Recognition system and method based on photometric stereo

Abstract

The system comprises an image acquisition module and a data processing device, the image acquisition module shoots an image according to a preset illumination mode and an object rotation angle to form a group of image data containing a plurality of different illumination and angle conditions, and the data processing device is used for processing the image data. The image acquisition device is used for acquiring image data and uploading the image data into the data processing device, and comprises a top shell, a controller, a bottom shell, a workpiece moving mechanism and an image acquisition mechanism. According to the photometric stereo-based recognition system and method, a more advanced fusion strategy is introduced, a photometric stereo physical illumination model and a physical perception self-attention mechanism are combined, the physical interpretability of features is enhanced, and the problem that a traditional fusion algorithm ignores an illumination physical rule is solved; and multi-angle image acquisition of different height layers of the workpiece is realized, image information of each side surface and front and back surfaces of the workpiece is acquired, and abundant data is provided for subsequent comprehensive analysis and three-dimensional reconstruction.

Description

Technical Field

[0001] The present invention relates to the field of computer vision technology, and in particular to a photometric stereo-based recognition system and method. Background Art

[0002] Photometric stereo technology is based on the principle that light has different effects on the surface of an object at different angles. By using multiple light sources to illuminate the object at different angles and capturing the corresponding images, the normal direction of each pixel (the direction perpendicular to the object's surface) can be calculated by observing the brightness changes of each pixel under different lighting conditions. Finally, the three-dimensional shape of the object's surface can be reconstructed using the normal information on the entire image. Compared with three-dimensional reconstruction technology based on structured light, photometric stereo technology does not require additional structured light projection equipment. It only needs to use light sources in different directions to obtain the three-dimensional information of the object. Therefore, it has advantages in some scenarios with simpler equipment requirements. In industrial production, photometric stereo technology can be used to detect defects and shape deviations on the surface of objects. For example, in automobile manufacturing, it is used to detect the flatness and paint quality of the car body surface. In electronic equipment manufacturing, it is used to detect defects on the chip packaging surface. In the prior art, in recognition systems based on photometric stereo, the accurate estimation of the surface normal vector of an object depends on the understanding of the physical laws of illumination. In actual scenes, different object surfaces have different reflective characteristics, such as specular reflection and diffuse reflection. Ignoring the physical laws of illumination will make it difficult for the algorithm to accurately distinguish these reflection types. Highlight areas may be misjudged as characteristic parts of the object, or certain reflective areas may be over-enhanced during fusion, thereby distorting the true information of the image, leading to problems such as image quality degradation, inaccurate feature extraction, and recognition and classification errors, reducing the reliability and practicality of the system. In addition, the existing photometric stereo recognition system can only collect image information of a single side of the workpiece, omitting the features of other sides of the workpiece, and unable to construct a complete three-dimensional model, affecting the understanding of the overall shape and spatial structure of the workpiece. In addition, in the current photometric stereo recognition system, the image collection device is a fixed camera that collects images from above the workpiece. The structure of the workpiece itself easily produces shadows that obscure its details, resulting in the loss of information in some areas of the image and the inability to clearly present its unique geometric shape and surface texture, limiting the capture of the comprehensive features of the workpiece. Summary of the Invention

[0003] The object of the present invention is to provide a recognition system and method based on photometric stereo to at least solve the problems mentioned in the prior art.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a recognition system and method based on photometric stereo, comprising: an image acquisition module and a data processing device, wherein the image acquisition module captures images according to a predetermined lighting mode and object rotation angle to form a set of image data under multiple different lighting and angle conditions, and uploads the image data to the data processing device.

[0005] Preferably, the data processing device includes: a preprocessing module, a feature extraction module, a recognition and classification module and a result output module; the preprocessing module preprocesses the collected image data; the feature extraction module estimates the normal vector based on the photometric stereo principle, combines the physical illumination model with the self-attention mechanism to construct physical perception, adds physical parameters as inductive bias, encodes spatiotemporal features for dynamic illumination sequences, and then converts the normal vector into a three-dimensional shape and extracts geometric features through a three-dimensional reconstruction algorithm; the recognition and classification module matches and compares the extracted features with a pre-established template library or feature database, and adopts a classification algorithm based on deep learning to learn and classify the features to determine the category or identity of the object; the result output module displays the recognition results to the user in an intuitive manner.

[0006] Preferably, the image acquisition device includes: a top shell, a controller, a bottom shell, a workpiece moving mechanism and an image acquisition mechanism; the controller is installed on the front side of the outer surface of the top shell; the bottom shell is arranged at the bottom of the top shell along the front-to-back direction; the workpiece moving mechanism is arranged on the front side of the upper surface of the bottom shell, and the workpiece moving mechanism can realize automatic transfer and flipping of the workpiece; the image acquisition mechanism is installed on the rear side of the inner top end of the controller, and the image acquisition mechanism can realize automatic multi-angle image data collection of the workpiece.

[0007] Preferably, the workpiece moving mechanism includes: a mounting frame, a mounting frame plate, a first limiting assembly, a moving frame, a first linear drive, a slot seat, a lifting frame, a first electric telescopic rod, a first mounting seat, a rotating seat, a connecting seat, an electric suction cup, and a second electric telescopic rod; the mounting frame is fixedly mounted on the front side of the upper surface of the bottom shell; the mounting frame plate is mounted on the top of the mounting frame along the front-to-back direction; the number of the first limiting assemblies is two, and the two first limiting assemblies are mounted on the left and right sides of the top of the mounting frame plate along the front-to-back direction; the number of the moving frames is two, and the two moving frames are respectively mounted on the top of the front and rear limiting ends of the left and right first limiting assemblies along the left and right directions; There are two first linear drives, and the two first linear drives are respectively installed at the top of the mounting frame along the front-to-back direction and located on the outside of the left and right first limit assemblies. The movable ends of the left and right first linear drives are respectively connected to the outside of the tops of the front and rear moving frames, and the first linear drive is electrically connected to the controller; there are two groups of slot seats, and each group of slot seats has two slot seats. The two groups of slot seats are respectively embedded in the left and right sides of the tops of the front and rear moving frames; there are two lifting frames, and the two lifting frames are respectively plugged into the bottom ends of the two groups of slot seats; there are two first electric telescopic rods, and the two first electric telescopic rods are respectively connected to the outside of the tops of the front and rear moving frames. The rods are respectively installed on the top of the two mobile frames in the up and down directions, the telescopic ends of the two first electric telescopic rods extend out of the lower surface of the mobile frame and are respectively connected to the top ends of the two lifting frames, and the first electric telescopic rod is electrically connected to the controller; the number of the first mounting seats is two, and the two first mounting seats are respectively installed at the bottom ends of the front and rear lifting frames in the up and down directions; the number of the rotating seats is two, and the two rotating seats are respectively rotatably connected to the inner ends of the two first mounting seats through rotating shafts, and the left and right sides of the axis of the rotating seat extend out of the outside of the first mounting seat; the number of the connecting seats is two groups, and the number of the connecting seats in each group is two, and one end of the two connecting seats They are fixedly connected to the left and right sides of the axis of the rotating seat respectively; the number of the electric suction cups is two, and the two electric suction cups are respectively installed on the inner sides of the front and rear rotating seats in the up and down directions, and the electric suction cups are electrically connected to the controller; the number of the second electric telescopic rods is two groups, and the number of the second electric telescopic rods in each group is two, and the two groups of second electric telescopic rods are respectively installed on the outer top ends of the front and rear first mounting seats through the rotating shaft seats in the up and down directions, and the telescopic ends of the two second electric telescopic rods are respectively connected to the other ends of the left and right connecting seats through the rotating shaft, and the second electric telescopic rods are electrically connected to the controller; wherein, a workpiece transfer component is provided under the mounting frame.

[0008] Preferably, the image acquisition mechanism includes: a linear motor, an annular frame, an annular inner rack and a multi-angle image collection component; the number of the linear motors is four, and the four linear motors are installed on the rear side of the top end of the inner cavity of the top shell at an interval of ninety degrees in the up and down directions, and the linear motor is electrically connected to the controller; the annular frame is circumferentially installed at the bottom of the four linear motors; the number of the annular inner racks is two, and the two annular inner racks are circumferentially installed on the upper and lower sides of the annular frame; the multi-angle image collection component is arranged on the inner side of the annular frame.

[0009] Preferably, the multi-angle image collection component includes: a moving part, a shell, a first slide frame, a second motor, a bevel gear set, a lead screw, a lead screw nut, a slider, a rotating frame, a limit frame, a second mounting seat, a third electric telescopic rod, a brake plate, a second slide frame, a second mounting frame, a third mounting seat, a first mounting plate, a fourth electric telescopic rod, a third motor, a second mounting plate, an image collector and a brightness adjuster; the moving part is arranged on the outside of the annular frame; the shell is installed in the middle of the front side of the moving part; the number of the first slide frames is two, and the two first slide frames are respectively installed at the upper and lower ends of the shell in the up and down directions; the number of the second motors is two, and the two The second motor is respectively installed on the upper and lower sides of the inner cavity of the second motor, and the second motor is electrically connected to the controller; the number of the bevel gear sets is two, and the bevel gears on one side of the two bevel gear sets are respectively installed on the rotating ends of the upper and lower second motors; the number of the lead screws is two, and the two lead screws are rotatably connected to the upper and lower sides of the outer surface of the shell through bearings and are located on the inner sides of the two first slide racks, and the inner ends of the shafts of the two lead screws extend into the inner cavity of the shell and are connected to the shafts of the bevel gears on the other side of the two bevel gear sets; the number of the lead screw nuts is two, and the two lead screw nuts are respectively screwed on the outside of the two lead screws; the number of the sliders is There are two groups, each group has two sliders, and the two groups of sliders are respectively arranged on the left and right sides of the upper and lower lead screw nuts and plugged into the inner cavities of the upper and lower first slide racks; there are two rotating racks, and the inner sides of one end of the two rotating racks are rotatably connected to the outer sides of the upper and lower groups of sliders through bearings; there are two limit racks, and the inner sides of one end of the two limit racks are rotatably connected to the outer ends of the upper and lower first slide racks through rotating shafts; there are two second mounting seats, and the two second mounting seats are rotatably connected to the inner sides of the other ends of the upper and lower rotating racks through rotating shafts; there are two third electric telescopic rods, and the two third electric telescopic rods are respectively The third electric telescopic rod is installed at the rear ends of the upper and lower second mounting bases, and the telescopic end of the third electric telescopic rod extends to the front side of the second mounting base, and the third electric telescopic rod is electrically connected to the controller; the number of the brake plates is two, and the two brake plates are respectively installed on the front sides of the telescopic ends of the upper and lower second mounting bases; the second slide frame is arranged in the front of the shell in the up-down direction, and the outer front sides of the upper and lower second mounting bases are respectively plugged into the upper and lower sides of the inner cavity of the second slide frame; the second mounting frame is arranged in the front side of the second mounting frame in the up-down direction; the third mounting frame is installed at the bottom end of the second mounting frame; the first mounting plate is rotatably connected to the outer front end of the third mounting frame by a rotating shaft in the up-down direction;There are two fourth electric telescopic rods, one end of each of which is rotatably mounted on the left and right top ends of the second mounting frame via a rotating shaft seat, and the other end of each of which is connected to the left and right ends of the rear side of the first mounting plate via a rotating shaft seat. The fourth electric telescopic rod is electrically connected to the controller; a third motor is mounted on the rear side of the first mounting plate, and the rotating end of the third motor extends from the central opening of the first mounting plate to the front end of the first mounting plate. The third motor is electrically connected to the controller; the second mounting plate is mounted in front of the rotating end of the third motor; an image collector is mounted on the front top of the second mounting plate, and the image collector is electrically connected to the controller; a brightness adjuster is mounted on the front side of the second mounting plate and is located below the image collector. The brightness adjuster is electrically connected to the controller.

[0010] Compared with the prior art, the present invention has the following beneficial effects: 1. The second motors on the upper and lower sides drive the lead screws on the upper and lower sides to rotate synchronously under the transmission of the bevel gear set, and the lead screw nuts on the upper and lower sides move synchronously outward or inward with the lead screws, so that the lead screw nuts on the upper and lower sides drive one end of the rotating frame at the corresponding position to move inward or outward, and the rotating frame drives the second mounting seat to move inward or outward along the inner cavity of the second slide frame under the limiting action of the limit frame, and after the second mounting seat moves to the designated position, the third electric telescopic rod outside the second mounting seats on the upper and lower sides extends to drive the brake plate to move forward, so that the brake plate fits against the inner wall of the second slide frame for fixation, and then, with the cooperation of the second slide frame, the second mounting frame is driven to drive the front image collector to move to a position directly above the workpiece. The brightness adjuster irradiates the workpiece on the surface of the workpiece bracket with a light source, and the image collector collects the image data of the workpiece and uploads it to the external data processing device through the controller. When it is necessary to collect the side direction data of the workpiece, the fourth electric telescopic rod extends to drive the first mounting plate to flip downward in front of the third mounting seat to a vertical state with the second mounting seat, and the third motor drives the second mounting plate to rotate, so that the image collector and the image collector rotate forward to a position aligned with the side direction of the workpiece. The moving part drives the image collector and the brightness adjuster to move circumferentially along the side of the workpiece, and adjusts the distance between the image collector and the brightness adjuster and the workpiece with the cooperation of the third electric telescopic rod and the second motor, thereby realizing the collection of image data on the side of the workpiece.

[0011] 2. Move the workpiece to the position below the mounting frame through the workpiece transfer component, and the first linear drive on the left drives the front moving frame to move above the workpiece under the limiting action of the first limit assembly. The first electric telescopic rod above the front moving frame extends to drive the lifting frame to move downward, and makes the electric suction cup under the lifting frame contact with the surface of the workpiece, and the electric suction cup adsorbs and grabs the workpiece. The second electric telescopic rod extends to drive one end of the connecting seat to move downward, so that the connecting seats on the left and right sides drive the rotating seat to drive the electric suction cup to rotate 90 degrees to the rear side. The first electric telescopic rod at the rear extends and shortens to drive the lifting frame downward or upward to the specified height position. The second electric telescopic rod at the rear extends and drives the connecting seat to drive the electric suction cup to flip the electric suction cup upward. The first linear drive on the right drives the rear moving frame to move to the corresponding position behind the workpiece under the limiting action of the first limit assembly, so that the rear electric suction cup contacts the rear surface of the workpiece and then adsorbs it. The front electric suction cup releases the adsorption of the workpiece, and the second electric telescopic rod at the rear shortens to drive the rear connecting seat to drive the rotating seat to flip downward, so that the rear electric suction cup cooperates to flip the workpiece.

[0012] In summary, the present invention introduces a more advanced fusion strategy, combining the physical illumination model of photometric stereo with the self-attention mechanism of physical perception, enhancing the physical interpretability of features, thereby solving the problem that traditional fusion algorithms ignore the physical laws of illumination, and realizing multi-angle image acquisition at different height levels of the workpiece, obtaining image information of all sides and front and back of the workpiece, providing rich data for subsequent comprehensive analysis and three-dimensional reconstruction. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic diagram of the present invention; Figure 2 for Figure 1 Schematic diagram of the image acquisition module structure; Figure 3 for Figure 2 Schematic diagram of the internal structure; Figure 4 for Figure 3 Exploded diagram of the workpiece moving mechanism; Figure 5 for Figure 4 A magnified view of point A; Figure 6 for Figure 4 Enlarged view of point B; Figure 7 for Figure 3 Exploded diagram of the image acquisition mechanism Figure 8 for Figure 7 Multi-angle image collection of component explosion diagrams; Figure 9 for Figure 8 Enlarged view of point C; Figure 10 for Figure 8 Enlarged view of point D.

[0014] In the figure: 1, top shell, 2, controller, 3, bottom shell, 4, workpiece moving mechanism, 41, mounting frame, 42, mounting frame plate, 43, first limiting assembly, 44, moving frame, 45, first linear drive, 46, slot seat, 47, lifting frame, 48, first electric telescopic rod, 49, first mounting seat, 410, rotating seat, 411, connecting seat, 412, electric suction cup, 413, second electric telescopic rod, 414, base, 415, second limiting assembly, 416, electric turntable, 417, second linear drive, 418, mounting base, 419, third limiting assembly, 420, workpiece bracket, 421, third linear drive, 5, image acquisition mechanism, 51, linear motor, 52, ring frame, 53, ring inner rack, 6 , multi-angle image collection component, 61, frame structure, 62, slot wheel, 63, slot gear, 64, connecting shaft, 65, first motor, 66, transmission gear set, 67, first mounting bracket, 68, shell, 69, first slide bracket, 610, second motor, 611, bevel gear set, 612, lead screw, 613, lead screw nut, 614, slider, 615, rotating bracket, 616, limit bracket, 617, second mounting seat, 618, third electric telescopic rod, 619, brake plate, 620, second slide bracket, 621, second mounting bracket, 622, third mounting seat, 623, first mounting plate, 624, fourth electric telescopic rod, 625, third motor, 626, second mounting plate, 627, image collector, 628, brightness adjuster. DETAILED DESCRIPTION

[0015] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0016] See also Figure 1-10 The present invention provides a technical solution: a recognition system and method based on photometric stereo, comprising: an image acquisition module and a data processing device, wherein the image acquisition module captures images according to a predetermined lighting mode and object rotation angle to form a set of image data containing multiple image data under different lighting and angle conditions, and uploads the image data to the data processing device; The data processing device includes: The preprocessing module preprocesses the collected image data by graying the image data, removing the salt and pepper noise in the image using the median filter algorithm, and enhancing the image contrast through histogram equalization to improve the image quality and the accuracy of subsequent processing; The feature extraction module uses an AI algorithm based on the principle of photometric stereo to calculate the brightness change of each pixel under different lighting conditions, and then estimates the normal vector of the object surface. It also combines the physical lighting model of photometric stereo with the self-attention mechanism of physical perception to construct physical perception. In the input layer of physical perception, physical parameters such as the incident angle of light, wavelength, and initial estimate of the surface normal vector are added to each pixel feature as an inductive bias, forcing the model to learn the physical association between reflectivity and geometric shape under different lighting conditions. For dynamic lighting sequences, the position encoding of physical perception is used to simultaneously encode spatial coordinates and timestamps to achieve global correlation modeling of spatiotemporal features. Then, through the 3D reconstruction algorithm, the normal vector information is converted into the 3D shape information of the object, and feature points, feature lines, and other geometric features are extracted from the 3D shape. The recognition and classification module matches and compares the extracted features with a pre-established template library or feature database, and uses a deep learning-based classification algorithm to learn and classify the features to determine the category or identity of the object; The result output module displays the recognition results to the user in an intuitive manner, showing the category, name or other relevant information of the object on the user's terminal screen, and saves the recognition results to the database for subsequent query and analysis.

[0017] As a preferred solution, further, Figure 2 and Figure 3 As shown, the image acquisition device includes: a top shell 1, a controller 2, a bottom shell 3, a workpiece moving mechanism 4 and an image acquisition mechanism 5; the controller 2 is installed on the front side of the outer surface of the top shell 1, and a preset program is set inside the controller 2 to automatically control the electrical components inside the device; the bottom shell 3 is arranged at the bottom of the top shell 1 along the front-to-back direction; the workpiece moving mechanism 4 is arranged on the front side of the upper surface of the bottom shell 3, and the workpiece moving mechanism 4 can realize automatic transfer and flipping of the workpiece; the image acquisition mechanism 5 is installed on the rear side of the internal top end of the controller 2, and the image acquisition mechanism 5 can realize automatic multi-angle image data collection of the workpiece.

[0018] As a preferred solution, further, Figure 4 、 Figure 5 and Figure 6As shown, the workpiece moving mechanism 4 includes: a mounting frame 41, a mounting frame plate 42, a first limiting assembly 43, a moving frame 44, a first linear drive 45, a slot seat 46, a lifting frame 47, a first electric telescopic rod 48, a first mounting seat 49, a rotating seat 410, a connecting seat 411, an electric suction cup 412 and a second electric telescopic rod 413; the mounting frame 41 is fixedly mounted on the front side of the upper surface of the bottom shell 3; the mounting frame plate 42 is mounted on the top of the mounting frame 41 along the front-to-back direction; there are two first limiting assemblies 43, and the two first limiting assemblies 43 are mounted on the left and right sides of the top of the mounting frame plate 42 along the front-to-back direction, and the limiting guide rails in the first limiting assembly 43 are mounted on the top of the mounting frame plate 42 along the front-to-back direction. The end and the outer sleeve of the limit guide rail are connected to the limit slider as the limit end; the number of movable frames 44 is two, and the two movable frames 44 are respectively installed on the top of the front and rear limit ends of the left and right first limit assemblies 43 along the left and right directions; the number of first linear drives 45 is two, and the two first linear drives 45 are respectively installed on the top of the mounting frame plate 42 along the front and back directions and are located on the outside of the left and right first limit assemblies 43, and the movable ends of the left and right first linear drives 45 are respectively connected to the outside of the top ends of the front and rear movable frames 44, the first linear drive 45 and the controller 2 are electrically connected, the first linear drive 45 is controlled by the controller 2, and the first linear drive 45 can drive the movable frame 44 in the front and back directions Movement; the number of slot seats 46 is two groups, and the number of each group of slot seats 46 is two. The two groups of slot seats 46 are respectively embedded in the left and right sides of the top of the front and rear mobile frames 44; the number of lifting frames 47 is two, and the two lifting frames 47 are respectively plugged into the bottom ends of the two groups of slot seats 46, and the lifting frames 47 can move up and down inside the slot seats 46; the number of first electric telescopic rods 48 is two, and the two first electric telescopic rods 48 are respectively installed on the top of the two mobile frames 44 in the up and down directions. The telescopic ends of the two first electric telescopic rods 48 extend out of the lower surface of the mobile frame 44 and are respectively connected to the top of the two lifting frames 47. The first electric telescopic rod 48 is electrically connected to the controller 2, and the first electric telescopic rod 48 is controlled by the controller 2 is controlled, the first electric telescopic rod 48 can drive the lifting frame 47 to move up and down by its own extension and contraction; there are two first mounting seats 49, and the two first mounting seats 49 are respectively mounted on the bottom ends of the front and rear lifting frames 47 in the vertical direction; there are two rotating seats 410, and the two rotating seats 410 are respectively rotatably connected to the inner ends of the two first mounting seats 49 via rotating shafts, and the left and right sides of the axis of the rotating seat 410 extend outside the first mounting seat 49, and the rotating seat 410 can rotate inside the first mounting seat 49; there are two groups of connecting seats 411, and each group of connecting seats 411 has two ends, and one end of the two connecting seats 411 is fixedly connected to the left and right sides of the axis of the rotating seat 410.There are two electric suction cups 412, which are respectively mounted on the inner sides of the front and rear rotating seats 410 in the up and down directions. The electric suction cups 412 are electrically connected to the controller 2, and the electric suction cups 412 are controlled by the controller 2. The electric suction cups 412 can absorb and grasp the workpiece; there are two groups of second electric telescopic rods 413, and the number of each group of second electric telescopic rods 413 is two. The number of second electric telescopic rods 413 is two groups, and the number of each group of second electric telescopic rods 413 is two. The two groups of second electric telescopic rods 413 are respectively mounted on the outer top ends of the front and rear first mounting seats 49 through the rotating shaft seats in the up and down directions, and the telescopic ends of the two second electric telescopic rods 413 are respectively connected to the other ends of the left and right connecting seats 411 One end is connected by a rotating shaft, and the second electric telescopic rod 413 is electrically connected to the controller 2. The second electric telescopic rod 413 is controlled by the controller 2. The second electric telescopic rod 413 can drive one end of the connecting seat 411 to move and rotate by its own extension and shortening. During the extension and shortening process of the second electric telescopic rod 413 itself, it can rotate synchronously with the cooperation of the pin seat at its own installation position; wherein, a workpiece transfer component is provided below the installation frame 41, and the workpiece transfer component includes: a base table 414, a second limiting component 415, an electric turntable 416, a second linear drive 417, an installation base plate 418, a third limiting component 419, a workpiece bracket 420 and a third linear drive 421; the base table 414 is installed on the bottom outer The top of the shell 3 and is located below the mounting frame 41; there are two second limit assemblies 415, and the two second limit assemblies 415 are respectively installed on the front and rear sides of the top of the base platform 414 along the left and right directions. The limit guide rails in the second limit assembly 415 are installed on the top of the base platform 414 along the left and right directions, and the outer sleeve of the limit guide rails is connected to the limit slider as the limit end; the electric turntable 416 is installed on the top of the limit ends of the two front and rear second limit assemblies 415, the electric turntable 416 is electrically connected to the controller 2, and the electric turntable 416 is controlled by the controller 2. The electric turntable 416 can drive the mounting base 418 to rotate clockwise or counterclockwise; the second linear drive 417 is installed on the top of the base platform 414 along the left and right directions and is located at the front On the inner side of the last two second limiting assemblies 415, the moving end of the second linear driver 417 is connected to the bottom of the electric turntable 416, the second linear driver 417 is electrically connected to the controller 2, the second linear driver 417 is controlled by the controller 2, and the second linear driver 417 can drive the electric turntable 416 to move in the left and right directions; the mounting base 418 is mounted on the top of the rotating end of the electric turntable 416 along the front-to-back direction; the number of the third limiting assemblies 419 is two, and the two third limiting assemblies 419 are respectively mounted on the left and right sides of the top of the mounting base 418 along the front-to-back direction, and the limiting guide rail in the third limiting assembly 419 is mounted on the top of the mounting base 418 along the front-to-back direction, and the outer portion of the limiting guide rail is sleeved with a limiting slider as a limiting end;The workpiece bracket 420 is mounted on top of the limiting ends of the left and right third limiting assemblies 419. A third linear actuator 421 is mounted on the top of the mounting base 418 in the front-to-back direction and is located inside the left and right third limiting assemblies 419. The movable end of the third linear actuator 421 is connected to the bottom of the workpiece bracket 420. The third linear actuator 421 is electrically connected to the controller 2 and is controlled by the controller 2 to drive the workpiece bracket 420 in the front-to-back direction.

[0019] As a preferred solution, further, Figure 7 As shown, the image acquisition mechanism 5 includes: a linear motor 51, an annular frame 52, an annular inner rack 53 and a multi-angle image collection component 6; the number of linear motors 51 is four, and the four linear motors 51 are installed on the rear side of the top end of the inner cavity of the top shell 1 at an interval of ninety degrees in the up and down directions. The linear motor 51 is electrically connected to the controller 2, and the linear motor 51 is controlled by the controller 2. The linear motor 51 can drive the annular frame 52 to rise and fall to a specified height position; the annular frame 52 is circumferentially installed at the bottom of the four linear motors 51; the number of annular inner racks 53 is two, and the two annular inner racks 53 are circumferentially installed on the upper and lower sides of the annular frame 52; the multi-angle image collection component 6 is arranged on the inner side of the annular frame 52.

[0020] As a preferred solution, further, Figure 8 、 Figure 9 and Figure 10As shown, the multi-angle image collection component 6 includes: a moving part, a shell 68, a first slide frame 69, a second motor 610, a bevel gear set 611, a lead screw 612, a lead screw nut 613, a slider 614, a rotating frame 615, a limit frame 616, a second mounting seat 617, a third electric telescopic rod 618, a brake plate 619, a second slide frame 620, a second mounting frame 621, a third mounting seat 622, a first mounting plate 623, a fourth electric telescopic rod 624, a third motor 625, a second mounting plate 626, an image collector 627 and a brightness adjuster 628; the moving part is arranged on the outside of the annular frame 52, and the moving part includes: a frame structure 61, a slot wheel 62, a slot gear 63, a connecting rod Connect the rotating shaft 64, the first motor 65, the transmission gear set 66 and the first mounting bracket 67; the frame structure 61 is sleeved on the outer side of the annular frame 52; the number of the slot body wheels 62 is two groups, and the number of each group of slot body wheels 62 is two. The two groups of slot body wheels 62 are respectively rotatably connected to the left and right sides and the upper and lower ends of the inner rear end of the frame structure 61 through the rotating shaft. The inner sides of the slot bodies of the two groups of slot body wheels 62 are respectively engaged with the outer ends of the upper and lower annular inner racks 53. The outer side of the slot body wheel 62 is provided with a slot along the circumferential direction and can move circumferentially along the outer side of the annular inner rack 53; the number of the slot body gears 63 is two groups, and the number of each group of slot body gears 63 is two. The two groups of slot body gears 63 are respectively rotatably connected to the left and right sides of the inner front end of the frame structure 61 through the rotating shaft. At the upper and lower ends, the inner sides of the groove bodies of the two groups of groove gears 63 are respectively engaged with the outer inner ends of the upper and lower annular inner racks 53, and the tooth groove parts in the groove body gears 63 are respectively meshed with the inner rack parts of the upper and lower annular inner racks 53, and the groove body gears 63 can move along the inner gear meshing of the annular inner rack 53; the number of connecting shafts 64 is two, and the two connecting shafts 64 are respectively installed at the inner ends of the axes of the upper and lower groove body gears 63 on the left and right sides along the up and down directions; the number of first motors 65 is two, and the two first motors 65 are installed at the left and right ends of the inner side of the frame structure 61, the first motors 65 and the controller 2 are electrically connected, the first motors 65 are controlled by the controller 2, and the first motors 65 can drive the transmission gear group 6 6 one side gear rotates clockwise or counterclockwise; there are two transmission gear sets 66, one side gears of the two transmission gear sets 66 are respectively keyed to the outside of the left and right connecting shafts 64, and the other side gears of the two transmission gear sets 66 are respectively installed on the rotating ends of the left and right first motors 65, and the transmission gear set 66 adopts the gear meshing setting on both sides to play a transmission role between the first motor 65 and the connecting shaft 64; the first mounting bracket 67 is installed at the outer front end of the frame structure 61, and the front end of the first mounting bracket 67 is connected to the shell 68; the shell 68 is installed in the middle of the front side of the moving part; there are two first slide slot racks 69, and the two first slide slot racks 69 are respectively installed at the upper and lower ends of the shell 68 along the up and down directions;There are two second motors 610, and the two second motors 610 are respectively installed on the upper and lower sides of the inner cavity of the second motor 610. The second motor 610 is electrically connected to the controller 2. The second motor 610 is controlled by the controller 2. The second motor 610 can drive the bevel gear on one side of the bevel gear set 611 to rotate clockwise or counterclockwise; there are two bevel gear sets 611, and the bevel gears on one side of the two bevel gear sets 611 are respectively installed on the rotating ends of the upper and lower second motors 610. The bevel gear set 61 adopts the bevel gear meshing setting on both sides to play a transmission role between the second motor 610 and the screw rod 612; there are two screw rods 612, and the two screw rods 612 are rotatably connected to the housing 68 through bearings. The outer surface of the upper and lower sides and are located on the inner sides of the two first slide racks 69, the inner ends of the axes of the two lead screws 612 extend into the inner cavity of the housing 68 and are connected to the axis of the bevel gears on the other side of the two bevel gear sets 611; the number of lead screw nuts 613 is two, and the two lead screw nuts 613 are respectively screwed on the outside of the two lead screws 612; the number of sliders 614 is two groups, and the number of each group of sliders 614 is two. The two groups of sliders 614 are respectively arranged on the left and right sides of the upper and lower lead screw nuts 613 and are plugged into the inner cavities of the upper and lower first slide racks 69, and the sliders 614 can move up and down in the inner cavity of the first slide rack 69; the number of rotating racks 615 is two, and the inner sides of one ends of the two rotating racks 615 are respectively rotatably connected to the upper The outer sides of the lower two groups of sliders 614; there are two limit frames 616, and the inner sides of one end of the two limit frames 616 are respectively connected to the outer ends of the upper and lower first slide frames 69 through a rotating shaft, and the limit frames 616 can rotate upward or downward on the outer sides of the first slide frames 69; there are two second mounting seats 617, and the two second mounting seats 617 are respectively connected to the inner sides of the other ends of the upper and lower rotating frames 615 through a rotating shaft; there are two third electric telescopic rods 618, and the two third electric telescopic rods 618 are respectively installed at the rear ends of the upper and lower second mounting seats 617, and the telescopic end of the third electric telescopic rod 618 extends to the front side of the second mounting seat 617, and the third electric telescopic rod 618 is electrically connected to the controller 2. The movable telescopic rod 618 is controlled by the controller 2. The third electric telescopic rod 618 can drive the brake plate 619 to contact the inner wall of the second slide frame 620 to achieve fixation by extending and shortening itself; there are two brake plates 619, and the two brake plates 619 are respectively mounted on the front side of the telescopic ends of the upper and lower second mounting seats 617; the second slide frame 620 is arranged in the front of the shell 68 along the up and down direction, and the outer front sides of the upper and lower second mounting seats 617 are respectively plugged into the upper and lower sides of the inner cavity of the second slide frame 620, and the second mounting seat 617 can move up and down in the inner cavity of the second slide frame 620; the second mounting frame 621 is arranged in the up and down direction at the front side of the second mounting frame 621; the third mounting seat 622 is mounted on the bottom end of the second mounting frame 621;The first mounting plate 623 is connected to the outer front end of the third mounting seat 622 by rotating the shaft in the up and down direction; there are two fourth electric telescopic rods 624, one end of the two fourth electric telescopic rods 624 is respectively rotatably mounted on the left and right top ends of the second mounting frame 621 through the rotating shaft seat, and the other end of the two fourth electric telescopic rods 624 is connected to the left and right ends of the rear side of the first mounting plate 623 through the rotating shaft seat, and the fourth electric telescopic rod 624 is electrically connected to the controller 2; the third motor 625 is mounted on the rear side of the first mounting plate 623, and the rotating end of the third motor 625 extends from the middle opening of the first mounting plate 623 to the front end of the first mounting plate 623, and the third motor 625 is electrically connected to the controller 2, and the third motor 625 is electrically connected to the controller 2. Controlled by controller 2, third motor 625 can drive second mounting plate 626 to rotate clockwise or counterclockwise. Second mounting plate 626 is mounted in front of the rotating end of third motor 625. Image collector 627 is mounted on the front top of second mounting plate 626. Image collector 627 is electrically connected to controller 2 and controlled by controller 2. Image collector 627 collects image data of the workpiece and transmits the collected data to controller 2. Brightness adjuster 628 is mounted on the front side of second mounting plate 626 and below image collector 627. Brightness adjuster 628 is electrically connected to controller 2 and controlled by controller 2 to adjust brightness.

[0021] The detailed connection means are well-known in the art. The following mainly introduces the working principle and process. The specific operation is as follows: Step 1: The worker places the workpiece on the surface of the workpiece transfer component, and the workpiece transfer component moves the workpiece into the inner cavity of the top shell 1 and moves it below the image acquisition mechanism 5; Step 2: The four-side linear motors 51 drive the annular frame 52 to move downward, so that the multi-angle image collection component 6 outside the annular frame 52 drops to a specified height position, and the second motors 610 on the upper and lower sides drive the bevel gears in the bevel gear set 611 at the corresponding position to rotate, so as to drive the upper and lower side lead screws 612 to rotate synchronously under the transmission of the bevel gear set 611, and the upper and lower side lead screw nuts 613 drive one end of the rotating frame 615 at the corresponding position to move inward or outward under the action of the rotational force of the lead screw 612, and the rotating frame 615 drives the second mounting seat 617 along the inner cavity of the second slide frame 620 under the limiting action of the limit frame 616. Move inward or outward, and after the second mounting seat 617 moves to the specified position, the third electric telescopic rod 618 outside the second mounting seats 617 on the upper and lower sides is extended to drive the brake plate 619 to move forward, so that the brake plate 619 is fitted with the inner wall of the second slide frame 620 for fixation, and then the second mounting frame 621 is driven to drive the front image collector 627 to move to the position just above the workpiece with the cooperation of the second slide frame 620, the brightness adjuster 628 illuminates the workpiece on the surface of the workpiece bracket 420 with a light source, and the image collector 627 collects the workpiece image data and uploads it to the external data processing device through the controller 2; Step 3: When it is necessary to collect data on the side direction of the workpiece, the third electric telescopic rod 618 and the second motor 610 drive the above structure to return to the starting position, the fourth electric telescopic rod 624 extends to drive the first mounting plate 623 to flip downward in front of the third mounting seat 622 to a perpendicular state to the second mounting bracket 621, and the third motor 625 drives the second mounting plate 626 to rotate, so that the image collector 627 and the image collector 627 rotate forward to a position aligned with the side direction of the workpiece, and the moving part drives the image collector 627 and the brightness adjuster 628 to move circumferentially along the side of the workpiece, and adjusts the distance between the image collector 627 and the brightness adjuster 628 and the workpiece with the cooperation of the third electric telescopic rod 618 and the second motor 610, thereby realizing image data collection on the side of the workpiece; Step 4: When it is necessary to collect image data of the other side of the workpiece, the third linear drive 421 and the second linear drive 417 drive the workpiece bracket 420 to move to the position below the mounting frame 41, and the first linear drive 45 on the left drives the front moving frame 44 to move above the workpiece under the limiting action of the first limiting component 43, and the first electric telescopic rod 48 above the front moving frame 44 extends to drive the lifting frame 47 to move downward, and makes the electric suction cup 412 under the lifting frame 47 contact with the surface of the workpiece, and the electric suction cup 412 absorbs and grabs the workpiece, and the second electric telescopic rod 413 extends to drive one end of the connecting seat 411 to move downward, so that the left and right connecting seats 411 drive the rotating seat 410 to drive the electric suction cup 412 to rotate ninety degrees to the rear side, and the rear first The electric telescopic rod 48 extends and shortens to drive the lifting frame 47 to move downward or upward to a specified height position, the rear second electric telescopic rod 413 extends to drive the connecting seat 411 to drive the electric suction cup 412 to flip the electric suction cup 412 upward, and the right first linear drive 45 drives the rear moving frame 44 to move to the corresponding position behind the workpiece under the limiting action of the first limiting component 43, so that the rear electric suction cup 412 contacts the rear surface of the workpiece and then adsorbs it, and the front electric suction cup 412 releases the adsorption of the workpiece, and the rear second electric telescopic rod 413 shortens to drive the rear connecting seat 411 to drive the rotating seat 410 to flip downward, so that the rear electric suction cup 412 cooperates to turn the workpiece over and place it on the surface of the workpiece bracket 420, and then collect image data of the other side of the workpiece: Step 5: The preprocessing module receives the image data uploaded by the image acquisition module, grayscales the received image data, converts the color image into a grayscale image, and then uses the median filter algorithm to process the grayscale image to remove the salt and pepper noise to make the image clearer. The denoised image is then subjected to a histogram equalization operation to enhance the image contrast and further improve the image quality to ensure the accuracy of subsequent processing. Step 6: The feature extraction module uses AI algorithms to process the pre-processed image data based on the principle of photometric stereo, calculates the brightness change of each pixel under different lighting conditions, and estimates the normal vector corresponding to each pixel on the object surface through the calculation of the above brightness change. The physical illumination model of photometric stereo is combined with the self-attention mechanism of physical perception to construct a physical perception model. In the input layer of the physical perception model, physical parameters such as the incident angle of illumination, wavelength, and initial estimated value of the surface normal vector are added to each pixel feature as an inductive bias, thereby forcing the model to learn the physical relationship between reflectivity and geometric shape under different lighting conditions, for dynamic lighting sequences. , using the position encoding function of the physical perception model, the spatial coordinates and timestamps are encoded at the same time to achieve global correlation modeling of spatiotemporal features, and the 3D reconstruction algorithm is used to convert the estimated normal vector information into the 3D shape information of the object. Feature points, feature lines and other geometric features are extracted from the obtained 3D shape information for subsequent recognition and classification. The recognition and classification module matches and compares the features extracted by the feature extraction module with the pre-established template library or feature database, and adopts a classification algorithm based on deep learning to learn and classify the extracted features. Through the above operations, the category or identity of the object is determined; Step 7: The result output module displays the recognition results obtained by the recognition and classification module to the user in an intuitive manner. For example, the category, name or other relevant information (such as the material of the object) of the object is clearly displayed on the terminal screen used by the user. At the same time, the recognition results are saved in the database to facilitate the user's subsequent query and analysis, and provide data support for further decision-making.

[0022] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A recognition system based on photometric stereo, characterized in that: include: An image acquisition module and a data processing device, wherein the image acquisition module captures images according to a predetermined lighting mode and object rotation angle to form a set of image data containing multiple image data under different lighting and angle conditions, and uploads the image data to the data processing device; The image acquisition device comprises: Top shell (1); A controller (2) is mounted on the front side of the outer surface of the top housing (1); A bottom shell (3) is arranged at the bottom of the top shell (1) along the front-back direction; A workpiece moving mechanism (4) is arranged on the front side of the upper surface of the bottom shell (3), and the workpiece moving mechanism (4) can realize automatic transfer and flipping of the workpiece; An image acquisition mechanism (5) is installed on the rear side of the top end of the controller (2). The image acquisition mechanism (5) can realize automatic multi-angle image data collection of the workpiece.

2. A photometric stereo recognition system according to claim 1, characterized in that: The data processing device includes: A preprocessing module preprocesses the collected image data; The feature extraction module estimates the normal vector based on the principle of photometric stereo, combines the physical illumination model with the self-attention mechanism to build physical perception, adds physical parameters as inductive bias, encodes spatiotemporal features for dynamic illumination sequences, and then uses a 3D reconstruction algorithm to convert the normal vector into a 3D shape and extract geometric features; The recognition and classification module matches and compares the extracted features with a pre-established template library or feature database, and uses a deep learning-based classification algorithm to learn and classify the features to determine the category or identity of the object; The result output module displays the recognition results to the user in an intuitive way.

3. The photometric stereo recognition system according to claim 2, characterized in that: The workpiece moving mechanism (4) comprises: A mounting frame (41) fixedly mounted on the front side of the upper surface of the bottom housing (3); A mounting frame plate (42) mounted on the top of the mounting frame (41) in a front-to-back direction; A first limiting assembly (43), wherein the number of the first limiting assemblies (43) is two, and the two first limiting assemblies (43) are installed on the left and right sides of the top end of the installation frame plate (42) along the front-back direction; A movable frame (44), wherein the number of the movable frames (44) is two, and the two movable frames (44) are respectively installed on the top of the front and rear limiting ends of the left and right first limiting assemblies (43); A first linear driver (45), the number of the first linear drivers (45) is two, the two first linear drivers (45) are respectively installed at the top of the mounting frame (42) along the front-back direction and are located on the outside of the left and right first limit assemblies (43), the movable ends of the left and right first linear drivers (45) are respectively connected to the outside of the top of the front and rear movable frames (44), and the first linear driver (45) is electrically connected to the controller (2); Slot seats (46), the number of the slot seats (46) is two groups, the number of the slot seats (46) in each group is two, and the two groups of slot seats (46) are respectively embedded in the left and right sides of the top of the front and rear movable frames (44); The lifting frames (47) are two in number, and the two lifting frames (47) are respectively plugged into the bottom ends of the two groups of slot seats (46).

4. The photometric stereo recognition system according to claim 3, characterized in that: The workpiece moving mechanism (4) further comprises: a first electric telescopic rod (48), wherein the number of the first electric telescopic rods (48) is two, and the two first electric telescopic rods (48) are respectively installed on the top of the two mobile frames (44) in the vertical direction, and the telescopic ends of the two first electric telescopic rods (48) extend out of the lower surface of the mobile frame (44) and are respectively connected to the top of the two lifting frames (47), and the first electric telescopic rods (48) are electrically connected to the controller (2); A first mounting seat (49), the number of the first mounting seats (49) being two, and the two first mounting seats (49) being respectively mounted at the bottom ends of the front and rear lifting frames (47) in the up-down direction; A rotating seat (410), wherein the number of the rotating seats (410) is two, and the two rotating seats (410) are rotatably connected to the inner ends of the inner sides of the two first mounting seats (49) via rotating shafts, and the left and right sides of the axis of the rotating seat (410) extend outside the first mounting seat (49); Connecting seats (411), the number of the connecting seats (411) is two groups, the number of the connecting seats (411) in each group is two, and one end of the two connecting seats (411) is fixedly connected to the left and right sides of the axis of the rotating seat (410) respectively; An electric suction cup (412), wherein the number of the electric suction cups (412) is two, and the two electric suction cups (412) are respectively installed on the inner sides of the front and rear rotating seats (410) in the up-down direction, and the electric suction cups (412) are electrically connected to the controller (2); The second electric telescopic rod (413) is provided in two groups, each group of the second electric telescopic rod (413) is provided with two second electric telescopic rods (413), the two groups of the second electric telescopic rod (413) are respectively installed on the outer top ends of the two first mounting seats (49) in the upper and lower directions through the rotating shaft seats, the telescopic ends of the two second electric telescopic rods (413) are respectively connected to the other ends of the two left and right connecting seats (411) through the rotating shaft, and the second electric telescopic rod (413) is electrically connected to the controller (2); Wherein, a workpiece transfer component is provided below the mounting frame (41).

5. The photometric stereo recognition system according to claim 4, characterized in that: The image acquisition mechanism (5) comprises: Linear motors (51), the number of the linear motors (51) is four, and the four linear motors (51) are installed at the rear side of the top end of the inner cavity of the top shell (1) at intervals of 90 degrees in the vertical direction, and the linear motors (51) are electrically connected to the controller (2); An annular frame (52) is circumferentially mounted on the bottom of the four linear motors (51); an annular inner rack (53), wherein the number of the annular inner racks (53) is two, and the two annular inner racks (53) are circumferentially mounted on the upper and lower sides of the annular frame (52); The multi-angle image collecting component (6) is arranged on the inner side of the annular frame (52).

6. The photometric stereo recognition system according to claim 5, characterized in that: The multi-angle image collecting component (6) includes: A moving part, the moving part being arranged outside the annular frame (52); A housing (68) mounted in the middle of the front side of the moving part; A first chute frame (69), wherein the number of the first chute frames (69) is two, and the two first chute frames (69) are respectively mounted at the upper and lower ends of the housing (68) in the upper and lower directions; A second motor (610), wherein the number of the second motors (610) is two, and the two second motors (610) are respectively installed on the upper and lower sides of the inner cavity of the second motor (610), and the second motor (610) is electrically connected to the controller (2); A bevel gear set (611), wherein the number of the bevel gear sets (611) is two, and the bevel gears on one side of the two bevel gear sets (611) are respectively mounted on the rotating ends of the upper and lower second motors (610); A lead screw (612), wherein the number of the lead screws (612) is two, and the two lead screws (612) are rotatably connected to the upper and lower sides of the outer surface of the housing (68) through bearings and are located on the inner sides of the two first slide racks (69), and the inner ends of the shafts of the two lead screws (612) extend into the inner cavity of the housing (68) and are connected to the shafts of the bevel gears on the other side of the two bevel gear sets (611); Screw nuts (613), the number of the screw nuts (613) is two, and the two screw nuts (613) are respectively screwed onto the outside of the two screw rods (612); Slide blocks (614), the number of the slide blocks (614) is two groups, the number of the slide blocks (614) in each group is two, the two groups of slide blocks (614) are respectively arranged on the left and right sides of the upper and lower lead screw nuts (613) and are plugged into the inner cavities of the upper and lower first slide slot frames (69); A rotating frame (615), wherein the number of the rotating frames (615) is two, and the inner sides of one end of the two rotating frames (615) are rotatably connected to the outer sides of the upper and lower sets of sliders (614) through bearings respectively; A limiting frame (616), wherein the number of the limiting frames (616) is two, and the inner sides of one end of the two limiting frames (616) are rotatably connected to the outer ends of the upper and lower first chute frames (69) respectively through a rotating shaft; A second mounting seat (617), the number of the second mounting seats (617) is two, and the two second mounting seats (617) are rotatably connected to the inner sides of the other ends of the upper and lower rotating frames (615) respectively through rotating shafts; a third electric telescopic rod (618), wherein the number of the third electric telescopic rods (618) is two, and the two third electric telescopic rods (618) are respectively mounted on the rear ends of the upper and lower second mounting seats (617), and the telescopic ends of the third electric telescopic rods (618) extend to the front side of the second mounting seat (617), and the third electric telescopic rods (618) are electrically connected to the controller (2); Braking plates (619), the number of the braking plates (619) is two, and the two braking plates (619) are respectively mounted on the front sides of the telescopic ends of the upper and lower second mounting seats (617); The second chute frame (620) is arranged in front of the shell (68) in the up-down direction, and the outer front sides of the upper and lower second mounting seats (617) are respectively plugged into the upper and lower sides of the inner cavity of the second chute frame (620); A second mounting frame (621) is arranged on the front side of the second mounting frame (621) in the up-down direction; A third mounting seat (622) is mounted on the bottom end of the second mounting frame (621); A first mounting plate (623) is rotatably connected to the outer front end of the third mounting seat (622) via a rotating shaft in the up-down direction; A fourth electric telescopic rod (624), the number of the fourth electric telescopic rod (624) is two, one end of the two fourth electric telescopic rods (624) is rotatably mounted on the top of the left and right sides of the second mounting frame (621) through a rotating shaft seat, and the other end of the two fourth electric telescopic rods (624) is connected to the left and right ends of the rear side of the first mounting plate (623) through the rotating shaft seat, and the fourth electric telescopic rod (624) is electrically connected to the controller (2).

7. The photometric stereo recognition system according to claim 6, characterized in that: The multi-angle image collecting component (6) further includes: a third motor (625) mounted on the rear side of the first mounting plate (623), wherein the rotating end of the third motor (625) extends from the central opening of the first mounting plate (623) to the front end of the first mounting plate (623), and the third motor (625) is electrically connected to the controller (2); A second mounting plate (626) mounted on the front side of the rotating end of the third motor (625); An image collector (627) is mounted on the front top of the second mounting plate (626), and the image collector (627) is electrically connected to the controller (2); A brightness adjuster (628) is mounted on the front side of the second mounting plate (626) and is located below the image collector (627). The brightness adjuster (628) is electrically connected to the controller (2).

8. A photometric stereo-based recognition method, applied to a photometric stereo-based recognition system as claimed in claim 7, characterized in that: The steps include: Step 1. Workpiece transfer and positioning: The worker places the workpiece on the workpiece transfer component, and the transfer component sends the workpiece to the bottom of the image acquisition mechanism (5) in the top shell (1) to prepare for image acquisition. Step 2. Multi-surface image acquisition: Frontal acquisition: the linear motor (51) drives the annular frame (52) to descend, driving the multi-angle image collection component (6) to reach a specified height, the second motor (610) drives the lead screw (612) through the bevel gear set (611), so that the lead screw nut (613) drives the rotating frame (615), prompting the second mounting seat (617) to move. After it is in place, the third electric telescopic rod (618) pushes the brake plate (619) to be fixed, so that the image collector (627) is located directly above the workpiece, the brightness adjuster (628) is illuminated, and the front image is collected and uploaded; Side acquisition: When acquiring side data, the relevant components reset the structure, the fourth electric telescopic rod (624) flips the first mounting plate (623), the third motor (625) rotates the second mounting plate (626), and the image collector (627) is aligned with the side. The moving part drives it and the brightness adjuster (628) to move along the side circumference and adjust the distance to complete the side image acquisition; Flipping acquisition: the second linear drive (421, 417) moves the workpiece bracket (420), the left first linear drive (45) drives the front moving frame (44), the first electric telescopic rod (48) causes the electric suction cup (412) to adsorb the workpiece, the second electric telescopic rod (413) drives the electric suction cup (412) to rotate and flip, the right first linear drive (45) drives the rear moving frame (44), the rear electric suction cup (412) adsorbs, the front side is released from adsorption, and the rear second electric telescopic rod (413) is shortened to flip the workpiece, and an image of the other side is acquired; Step 3. Image preprocessing: The preprocessing module receives the image, converts it to grayscale, then uses a median filter to remove salt and pepper noise, and finally performs histogram equalization to enhance contrast and improve image quality. Step 4. Feature extraction and classification: The feature extraction module uses photometric stereo principles and AI algorithms to calculate the estimated normal vector of pixel brightness changes. It then builds a model combining a physical illumination model with a self-attention mechanism, adds physical parameters to encode spatiotemporal features, and extracts geometric features through 3D reconstruction. The recognition and classification module compares these features with a database and uses a deep learning algorithm to determine the object's category or identity. Step 5. Result output and storage: The result output module displays the recognition results to the user.

Images