Light supplementing system and light supplementing device for photometric stereo method

Abstract

The utility model discloses a photometric stereo method light supplementing system which is applied to subway train door lock visual detection and comprises a plurality of adjustable light source modules, a visual detection camera and an analysis unit. The subway train door lock is illuminated based on the adjustable light source module; the plurality of adjustable light source modules are uniformly distributed around the subway train door lock; image acquisition of the subway train door lock is realized based on the visual detection camera; the analysis unit is connected with the visual inspection camera to obtain an image, and the analysis unit adjusts the illumination angles and the illumination intensity of the plurality of adjustable light source modules based on the obtained image; through the plurality of adjustable light source modules, the angle and the intensity of light are accurately controlled by combining a photometric stereo method; the surface of the door lock is uniformly illuminated, and an over-bright or over-dark area is avoided.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of visual detection of subway train door locks, and in particular to a photometric stereo method light supplementing system and a light supplementing device. BACKGROUND

[0002] During the operation of a subway train, the state of the door lock is crucial to the safe operation of the train. Traditional door lock detection methods mainly rely on manual inspection or sensor detection, and these methods have the problems of low detection accuracy, low efficiency and being susceptible to environmental influences.

[0003] With the development of computer vision technology, methods based on visual detection have gradually been applied, but due to the complex light inside a subway train, traditional methods do not perform well under low light conditions. CONTENT OF THE UTILITY MODEL

[0004] To solve the above problems, the application provides a photometric stereo method light supplementing system applied to visual detection of a subway train door lock, comprising:

[0005] A plurality of adjustable light source modules for illuminating the subway train door lock; the plurality of adjustable light source modules are uniformly distributed around the subway train door lock;

[0006] A visual detection camera for image acquisition of the subway train door lock;

[0007] An analysis unit connected to the visual detection camera to obtain images, the analysis unit adjusting the illumination angle and intensity of the plurality of adjustable light source modules based on the obtained images.

[0008] The adjustable light source module comprises a light-emitting surface, and the maximum length of the light-emitting surface close to one side of the subway train door lock is greater than the maximum length of the subway train door lock in the direction parallel to the light-emitting surface.

[0009] The analysis unit analyzes the normal vector distribution of the surface of the subway train door lock based on the images of the subway train door lock, and determines the optimal illumination angle and intensity based on the normal vector distribution.

[0010] The adjustable light source module comprises an LED lamp, a mechanical arm structure and a light intensity controller; the LED lamp provides illumination, the mechanical arm structure adjusts the illumination angle, and the light intensity controller adjusts the illumination intensity.

[0011] The illumination direction of the adjustable light source module is determined based on Slants and Tilts angles, the Slants angle is 30° to 60°, and the Tilts angles are uniformly distributed around the object.

[0012] The photometric stereo light supplementing system has an adaptive adjustment function, and can automatically adjust the intensity and angle of the light source to adapt to different lighting conditions according to changes in ambient light.

[0013] The photometric stereo light supplementing system has a dynamic adjustment mechanism, which can update the image information of the door lock in real time during detection, and adjust the light angle and intensity of each light source module accordingly, to ensure that the door lock surface is always in the best lighting condition.

[0014] The analysis unit further includes an image preprocessing module, which removes noise and enhances image quality.

[0015] The alarm unit is connected to the analysis unit, which analyzes the subway train door lock and outputs the analysis result to the alarm unit, and the alarm unit outputs an alarm signal based on the analysis result.

[0016] The application also provides a light supplementing device, comprising:

[0017] The photometric stereo light supplementing system as claimed in any one of the above;

[0018] The fixing assembly is used to fix the adjustable light source module and the visual detection camera.

[0019] Compared with the prior art, the application has at least one of the following beneficial effects:

[0020] 1. By using multiple adjustable light source modules and combining photometric stereo method to accurately control the light angle and intensity, the door lock surface is evenly illuminated, avoiding the occurrence of overly bright or dark areas.

[0021] 2. The visual detection camera can accurately obtain the three-dimensional structural information of the door lock, effectively detecting defects with three-dimensional characteristics such as concave and convex.

[0022] 3. The system can automatically adjust the intensity and angle of the light source according to changes in ambient light, adapting to different lighting conditions.

[0023] 4. By monitoring the door lock state in real time, abnormal conditions can be found in time, ensuring the safe operation of the subway train. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments description. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative labor based on these drawings. Among them:

[0025] Figure 1 The framework schematic diagram of an embodiment of the photometric stereo light supplement system provided by the present application is shown in the figure.

[0026] Figure 2 The framework schematic diagram of an embodiment of the light supplement device provided by the present application is shown in the figure. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be described clearly and completely in the following with the drawings in the embodiments of the present application. It can be understood that the specific embodiments described here are only used to explain the present application, but not limit the present application. In addition, it should be noted that, for the convenience of description, only the parts related to the present application are shown in the drawings, but not all the structures. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0028] The terms "first", "second", etc. in the present application are used to distinguish different objects, but not to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, the process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but optionally includes the steps or units not listed, or optionally includes other steps or units inherent to the process, method, product or device.

[0029] In this paper, the phrase "embodiment" means that the specific features, structures or characteristics described in conjunction with the embodiment can be included in at least one embodiment of the present application. The phrase appears at various places in the specification does not necessarily refer to the same embodiment, nor is it independent or alternative to other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0030] In the prior art, the lighting mode of a single light source is difficult to provide sufficient and uniform illumination, making it difficult to clearly image some details (such as tiny scratches, wear or assembly gaps) of the door lock surface. In addition, the existing light supplementing mode lacks effective support for photometric stereo method, and cannot accurately adjust the illumination angle and intensity according to the three-dimensional shape and reflection characteristics of the door lock surface, thereby affecting the accuracy and reliability of visual detection; therefore, there is an urgent need for a light supplementing system capable of improving the accuracy of door lock visual detection under complex lighting conditions. In this regard, the present application provides a photometric stereo method light supplementing system applied to metro train door lock visual detection; as shown in Figure 1 Figure 1 The framework schematic diagram of an embodiment of the photometric stereo method light supplementing system provided by the present application includes a plurality of adjustable light source modules, a visual detection camera and an analysis unit.

[0031] The metro train door lock is illuminated based on the adjustable light source modules; the plurality of adjustable light source modules are uniformly distributed around the metro train door lock; for example, in an embodiment:

[0032] A light source module is installed above the door lock for providing top illumination.

[0033] A light source module is installed below the door lock for providing bottom illumination.

[0034] A light source module is installed on the left side and right side of the door lock for providing side illumination.

[0035] In this embodiment, the four light source modules are uniformly distributed around the metro train door lock, that is, the interval angle of any two adjacent light source modules is 90°; in other embodiments, three, five or six light source modules can be provided, and the interval angle of any two adjacent light source modules is adjusted accordingly, which is not limited herein.

[0036] By uniformly distributing a plurality of light source modules around the door lock, the problem of uneven illumination caused by a single light source can be avoided; light sources in different directions can cover all surface areas of the door lock, eliminate shadows and overly bright areas, and make the illumination of the entire door lock surface more uniform.

[0037] Image acquisition of the metro train door lock is realized based on the visual detection camera; the visual detection camera is installed close to the metro train door lock to ensure that it can fully cover all surface areas of the door lock; the number and installation position of the camera can be adjusted according to actual needs, for example, in an embodiment, four cameras are installed above, below, on the left side and on the right side of the metro door lock to obtain complete image data; in other embodiments, the number and installation position of the camera can be adjusted as needed, which is not limited herein.

[0038] ​The visual inspection camera can capture clear and high-quality images of the door lock with the cooperation of the multi-light source module; the high-resolution images provide a reliable data foundation for subsequent three-dimensional information extraction and defect detection; the installation position of the camera is optimized to cover all surface areas of the door lock, avoiding any details being missed; combined with multi-angle light source illumination, it can capture small scratches, wear or other defects on the surface of the door lock more clearly.

[0039] The analysis unit is connected to the visual inspection camera to obtain images, and the analysis unit adjusts the illumination angle and intensity of the multiple adjustable light source modules based on the obtained images; the working steps of the analysis unit for metro train door lock detection are described in detail below:

[0040] The visual inspection camera captures multiple images of the door lock under different lighting conditions.

[0041] After the analysis unit receives the images, it first performs denoising to remove interference factors in the images.

[0042] Using photometric stereo technology, the analysis unit calculates the normal vector distribution of the door lock surface to generate a three-dimensional model.

[0043] Based on the three-dimensional model, the analysis unit calculates the optimal illumination angle and intensity of each light source module.

[0044] The analysis unit sends control instructions to the adjustable light source modules to adjust the light angle and intensity.

[0045] During the detection process, the system updates image information in real time and dynamically adjusts light source parameters to adapt to changes in the door lock state.

[0046] The system can adjust light source parameters in real time according to changes in the door lock state to adapt to different detection needs; it has high automation and does not require human intervention, improving the flexibility and robustness of the system; by accurately calculating the optimal illumination angle and intensity, it avoids missed or false detections caused by uneven lighting in traditional methods; high-quality image acquisition and three-dimensional information extraction significantly improve the reliability of detection.

[0047] In summary, the photometric stereo light supplement system of the present application is applied to metro train door lock visual inspection, including multiple adjustable light source modules, a visual inspection camera and an analysis unit; the metro train door lock is illuminated based on the adjustable light source modules; the multiple adjustable light source modules are evenly distributed around the metro train door lock; image acquisition of the metro train door lock is realized based on the visual inspection camera; the analysis unit is connected to the visual inspection camera to obtain images, and the analysis unit adjusts the illumination angle and intensity of the multiple adjustable light source modules based on the obtained images through the multiple adjustable light source modules, and combines photometric stereo to accurately control the light angle and intensity, so that the door lock surface is uniformly illuminated, avoiding the appearance of overly bright or dark areas.

[0048] Optionally, the adjustable light source module includes a light-emitting surface, the maximum length of the light-emitting surface near one side of the subway train door lock is greater than the maximum length of the subway train door lock in the direction parallel to the light-emitting surface; the maximum length of the subway train door lock in the direction parallel to the light-emitting surface is measured (for example, the door lock width is 30 cm); the size of the light-emitting surface is designed so that the maximum length of the light-emitting surface near the door lock is greater than 30 cm (for example, set to 40 cm); when installing the light source module, the light-emitting surface is adjusted to a proper distance from the door lock to ensure that the light can uniformly cover the surface of the door lock.

[0049] The larger size of the light-emitting surface allows the light to cover all surface areas of the door lock, avoiding uneven lighting caused by a too small light-emitting surface; uniform lighting helps the visual inspection system to more clearly capture the detailed features of the door lock surface; the larger light-emitting surface can better illuminate the edges and corners of the door lock, reducing the impact of shadows and blind areas; improving the ability to identify minor scratches, wear and tear or other defects, significantly improving detection accuracy.

[0050] Optionally, the analysis unit analyzes the normal vector distribution of the subway train door lock surface based on the image of the subway train door lock, and determines the best lighting angle and lighting intensity based on the normal vector distribution; the normal vector represents the direction of each point on the door lock surface and further obtains the inclination and orientation; by analyzing the reflection characteristics under different lighting conditions, the geometric structure of the door lock surface is derived; the analysis unit obtains the best lighting angle and lighting intensity based on the obtained inclination and orientation, ensuring that the light can uniformly cover the entire surface and avoiding the occurrence of overly bright or dark areas.

[0051] The analysis unit accurately calculates the normal vector distribution of the door lock surface through photometric stereo method, which can more accurately identify minor defects; dynamically adjusting the light source parameters ensures that the door lock surface is always under the best lighting conditions, reducing the false detection problems caused by insufficient or uneven lighting.

[0052] The normal vector distribution provides three-dimensional information of the door lock surface, allowing the system to better reflect the geometric features of the door lock; for defects with depth characteristics such as depressions or protrusions, clearer imaging is achieved, improving the reliability of detection.

[0053] Optionally, the adjustable light source module includes LED lights, mechanical arm structures and light intensity controllers; the LED lights provide lighting, which can provide sufficient lighting intensity to ensure clear imaging under complex lighting conditions; compared with traditional light sources such as incandescent or halogen lamps, LED lights have lower energy consumption and longer service life, reducing the operating cost of the system.

[0054] The mechanical arm structure adjusts the illumination angle. The mechanical arm can flexibly adjust the angle of the light source, so that the light can uniformly cover different areas of the door lock surface, avoiding the appearance of shadow or over-bright areas. The high-precision motion control capability of the mechanical arm ensures that the light angle can accurately match the optimal value calculated by the analysis unit.

[0055] The light intensity controller adjusts the illumination intensity. The light intensity controller can accurately adjust the light source intensity as needed to prevent some parts of the door lock from affecting the detection effect due to over-brightness or over-darkness. By optimizing the illumination intensity, the system can obtain higher contrast and clearer images, improving the accuracy of visual detection.

[0056] The combination of the LED lamp, mechanical arm structure, and light intensity controller forms a highly integrated light source module, achieving dual regulation of light source angle and intensity. By accurately adjusting the light angle through the mechanical arm and dynamically optimizing the light source intensity through the light intensity controller, the system can obtain high-quality images of the door lock surface, significantly improving the detection accuracy and reliability.

[0057] Optionally, the illumination direction of the adjustable light source module is determined based on Slants and Tilts angles. The Slants angle refers to the angle between the camera optical axis and the illumination direction, which determines the direction from which the light shines on the door lock surface. The Tilts angle refers to the angle measured in the object plane or any plane parallel to it, which is uniformly distributed around the object. The Tilt angle describes the direction of the light relative to the center of the image, for example, 0° indicates that the light comes from the right, and 90° indicates that the light comes from the top.

[0058] The Slants angle is 30° to 60°, and the Tilts angle is uniformly distributed around the object. The Slants angle range is limited to 30° to 60°, which can effectively avoid the appearance of over-bright or over-dark areas, ensuring that the light shines on the door lock surface at an appropriate inclination angle. The Tilts angle is uniformly distributed around the object, allowing the light to cover all surface areas of the door lock from multiple directions, avoiding shadows and blind spots.

[0059] It should be noted that in this embodiment, the Slants angle is 30° to 60°, and in other embodiments, the Slants angle range can take additional values, which are not limited in this regard.

[0060] Optionally, the photometric stereo light supplementing system has an adaptive adjustment function, which can automatically adjust the intensity and angle of the light source to adapt to different lighting conditions according to the change of the ambient light; the adaptive adjustment function enables the system to automatically adjust the light source parameters according to the change of the ambient light to adapt to different detection conditions; whether it is a bright platform environment or a dim tunnel, the system can maintain stable detection performance; by dynamically adjusting the angle and intensity of the light source, it ensures that the door lock surface is always in the best lighting conditions, avoiding imaging problems caused by changes in ambient light; high-quality image acquisition provides a reliable data foundation for subsequent three-dimensional information extraction and defect detection.

[0061] Optionally, the photometric stereo light supplementing system has a dynamic adjustment mechanism, which can update the image information of the door lock in real time during the detection process and adjust the light angle and intensity of each light source module accordingly to ensure that the door lock surface is always in the best lighting conditions.

[0062] Optionally, the analysis unit further comprises an image preprocessing module for removing noise and enhancing image quality.

[0063] Optionally, the photometric stereo light supplementing system further comprises an alarm unit (not shown in the figure), which is connected to the analysis unit; the analysis unit analyzes the subway train door lock and outputs the analysis result to the alarm unit; the alarm unit outputs an alarm signal based on the analysis result.

[0064] The analysis unit analyzes the collected data according to the preset door lock state standard to determine whether there is an abnormal situation (such as scratches, wear, looseness or other defects); if the analysis unit detects an abnormal situation, it will send the analysis result (including defect type, location and severity information) to the alarm unit; after receiving the analysis result, the alarm unit generates a corresponding alarm signal based on the set threshold or rules; the alarm signal can be an audible and visual alarm (such as a buzzer, warning light), screen prompt or remote notification, etc., without any limitation.

[0065] The alarm unit can timely detect abnormal conditions of the door lock and remind the staff to take measures through the alarm signal to avoid safety accidents caused by door lock failure; real-time monitoring and early warning function significantly improves the safety of the subway train; the immediate generation and transmission of the alarm signal enable the maintenance personnel to quickly locate the problem and take action, shortening the fault handling time.

[0066] The application also provides a light supplementing device, as shown in Figure 2 The frame diagram of an embodiment of the light supplementing device provided by the application comprises: Figure 2 The frame diagram of an embodiment of the light supplementing device provided by the application comprises:

[0067] The photometric stereo light supplementing system of any of the above embodiments;

[0068] A securing assembly for securing an adjustable light source module and a vision detection camera.

[0069] In several embodiments provided in the present application, it should be understood that the disclosed methods and devices can be implemented in other manners. For example, the embodiments of the device described above are merely schematic, and the division of the modules or units is merely logical function division, and there can be another division manner in actual implementation. For example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In this way, the actual division of the modules or units can be different from the division in the embodiment.

[0070] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they can be located in one place, or they can be distributed on a plurality of network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0071] In addition, each functional unit in each embodiment of the present application can be integrated into a processing unit, or each unit can exist physically, or two or more units can be integrated into one unit. The integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0072] The above description is merely an embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation using the content of the specification and drawings, or direct or indirect application in other related technical fields, is also included in the patent protection scope of the present application.

Claims

1. A photometric stereoscopic light supplement system applied to visual detection of a subway train door lock, characterized in that, Comprising: a plurality of adjustable light source modules for illuminating the subway train door lock based on the adjustable light source modules; the plurality of adjustable light source modules are evenly distributed around the subway train door lock; a visual detection camera for image acquisition of the subway train door lock based on the visual detection camera; an analysis unit connected to the visual detection camera to obtain images, the analysis unit adjusts the illumination angle and intensity of the plurality of adjustable light source modules based on the obtained images.

2. The plenoptic stereoholography system of claim 1, wherein, The adjustable light source module includes a light-emitting surface, the maximum length of the light-emitting surface near one side of the subway train door lock is greater than the maximum length of the subway train door lock in the direction parallel to the light-emitting surface.

3. The photometric stereo light filling system of claim 1, wherein, The analysis unit analyzes the normal vector distribution of the surface of the subway train door lock based on the image of the subway train door lock, and determines the optimal illumination angle and intensity based on the normal vector distribution.

4. The plenoptic stereohlogy light supplementing system of claim 1, wherein, The adjustable light source module includes LED lights, a mechanical arm structure and a light intensity controller; the LED lights provide light, the mechanical arm structure adjusts the illumination angle, and the light intensity controller adjusts the illumination intensity.

5. The plenoptic stereohlogy light supplementing system according to claim 4, characterized in that, The illumination direction of the adjustable light source module is determined based on Slants and Tilts angles, the Slants angle is 30° to 60°, and the Tilts angles are evenly distributed around the object.

6. The plenoptic stereohlogy light supplementing system of claim 1, wherein, The photometric stereo light supplement system has an adaptive adjustment function, which can automatically adjust the intensity and angle of the light source to adapt to different lighting conditions according to the change of environmental light.

7. The plenoptic stereohlogy light supplementing system of claim 1, wherein, The photometric stereo light supplement system has a dynamic adjustment mechanism, which can update the image information of the door lock in real time during detection, and adjust the light angle and intensity of each light source module accordingly, so that the door lock surface is always in the best lighting condition.

8. The plenoptic stereohlogy light supplementing system according to claim 7, characterized in that, The analysis unit also includes an image preprocessing module for removing noise and enhancing image quality.

9. The plenoptic stereohlogy light supplementing system according to claim 8, characterized in that, It also includes an alarm unit connected to the analysis unit, the analysis unit analyzes the subway train door lock and outputs the analysis result to the alarm unit, and the alarm unit outputs an alarm signal based on the analysis result.

10. A light supplementing device, characterized in that Comprising: the photometric stereo light supplement system according to any one of claims 1-9; a fixing assembly for fixing the adjustable light source module and the visual detection camera.

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