view features. Background Art
[0002] In the field of nondestructive testing, ACFM technology is widely used due to its high detection sensitivity for surface and near-surface defects of metal materials. This technology generates an alternating magnetic field through the excitation coil, which interacts with the metal workpiece to stimulate eddy currents and generate secondary magnetic fields. By detecting changes in these magnetic fields, defects can be located and evaluated. However, in practical applications, especially when facing metal components with thick coatings, the detection performance of ACFM technology will be significantly affected.
[0003] In traditional ACFM detection systems, the design of the magnetic circuit is crucial to the strength and stability of the detection signal. The magnetic circuit is mainly composed of an excitation coil and a magnetic yoke, and its design needs to consider factors such as magnetic permeability, electrical conductivity, and geometric dimensions. However, when faced with metal components with thick coatings, since the magnetic permeability and electrical conductivity of the coating material may be different from those of the metal being detected, the propagation of the electromagnetic field in the coating is hindered, thereby reducing the sensitivity of the detection signal. In addition, the thick coating will also increase the distance between the probe and the workpiece, that is, the lift-off height, causing the magnetic field strength to decay rapidly according to the inverse square law, further weakening the detection signal and resulting in inaccurate detection.
[0004] Skin effect is another factor that affects the performance of ACFM under thick coating conditions. As the frequency increases, the skin depth decreases, and the electromagnetic field tends to be more concentrated on the surface of the workpiece, resulting in reduced penetration of the electromagnetic field under thick coating conditions. In addition, the presence of thick coatings may also lead to uneven distribution of the electromagnetic field, further affecting the stability and accuracy of the detection signal.
[0005] In key areas such as offshore oil drilling platforms, submarine oil pipelines, and spacecraft, the reliability of metal components is crucial to ensuring industrial safety and operational efficiency. These components are usually covered with thick anti-corrosion or thermal insulation coatings to resist seawater corrosion, microbial attachment, ultraviolet radiation, or high temperature conduction. However, the presence of these coatings greatly increases the difficulty of crack defect detection, making it difficult for traditional detection methods to meet the requirements of high sensitivity and high accuracy in industrial applications.
[0006] Therefore, existing ACFM systems often require complex equipment adjustments and extensive experimental verification when dealing with thick coatings, and their effectiveness in practical applications is limited. These challenges limit the application of ACFM technology in the inspection of thick-coated metal components, especially in key areas such as offshore oil drilling platforms, submarine oil pipelines, and aerospace vehicles, where the reliability of these components is crucial to ensuring industrial safety and operational efficiency. Summary of the invention
[0007] The embodiment of the present application provides a detection system for ACFM detection of thick coatings, the system comprising: a U-shaped ferrite yoke with adjustable span, a detection probe with a built-in TMR sensor, a signal excitation and conditioning module, and a visualization processing module;
[0008] Among them, the signal excitation and conditioning module is used to control the excitation frequency of the U-shaped ferrite yoke during the detection process, the U-shaped ferrite yoke is used to provide a magnetic field that meets the preset magnetic field strength conditions for the workpiece to be tested, the detection probe with a built-in TMR sensor is used to detect the magnetic field change data of the workpiece to be tested under the action of the U-shaped ferrite yoke, and the visualization processing module is used to receive the magnetic field change data detected by the detection probe and visualize the magnetic field change data.
[0009] Optionally, the span of the U-shaped ferrite yoke is determined according to the coating thickness of the workpiece to be measured, so that the intensity of the magnetic field passing through the workpiece to be measured satisfies the preset magnetic field intensity condition.
[0010] Optionally, the detection probe with a built-in TMR sensor is arranged between two sides of the U-shaped ferrite yoke and contacts the test surface of the workpiece to be tested.
[0011] Optionally, the visualization processing module receives the magnetic field change data detected by the detection probe through an AD acquisition function of an STM32 chip.
[0012] Optionally, the visualization processing module visualizes the magnetic field change data through Visual Studio software.
[0013] Optionally, when the coating thickness of the workpiece to be tested is 10 mm, the signal excitation and conditioning module is used to control the excitation frequency of the U-shaped ferrite yoke during the detection process to a detection frequency of 5 KHz, and the yoke span of the U-shaped ferrite yoke is 30 mm.
[0014] On the other hand, the present application provides a detection method for ACFM detection of thick coatings, the method comprising:
[0015] Obtaining the coating thickness of the workpiece to be measured, and determining the yoke span and excitation frequency of the U-shaped ferrite yoke when a preset magnetic field strength condition is satisfied by using a finite element method according to the coating thickness;
[0016] The U-shaped ferrite yoke is controlled to detect the workpiece to be tested according to the yoke span and the excitation frequency through the signal excitation and conditioning module, and the magnetic field change data of the workpiece to be tested under the action of the U-shaped ferrite yoke is detected through a detection probe with a built-in TMR sensor;
[0017] The magnetic field change data is visualized through a visualization processing module.
[0018] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:
[0019] Through the U-shaped ferrite yoke with adjustable span, the detection probe with built-in TMR sensor, the signal excitation and conditioning module and the visualization processing module, that is, the use of high-sensitivity, low-noise TMR sensor and precise signal acquisition and processing technology, it is possible to effectively capture and identify weak defect signals, ensuring the high accuracy of the detection results. The adjustable design of the U-shaped ferrite yoke enables the system to be optimized for different detection conditions, improving the applicability and flexibility of the system. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0021] Figure 1 It is a structural schematic diagram of a detection system for ACFM detection of thick coatings provided by an embodiment of the present application;
[0022] Figure 2 It is a flow chart of a detection method for thick coating ACFM detection provided by an embodiment of the present application;
[0023] Figure 3 It is a detection flow chart of a detection method for thick coating ACFM detection provided by another embodiment of the present application. DETAILED DESCRIPTION
[0024] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.
[0025] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof.
[0026] It should also be understood that the term “and / or” used in the specification and appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.
[0027] As used in the specification and appended claims of this application, the term "if" can be interpreted as "when" or "uponce" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "uponce it is determined" or "in response to determining" or "uponce [described condition or event] is detected" or "in response to detecting [described condition or event]", depending on the context.
[0028] In addition, in the description of the present application specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.
[0029] References to "one embodiment" or "some embodiments" etc. described in the specification of this application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.
[0030] like Figure 1As shown, the present application provides a detection system for thick coating ACFM detection, the system comprising: a U-shaped ferrite yoke with adjustable span, a detection probe with a built-in TMR sensor, a signal excitation and conditioning module, and a visualization processing module;
[0031] Among them, the signal excitation and conditioning module is used to control the excitation frequency of the U-shaped ferrite yoke during the detection process, the U-shaped ferrite yoke is used to provide a magnetic field that meets the preset magnetic field strength conditions for the workpiece to be tested, the detection probe with a built-in TMR sensor is used to detect the magnetic field change data of the workpiece to be tested under the action of the U-shaped ferrite yoke, and the visualization processing module is used to receive the magnetic field change data detected by the detection probe and visualize the magnetic field change data.
[0032] The use of high-sensitivity, low-noise TMR sensors and precise signal acquisition and processing technology can effectively capture and identify weak defect signals, ensuring the high accuracy of the detection results. The adjustable design of the U-shaped ferrite yoke enables the system to be optimized for different detection conditions, improving the applicability and flexibility of the system.
[0033] Specifically, Figure 2 As shown, the signal excitation and conditioning module includes components such as a power amplifier, a subtractor, a phase-locked amplifier and a filter, which are used to generate and adjust the excitation signal and process the signal received from the probe. The AD acquisition function of the STM32 chip receives the magnetic field change data detected by the detection probe, and then the host computer software (VisualStudio software) realizes data visualization. At the same time, the host computer software sends out an excitation frequency, and the signal excitation and conditioning module is used to control the excitation frequency of the U-shaped ferrite yoke during the detection process.
[0034] In a possible implementation manner, the span of the U-shaped ferrite yoke is determined according to the coating thickness of the workpiece to be measured, so that the strength of the magnetic field passing through the workpiece to be measured satisfies the preset magnetic field strength condition.
[0035] In a possible implementation manner, the detection probe with a built-in TMR sensor is disposed between two sides of the U-shaped ferrite yoke and contacts the test surface of the workpiece to be tested.
[0036] In a possible implementation, the visualization processing module receives the magnetic field change data detected by the detection probe through an AD acquisition function of an STM32 chip.
[0037] In a possible implementation, the visualization processing module visualizes the magnetic field change data through Visual Studio software.
[0038] In a possible implementation, when the coating thickness of the workpiece to be tested is 10 mm, the signal excitation and conditioning module is used to control the excitation frequency of the U-shaped ferrite yoke during the detection process to a detection frequency of 5 KHz, and the yoke span of the U-shaped ferrite yoke is 30 mm.
[0039] For example, at a lift-off height of 10 mm, the best detection effect can be obtained by using a 30 mm yoke span and a detection frequency of 5 kHz. This frequency selection takes into account the influence of the skin effect on the penetration ability of the electromagnetic field, ensuring that the electromagnetic field can effectively penetrate the coating and excite eddy currents on the surface of the workpiece.
[0040] On the other hand, Figure 3 As shown, the present application provides a detection method for thick coating ACFM detection, the method comprising:
[0041] S101, obtaining a coating thickness of a workpiece to be measured, and determining a yoke span and an excitation frequency of a U-shaped ferrite yoke when a preset magnetic field strength condition is satisfied by a finite element method according to the coating thickness;
[0042] S102, controlling the U-shaped ferrite yoke to detect the workpiece to be tested according to the yoke span and the excitation frequency through a signal excitation and conditioning module, and detecting magnetic field change data of the workpiece to be tested under the action of the U-shaped ferrite yoke through a detection probe with a built-in TMR sensor;
[0043] S103: Visualize the magnetic field change data using a visualization processing module
[0044] The use of high-sensitivity, low-noise TMR sensors and precise signal acquisition and processing technology can effectively capture and identify weak defect signals, ensuring the high accuracy of the detection results. The adjustable design of the U-shaped ferrite yoke enables the system to be optimized for different detection conditions, improving the applicability and flexibility of the system.
[0045] An embodiment of the present application provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the following steps when executing the computer program: obtaining a coating thickness of a workpiece to be measured, and determining a yoke span and an excitation frequency of a U-shaped ferrite yoke when a preset magnetic field strength condition is satisfied by a finite element method according to the coating thickness; controlling the U-shaped ferrite yoke to detect the workpiece to be measured according to the yoke span and the excitation frequency through a signal excitation and conditioning module, and detecting magnetic field change data of the workpiece to be measured under the action of the U-shaped ferrite yoke through a detection probe with a built-in TMR sensor; and visualizing the magnetic field change data through a visualization processing module.
[0046] An embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the following steps are implemented: obtaining the coating thickness of the workpiece to be measured, and determining the yoke span and excitation frequency of the U-shaped ferrite yoke when a preset magnetic field strength condition is satisfied through the finite element method according to the coating thickness; controlling the U-shaped ferrite yoke to detect the workpiece to be measured according to the yoke span and the excitation frequency through a signal excitation and conditioning module, and detecting the magnetic field change data of the workpiece to be measured under the action of the U-shaped ferrite yoke through a detection probe with a built-in TMR sensor; and visualizing the magnetic field change data through a visualization processing module.
[0047] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present application implements all or part of the processes in the above-mentioned embodiment method, which can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium can at least include: any entity or device that can carry the computer program code to the camera / terminal device, recording medium, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, RandomAccess Memory), electric carrier signal, telecommunication signal and software distribution medium. For example, a USB flash drive, a mobile hard disk, a magnetic disk or an optical disk. In some jurisdictions, according to legislation and patent practice, computer-readable media cannot be electric carrier signals and telecommunication signals.
[0048] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.
[0049] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.
[0050] In the embodiments provided in the present application, it should be understood that the disclosed devices / network equipment / terminal equipment and methods can be implemented in other ways. For example, the device / network equipment / terminal equipment embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.
[0051] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.
[0052] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.
Claims
1. A detection system for ACFM detection of thick coatings, characterized in that: The system comprises: a U-shaped ferrite yoke with adjustable span, a detection probe with a built-in TMR sensor, a signal excitation and conditioning module and a visualization processing module; Among them, the signal excitation and conditioning module is used to control the excitation frequency of the U-shaped ferrite yoke during the detection process, the U-shaped ferrite yoke is used to provide a magnetic field that meets the preset magnetic field strength conditions for the workpiece to be tested, the detection probe with a built-in TMR sensor is used to detect the magnetic field change data of the workpiece to be tested under the action of the U-shaped ferrite yoke, and the visualization processing module is used to receive the magnetic field change data detected by the detection probe and visualize the magnetic field change data.
2. A detection system for thick coating ACFM detection as claimed in claim 1, characterized in that: The span of the U-shaped ferrite yoke is determined according to the coating thickness of the workpiece to be measured, so that the intensity of the magnetic field passing through the workpiece to be measured meets the preset magnetic field intensity condition.
3. A detection system for thick coating ACFM detection as claimed in claim 1, characterized in that: The detection probe with a built-in TMR sensor is arranged between two sides of the U-shaped ferrite yoke and contacts the test surface of the workpiece to be tested.
4. A detection system for thick coating ACFM detection as claimed in claim 1, characterized in that: The visualization processing module receives the magnetic field change data detected by the detection probe through the AD acquisition function of the STM32 chip.
5. A detection system for thick coating ACFM detection as claimed in claim 1, characterized in that: The visualization processing module visualizes the magnetic field change data through Visual Studio software.
6. The method for classifying motor imagery based on multi-view features as claimed in claim 1, characterized in that: When the coating thickness of the workpiece to be tested is 10 mm, the signal excitation and conditioning module is used to control the excitation frequency of the U-shaped ferrite yoke during the detection process to be a detection frequency of 5 KHz, and the yoke span of the U-shaped ferrite yoke is 30 mm.
7. A detection method for ACFM detection of thick coatings, characterized in that: The method comprises: Obtaining the coating thickness of the workpiece to be measured, and determining the yoke span and excitation frequency of the U-shaped ferrite yoke when a preset magnetic field strength condition is satisfied by using a finite element method according to the coating thickness; The U-shaped ferrite yoke is controlled to detect the workpiece to be tested according to the yoke span and the excitation frequency through the signal excitation and conditioning module, and the magnetic field change data of the workpiece to be tested under the action of the U-shaped ferrite yoke is detected through a detection probe with a built-in TMR sensor; The magnetic field change data is visualized through a visualization processing module.