AOI image high-speed online acquisition device and method

Abstract

The invention relates to an AOI image high-speed on-line acquisition device and method. The AOI image high-speed on-line acquisition device comprises a vertical frame arranged on a base, a focusing assembly and a loading assembly, the X-axis moving module is transversely fixed on the vertical frame, the Z-axis moving module is vertically carried on a moving seat of the X-axis moving module, the linear array camera is fixed on the rotating module, the rotating module is fixed on a moving seat of the Z-axis moving module, and the positioning device is arranged on the vertical frame. The monitoring module is used for monitoring the position and the distance between the linear array camera and a detection target in the X-axis and Z-axis directions; the rotating platform is arranged on the base, a clamping groove used for placing a detection target is formed in the top of the rotating platform, and the driving assembly is arranged below the rotating platform and used for driving the rotating platform to drive the detection target to rotate by 180 degrees, so that the acquisition surface of the detection target always adapts to the one-way scanning direction of the linear array camera. According to the invention, while the imaging quality is ensured, the detection speed and the automation level are remarkably improved, and high-speed, continuous and constant-speed imaging is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of LCM module detection, and in particular to a high-speed online acquisition device and method for AOI images. Background Art

[0002] Liquid crystal display modules (LCMs) are highly integrated display units that combine LCD panels, driver circuits, backlights, and other key components. Their performance and reliability directly determine the display quality of end products. With the consumer electronics market's increasing demand for display quality and intensifying competition in the LCM industry, implementing comprehensive monitoring throughout the entire LCM production process has become a core means of ensuring product quality. In particular, the inspection of LCMs for optical performance and cosmetic defects is crucial for ensuring product reliability and user satisfaction.

[0003] For example, patent "CN119717322B" discloses an AOI-based LCM module detection system. Although it can improve detection efficiency and accuracy through automated conveying, positioning and scanning mechanisms, it still has significant bottlenecks. However, since the image acquisition surface of the LCM touch screen will inevitably have ups and downs within the allowable error range of industrial production, when the actual distance between the AOI camera and the target surface exceeds the camera's depth of field, it will cause image blur, seriously affecting the acquisition accuracy.

[0004] To solve the above-mentioned depth of field problem, line scan cameras are introduced in the existing technology for image acquisition. However, this also brings new difficulties. For example, after completing a single unidirectional scan, the line scan camera must be reset before starting the scanning and acquisition of the next target, which limits its efficiency. Alternatively, the line scan camera is moved alternately left and right to scan the next target. However, in this way, the linear images acquired by it need to frequently adjust the direction alignment logic when splicing them into a two-dimensional image. Otherwise, the edges of the target image will easily produce jagged distortion, uneven brightness, left-right inversion and other quality problems. In addition, the downstream processing module must also add an additional direction correction algorithm to identify and correct the left-right inverted mirror image, thereby greatly increasing the complexity of downstream model training and reducing the accuracy of defect classification. It increases system complexity and debugging difficulty, making it difficult to meet the real-time processing requirements of high-speed pipelines.

[0005] Based on this, it is necessary to propose a high-speed online acquisition device and method for AOI images. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a high-speed online AOI image acquisition device and method, which effectively solves the problems that the existing fixed-distance imaging mode is difficult to adapt to the surface undulations of the target to be detected; the image acquisition efficiency is low; the image splicing complexity during alternating scanning, and the edges of the acquired images are easily distorted, which interferes with the segmentation accuracy and increases the image processing burden.

[0007] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: an AOI image high-speed online acquisition device, comprising a stand, a focusing assembly and a loading assembly arranged on a base; the focusing assembly comprises a line array camera, an X-axis moving module, a Z-axis moving module, a rotating module and a positioning device, the X-axis moving module is fixed on the stand in the horizontal direction, the Z-axis moving module is mounted on the moving seat of the X-axis moving module in the vertical direction, the line array camera is fixed on the rotating module, the rotating module is fixed on the moving seat of the Z-axis moving module, the positioning device is arranged on the stand, and the positioning device is used to monitor the line array The position and distance between the camera and the detection target in the X-axis and Z-axis directions, and the positioning device is connected to the controller signal, and the controller drives the linear array camera to move back and forth along the X-axis and Z-axis on the mobile module; the object-carrying assembly includes a driving assembly and a rotating platform, the rotating platform is arranged on the base, and a slot for placing the detection target is opened on the top of the rotating platform, and a horizontal placement table is provided on the rotating platform; the driving assembly is arranged below the rotating platform, and is used to drive the rotating platform to drive the detection target to rotate 180 degrees, so that the collection surface of the detection target always adapts to the unidirectional scanning direction of the linear array camera.

[0008] Furthermore, the rotating platform includes a turntable, a telescopic extension plate, a base and a linkage assembly. The turntable is rotatably installed in the middle of the base through the linkage assembly. The telescopic extension plate is located below the turntable and is connected to the turntable through the linkage assembly. The driving assembly is connected to the telescopic extension plate. When the driving assembly controls the telescopic extension plate to expand or contract laterally, the turntable can be driven to rotate synchronously under the action of the linkage assembly.

[0009] Furthermore, the linkage assembly includes a connecting rod, a rotating pin and a column, a column is fixed in the middle of the base, and grooves are symmetrically opened on the column. The rotating pin is fixed to the bottom of the turntable, and the bottom of the rotating pin contacts the top surface of the column and can rotate along the circumference of the column; one end of the connecting rod is hinged to the telescopic expansion plate, and the other end is hinged to the rotating pin; when the telescopic expansion plate expands outward, the rotating pin can be driven by the connecting rod to move along the top surface of the column, thereby driving the turntable to rotate, until the rotating pin rotates into the groove, and the turntable rotates 180 degrees and is adapted to be clamped between the two telescopic expansion plates.

[0010] Furthermore, the driving assembly includes a cylinder, a connecting seat, a rocker arm, a slider and a guide rail. The guide rail is fixed to the bottom of the base, the slider is slidably installed on the guide rail, and a guide rod is provided on the slider. One end of the rocker arm is hinged to the output end of the cylinder, and the other end is hinged to the guide rod. The cylinder is driven to telescopically move by the controller, thereby driving the slider to move back and forth horizontally through the rocker arm to control the telescopic expansion plate to extend outward or retract inward and reset.

[0011] Furthermore, the positioning device includes a laser sensor and a grating sensor. The laser sensor is located on one side of the linear array camera and is fixed on the rotating module, and is used to detect the distance between the linear array camera and different acquisition positions on the detection target; the grating sensor includes a transmitting end and a receiving end, which are located on the left and right sides of the linear array camera and fixed oppositely on the stand, and are used to detect the movement distance of the linear array camera along the X-axis.

[0012] Furthermore, the laser sensor is located on one side of the linear array camera and is fixed on the connecting plate; the transmitting end and the receiving end of the grating sensor are symmetrically fixed on the left and right sides of the X-axis moving module; the laser sensor and the grating sensor transmit the distance signal along the Z-axis and the grating signal along the X-axis as braking signal inputs to the controller, and the controller is loaded with a fuzzy PID algorithm. After receiving the input signal, the controller drives the X-axis moving module and the Z-axis moving module to move the linear array camera to the optimal imaging distance, so that it maintains the correct focus, thereby scanning and collecting the touch screen.

[0013] Furthermore, when the fuzzy PID algorithm is applied, the Z-axis deviation is obtained by real-time distance measurement by the laser sensor, and the grating ruler synchronously provides the X-axis position of the linear array camera. The fuzzification module converts the above deviation value into a language variable, and then calls the preset fuzzy rule table to infer the fuzzy value of the output control quantity. Finally, the fuzzification is performed to obtain accurate motor control instructions to control the X-axis moving module, Z-axis moving module and rotation module to drive the linear array camera to move.

[0014] Furthermore, it also includes a robot arm, which is located at the front side of the rotating platform and is connected to the controller signal. The robot arm can pick up the detection target on the assembly line conveyor belt and place it in the card slot of the rotating platform.

[0015] Furthermore, a guide rail is provided on the base, and the stand is slidably mounted on the base, so that the stand can move toward the detection member under the action of a thrust.

[0016] The present invention also provides a high-speed online acquisition method for AOI images, comprising the following steps: Step 1: The robot grabs the LCM display from the assembly line and places it in the slot on the rotating platform. The controller activates the laser sensor and grating sensor to adjust the line scan camera to its initial position on the left. Step 2: Based on the positive and negative values ​​of the line scan camera's X-axis coordinate position output by the grating sensor, the controller triggers control of the drive cylinder. When the line scan camera is scanning in the forward direction, there is no need to rotate the display screen. When the line scan camera is scanning in the reverse direction, the controller controls the drive cylinder to extend, pushing the swing arm to swing and driving the slider on the guide rail to move horizontally. The slider drives the telescopic expansion plate outward through the guide rod, and at the same time drives the turntable to rotate, so that the display screen acquisition surface is facing the appropriate scanning direction. Step 3: Start the mobile module to control the linear scan camera to move along the X-axis. The laser sensor collects the Z-axis distance deviation between the camera and the display surface in real time, and the grating sensor synchronously feeds back the X-axis displacement signal. The controller dynamically adjusts the position of the linear scan camera using a fuzzy PID algorithm, drives the rotation module to rotate the linear scan camera 180 degrees, and drives the lifting module to adjust the Z-axis height of the linear scan camera to maintain optimal focus throughout the entire process. Step 4: The line scan camera maintains a constant speed and continuously scans in a unidirectional motion until the display screen is completely scanned. The captured line images are stitched into a complete two-dimensional image in real time and transmitted to the downstream image processing module. Step 5: After the scan is completed, the cylinder drives the telescopic expansion plate to retract and reset, and the turntable returns to its initial angle; the robot removes the inspected display screen and places a new target, and the device enters the next inspection cycle, realizing fully automatic and continuous operation of the assembly line.

[0017] The beneficial effects of the above technical solution are as follows: The high-speed online AOI image acquisition device and method provided by the present invention integrates laser displacement sensing with a linear array camera, dynamically driving the motors of each module based on fuzzy PID control, achieving real-time automatic and precise focusing of the linear array camera during the scanning process, ensuring that the target is always at the optimal depth of field. Furthermore, a 180-degree rotating platform is introduced to dynamically adjust the initial orientation of the display screen. By driving the touch screen and its placement platform in odd or even positions to rotate, it can adapt to linear array cameras with different initial positions, allowing the linear array camera to capture the touch screen during both reciprocating motion and complete high-quality image acquisition. This completely avoids the image stitching problems and distortion risks caused by bidirectional scanning, thereby achieving large-scale, high-resolution, and highly reliable online high-speed imaging. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a structural diagram of the pipeline working state of the present invention; Figure 2 It is a schematic diagram of the overall implementation structure of the present invention; Figure 3 Schematic diagram of the implementation structure of the focusing component; Figure 4 Schematic diagram of the top view of the rotating platform in different states; Figure 5This is a schematic diagram of the internal implementation structure of the rotating platform; Figure 6 It is a structural diagram of the telescopic expansion plate in the retracted state; Figure 7 This is a structural diagram of the telescopic expansion board in the expanded state.

[0019] Figure numbers: 1-feeding platform, 2-transfer platform, 3-manipulator, 4-base, 41-stand, 42-X-axis moving module, 421-transverse motor, 422-transverse seat, 423-control block, 43-Z-axis moving module, 431-connecting seat, 432-lifting motor, 433-lifting seat, 44-rotating module, 441-rotating table, 442-rotating motor, 443-rotating seat, 45-positioning device, 451-grating sensor, 452-laser sensor Device, 46-rotating platform, 461-turntable, 462-telescopic extension plate, 463-linking assembly, 4631-column, 4632-docking sleeve, 4633-connecting rod, 4634-groove, 4635-rotating arm, 4636-rotating pin, 4637-docking joint, 464-base, 465-slider, 466-cross rail, 47-driving assembly, 471-cylinder, 472-slide, 473-rocker, 48-line array camera, 5-feeding platform, 6-display screen. DETAILED DESCRIPTION

[0020] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments: Example 1. This embodiment aims to provide a high-speed online AOI image acquisition device, which is mainly used for defect detection of LCM modules. It addresses the problem that in the existing technology, the linear array camera must be reset before starting target acquisition after a single unidirectional scan; and the bidirectional alternating acquisition causes the captured linear images to be mapped and spliced ​​into a two-dimensional image, which easily causes quality problems such as image distortion, edge jaggedness, and mirror flipping (left-right reversal), which significantly increases computing resource consumption, makes it difficult to meet the real-time processing requirements of high-speed pipelines, and further increases the complexity of the system and the difficulty of debugging.

[0021] The present invention proposes a high-speed online AOI image acquisition device. This device uses a laser sensor to monitor the distance changes between a linear array camera and the target surface in real time, combines a grating sensor to accurately locate the X-axis coordinate, and employs a fuzzy PID algorithm to dynamically control multiple mobile modules. This allows the linear array camera to automatically maintain the optimal imaging distance during the scanning process, completely resolving the defocusing problem caused by the undulations of the screen surface. Furthermore, by providing a horizontally rotating platform, the present invention can automatically adjust the acquisition surface of the LCM screen to the same orientation as the linear array camera's scanning direction before inspection, thereby ensuring that all images are acquired in a uniform direction and meeting the defect detection needs of the LCM production line.

[0022] like Figure 1-7 As shown, a high-speed online acquisition device for AOI images includes a base 4, and a stand 41, a focusing assembly and a loading assembly arranged on the base 4, wherein the focusing assembly includes a linear array camera 48, an X-axis moving module 42, a Z-axis moving module 43, a rotating module 44 and a positioning device 45. Slide rails are symmetrically fixed on the base, and the stand 41 is slidably mounted on the slide rails. Under the action of thrust, the stand 41 can move linearly toward the detection target direction. The X-axis moving module is fixedly installed on the stand 41, the Z-axis moving module is fixed on the moving seat of the X-axis moving module, and the rotating module 44 is fixed on the moving seat of the Z-axis moving module. In actual application, the X-axis and Z-axis moving modules can be linear slide modules or screw modules.

[0023] In the specific implementation structure, such as Figure 1-3 As shown, in this embodiment, the X-axis moving module is a screw module, wherein the transverse motor 421 is connected to the end of the screw rod, and the transverse seat 422 is arranged on the module. Under the action of the transverse motor 421, the transverse seat 422 is moved back and forth horizontally along the X-axis. A U-shaped connecting seat 431 is fixed on the front side of the transverse seat 422, and a Z-axis moving module is provided on the connecting seat 431. Specifically, the top of the connecting seat 431 is rotatably connected to the lifting motor 432, and the output end of the lifting motor 432 is connected to the vertical screw rod for transmission. The lifting seat 433 is arranged on the module, and the lifting seat 433 is driven by the lifting motor 432 to move up and down (the X and Z axis moving modules are existing technologies and are not described here).

[0024] The rotating module is arranged on the lifting seat 433. Specifically, in this embodiment, the rotating module 44 includes a rotating table 441, a rotating motor 442 and a rotating seat 443, wherein the rotating motor 442 is fixed on the top of the connecting seat 431, and its output shaft is fixedly connected to the rotating seat 443. The rotating table 441 is fixed on the front side of the lifting seat 433. A through hole is opened on the rotating table 441. After the linear array camera 48 is fixedly mounted on the rotating seat 443, its output end passes through the through hole and extends vertically downward to the bottom of the rotating table 441, so that when the rotating motor 442 is driven to rotate, it can drive the rotating table 441 and the linear array camera 48 to rotate.

[0025] like Figure 3As shown, the positioning device 45 is mounted on the stand 41. In this embodiment, the positioning device 45 includes a laser sensor 452 and a grating sensor 451. The laser sensor 452 is located on one side of the line scan camera 48 and is fixed to the rotating base 443. It is used to detect the vertical distance between the line scan camera 48 and different acquisition positions on the detection target. The grating sensor 451 includes a transmitting end and a receiving end. Both are located on the left and right sides of the line scan camera 48 and symmetrically fixed to the stand 41. They are used to detect the movement distance of the line scan camera 48 along the X-axis. To ensure detection accuracy, in this embodiment, a reference block 423 is also fixed on the top of the traversing base 422 to serve as a signal reference between the input and output of the grating sensor 451.

[0026] Furthermore, the laser sensor 452 and the grating sensor 451 can transmit the distance signal along the Z axis and the grating signal along the X axis as braking signal input to the controller. The controller is equipped with a fuzzy PID algorithm. After receiving the input signal, it drives the X-axis moving module, the Z-axis moving module and the rotation module 44 to move the linear array camera 48 to the optimal imaging distance, and then maintains the correct focus, so that the detection target is located within the depth of field of the linear array camera 48. By scanning and collecting the touch screen, large-area high-resolution and accurate imaging is achieved, which is convenient for analyzing the quality level of the detection target.

[0027] In this embodiment, the detection target is the display screen 6. Based on the fuzzy PID algorithm in the controller, the distance between the line array camera 48 and the anisotropic conductive film area of ​​the display screen 6 is collected in real time by the laser sensor 452 and the grating sensor 451. The horizontal X-axis grating signal is also collected and stored in the (X, Z) data queue and placed in the buffer. When the line array camera moves horizontally to the X position, the lifting motor 432 is controlled by the innovative fuzzy PID to drive the line array camera 48 to the optimal imaging distance, maintaining correct focus. By determining the position of the line array camera 48 at the left or right end of the X axis, the rotation of the camera is adaptively adjusted to ensure that the unidirectional scanning direction of the line array camera 48 always matches the acquisition surface of the display screen 6, avoiding quality problems such as left-right reversal during imaging.

[0028] like Figure 2 As shown, a loading assembly is provided below the line array camera 48. In this embodiment, the loading assembly includes a driving assembly 47 and a rotating platform 46. The rotating platform 46 is mounted on the base 4 via a base 464 at its bottom. In actual application, a slide rail can be provided on the base 4. The base 464 is slidably mounted on the slide rail to facilitate adjustment of the position of the rotating platform 46 so that it is compatible with the manipulator 3 or the stand 41. After the position is determined, it can be limited by fasteners such as a screw. Figure 4-7As shown, the rotating platform 46 includes a turntable 461, a telescopic extension plate 462, a base 464 and a linkage assembly 463. The turntable 461 is rotatably mounted in the middle of the base 464 through the linkage assembly 463. The telescopic extension plate 462 is located below the turntable 461 and is connected to the turntable 461 through the linkage assembly 463; the driving assembly 47 is connected to the telescopic extension plate 462. When the driving assembly 47 controls the telescopic extension plate 462 to expand or contract laterally, the turntable 461 can be synchronously driven to rotate under the action of the linkage assembly 463. When the turntable 461 is rotated and moved upward to the top of the telescopic extension plate 462, the telescopic extension plate 462 is retracted and hidden to the bottom of the turntable 461. When the telescopic extension plate 462 is pulled outward, the turntable 461 rotates and is clamped downward at the inner center of the telescopic extension plate 462, thereby realizing a 180-degree reversing operation of the turntable 461.

[0029] In the specific implementation structure, such as Figure 5-7 As shown, in this embodiment, the linkage assembly 463 includes a connecting rod 4633, a rotating pin 4636 and a column 4631. The column 4631 is fixed in the middle of the base 464. The column 4631 is a double-layer structure. The inner and outer columns are both provided with conical grooves 4634, and the two grooves 4634 are symmetrically arranged. A rotating arm 4635 is rotatably installed between the column 4631 and the base 464. The two distal ends of the rotating arm 4635 are respectively hinged with a connecting rod 4633. The two connecting rods 4633 are connected to each other. The outer ends of 33 are respectively hinged at the bottom of the telescopic expansion plate 462; a docking sleeve 4632 is provided in the middle of the rotating arm 4635, and a rotating pin 4636 and a docking joint 4637 are symmetrically fixed to the bottom of the turntable 461. The docking joint 4637 is adapted to be assembled in the docking sleeve 4632 and can move up and down in the docking sleeve 4632 without moving out of the docking sleeve. The bottom of the rotating pin 4636 contacts the top surface of the column 4631 and can move in a circle along the top surface of the column 4631 on both sides.

[0030] When the telescopic expansion plate 462 is pulled outward to expand by the driving assembly 47, the connecting rod 4633 drives the rotating arm 4635 to swing, and then drives the turntable 461 to rotate under the action of the docking joint 4637 and the docking sleeve 4632, so that the rotating pin 4636 moves along the top surface of the column 4631 until the rotating pin 4636 rotates into the corresponding groove 4634, and the turntable 461 rotates 180 degrees and is adapted to be clamped between the telescopic expansion plates 462; and when the telescopic expansion plate 462 is driven to retract inward, the rotating pin 4636 can be moved out of the groove 4634 to the top surface of the column 4631 under the action of the connecting rod 4633, thereby driving the turntable to reset 180 degrees. At this time, the telescopic expansion plate 462 is adapted to be hidden at the bottom of the turntable 461.

[0031] like Figure 6 and 7As shown, in this embodiment, the driving assembly 47 includes a cylinder 471, a slide 472 and a rocker arm 473. Cross rails 466 are symmetrically fixed on the left and right sides of the base 464. Sliders 465 are slidably installed on the cross rails 466, and a guide rod is provided on the slider 465. One end of the connecting rod 4633 is hinged to the rotating arm 4635, and the other end is hinged to the guide rod. A track and a cylinder 471 are fixed vertically on the bottom surface of the base 464, and a slide 472 is slidably connected to the track. The output end of the cylinder 471 is perpendicular to the direction of the cross rail 466 and is fixedly extended to the slide 472. One end of the rocker arm 473 is hinged to the output end of the cylinder 471, and the other end is hinged to the guide rod of the slider 465. The cylinder 471 is driven to telescopically move by the controller, thereby driving the slider 465 to move back and forth in a straight line along the cross rail 466 through the rocker arm 473 to control the telescopic expansion plate 462 to extend outward or retract and reset inward.

[0032] The arrangement of the linkage assembly of the present invention couples the rotational motion of the turntable with the horizontal expansion and contraction motion of the telescopic extension plate through the connecting rod and the rotating pin. Only one driving source is required to pull the telescopic extension plate horizontally, and its linear motion can be directly converted into the circular motion of the rotating pin on the top surface of the column through the connecting rod, thereby accurately driving the turntable to complete a 180-degree rotation; effectively ensuring that the turntable can accurately stop at the target angle of 180 degrees every time, so that the collection surface of the part to be inspected is strictly aligned with the scanning direction of the linear array camera, providing a solid foundation for high-quality image acquisition.

[0033] The high-speed online AOI image acquisition device provided in this embodiment uses a laser sensor to monitor the distance changes between the linear array camera and the surface of the workpiece to be inspected in real time, combines a grating sensor to accurately locate the X-axis coordinate, and adopts a fuzzy PID algorithm to intelligently control the Z-axis lifting and rotation angles to ensure that the camera is always at the optimal imaging distance, effectively solving the defocus problem caused by surface undulations and ensuring image clarity. The object-carrying assembly can automatically flip the workpiece to be inspected 180 degrees so that its acquisition surface always adapts to the unidirectional scanning direction of the linear array camera, avoiding the switching pauses of traditional bidirectional scanning, achieving high-speed, continuous, and uniform imaging, and greatly improving inspection efficiency. In addition, the robot automatically loads and unloads materials, the turntable intelligently flips in a directional manner, the camera dynamically adjusts the focus and scans, and images are spliced ​​and transmitted in real time. The entire process is tightly connected and operates in a cycle, significantly reducing labor costs. While ensuring imaging quality, it significantly improves inspection speed and automation level. It is suitable for the high-speed online defect detection needs of precision manufacturing fields such as LCM.

[0034] Example 2, based on Example 1, this example provides a high-speed online acquisition method for AOI images, which specifically includes the following steps: Step 1: The robot arm located on transfer platform 2 automatically grabs the LCM display to be inspected from the loading platform (conveyor belt) of the assembly line and accurately places it in the preset slot on the top of the rotating platform. At the same time, the controller activates the laser sensor and grating sensor in the positioning device. According to the preset program or initial signal, it drives the X-axis moving module, Z-axis moving module and rotating module to move the assembly equipped with the linear array camera to a predefined starting position, that is, at the left or right end position of the scanning path.

[0035] Step 2: The controller reads the precise coordinate position information of the line scan camera on the X-axis provided by the grating sensor in real time. Based on the positive and negative characteristics of this position value (for example, setting the left side as a negative starting point and the right side as a positive value), it determines whether the line scan camera is about to scan in the forward direction (such as from left to right) or the reverse direction (such as from right to left). If it is determined to be scanning in the forward direction, the direction of the current acquisition surface of the object to be inspected exactly matches the scanning direction, and the scanning phase can be directly entered without touching the drive component of the carrier platform. If reverse scanning is detected, the controller immediately issues a command to the pneumatic cylinder and rotary motor. The rotary motor drives the line scan camera 180 degrees, and the pneumatic cylinder begins to extend, pushing the swing arm hinged to its output end to swing, which in turn drives the slider connected to it to move laterally on the fixed guide rail. The slider's movement transmits power through the guide rod, driving the left and right telescopic expansion plates to expand outward simultaneously. The linkage assembly precisely converts the expansion motion of the telescopic expansion plates into circular motion of the rotating pin at the bottom of the turntable on the top surface of the column, forcing the entire turntable to rotate 180 degrees. Once the turntable is rotated into position, the rotating pin engages the groove in the column, securing it firmly. The display's acquisition surface is now precisely flipped to align with the line scan camera's upcoming forward scanning direction. This ensures that scanning is always unidirectional, regardless of the incoming material direction. The line scan camera can capture high-quality images of the touch screen during both its reciprocating motion.

[0036] Step 3: The controller activates the X-axis motion module, driving the line scan camera to begin moving at a constant speed along the X-axis, scanning the display surface. During this movement, the positioning mechanism operates continuously: a laser sensor continuously measures the actual distance between the line scan camera lens and the current position on the display surface, calculating the real-time Z-axis height deviation. Simultaneously, a grating sensor accurately and synchronously provides feedback on the coordinates of each displacement point of the line scan camera on the X-axis. A fuzzy PID algorithm running within the controller receives these two key signals (Z-axis distance deviation and X-axis position) in real time.

[0037] The fuzzy PID algorithm first fuzzifies the actual digital deviation value, converting it into a fuzzy variable described in natural language, such as "positive," "neutral," "zero," "negative neutral," and "negative." It then makes inferences based on a pre-set "fuzzy rule table" (if the deviation is negative and the rate of change is positive, the output control variable is positive) based on expert experience or extensive experiments. This algorithm then derives fuzzy values ​​for control variables, such as motor speed or direction adjustment. Finally, through a defuzzification process, these fuzzy control variable outputs are converted into precise control commands that directly drive the motor. These control commands, in real time, control the X-axis motion module to fine-tune its speed or position and the Z-axis motion module to compensate for height differences. This ensures that the distance between the line scan camera's lens and the display surface is dynamically and precisely maintained at the optimal imaging focal plane during high-speed scanning. The line scan camera maintains a constant speed throughout its X-axis motion. Combined with its unidirectional scanning mode, this avoids pauses during direction changes, enabling truly high-speed continuous image capture.

[0038] Step 4: As the scanning progresses, the continuous linear image data output by the line array camera are precisely stitched together in sequence to form a complete two-dimensional image, and transmitted to the downstream image processing module for image processing.

[0039] Step 5: After scanning a display screen, the cylinder drives the telescopic expansion plate to retract and reset, and the turntable returns to its initial angle. The robot then directly grabs the image and places it on the conveyor platform (conveyor belt) downstream of the assembly line. It then turns back to grab the next piece to be inspected from the feeding platform and accurately places it in the reset slot. At this time, the line scan camera moves from the left end to the right end position. The line scan camera and the rotating platform are adaptively adjusted using the judgment method described in step 2. That is, when the line scan camera travels from left to right, after it reaches the rightmost end and completes a scan, the rotary motor is controlled to rotate the line scan camera 180 degrees. At the same time, the display screen on the rotating platform is controlled to rotate 180 degrees by the drive component. At this time, when the line scan camera is driven from right to left to perform the next scan, the accuracy of its image stitching can be guaranteed. In this process, the fuzzy PID algorithm of the controller is used to adaptively focus the line scan camera to ensure the quality of the formed image.

[0040] Then, in this way, the linear array camera can scan and capture the display screen as it moves back and forth, ensuring that the device seamlessly enters the next inspection cycle over and over again, realizing fully automatic, continuous, and high-speed image acquisition operations on the production line. The entire process is tightly connected, minimizing non-scanning time and significantly improving overall inspection efficiency.

[0041] The embodiments of the present invention described above do not limit the scope of protection of the present invention. The basic concept of the present invention is that regardless of whether the line scan camera moves forward or backward, the display screen is rotated to align with the scanning direction, ensuring that all images are captured in a uniform direction and that the position corresponds to the positive direction of the line scan camera output terminal. This achieves large-scale, high-resolution, high-quality, online, high-speed imaging. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the claims.

Claims

1. A high-speed online AOI image acquisition device, characterized by: The apparatus comprises a stand, a focusing assembly, and a loading assembly arranged on a base; the focusing assembly comprises a linear array camera, an X-axis moving module, a Z-axis moving module, a rotating module, and a positioning device; the X-axis moving module is laterally fixed to the stand, the Z-axis moving module is vertically mounted on a moving base of the X-axis moving module, the linear array camera is fixed to the rotating module, the rotating module is fixed to a moving base of the Z-axis moving module, and the positioning device is arranged on the stand, the positioning device is used to monitor the position and distance between the linear array camera and the detection target in the X-axis and Z-axis directions, and the positioning device is connected to a controller signal, and the controller drives the linear array camera to move back and forth along the X-axis and Z-axis on the moving module; The object-carrying assembly includes a driving assembly and a rotating platform. The rotating platform is arranged on a base. A slot for placing the detection target is opened on the top of the rotating platform. The driving assembly is arranged below the rotating platform and is used to drive the rotating platform to drive the detection target to rotate 180 degrees so that the collection surface of the detection target always adapts to the unidirectional scanning direction of the linear array camera.

2. The AOI image high-speed online acquisition device according to claim 1, characterized in that: The rotating platform includes a turntable, a telescopic extension plate, a base and a linkage assembly. The turntable is rotatably mounted in the middle of the base through the linkage assembly. The telescopic extension plate is located below the turntable and is connected to the turntable through the linkage assembly. The driving assembly is connected to the telescopic extension plate. When the driving assembly controls the telescopic extension plate to expand or contract laterally, the turntable can be synchronously driven to rotate under the action of the linkage assembly.

3. The AOI image high-speed online acquisition device according to claim 2, characterized in that: The linkage assembly includes a connecting rod, a rotating pin and a column. A column is fixed in the middle of the base, and a rotating arm is rotatably installed between the column and the base. The column is symmetrically provided with grooves, and the rotating pin is fixed to the bottom of the turntable. The bottom of the rotating pin contacts the top surface of the column and can rotate circumferentially on the column; one end of the connecting rod is hinged to the telescopic expansion plate, and the other end is hinged to the end of the rotating arm; a rotating pin and a docking joint are symmetrically fixed at the bottom of the turntable, and the docking joint is adapted to be assembled in the docking sleeve and can move up and down in the docking sleeve; when the telescopic expansion plate expands outward, the turntable can be driven to rotate by the connecting rod to drive the rotating pin to move along the top surface of the column until the rotating pin rotates into the groove, and the turntable rotates 180 degrees and is adapted to be mounted between the two telescopic expansion plates.

4. The AOI image high-speed online acquisition device according to claim 2, characterized in that: The driving assembly includes a cylinder, a connecting seat, a rocker arm, a slider and a guide rail. The guide rail is fixed to the bottom of the base, the slider is slidably installed on the guide rail, and a guide rod is provided on the slider. One end of the rocker arm is hinged to the output end of the cylinder, and the other end is hinged to the guide rod. The cylinder is driven to telescopic movement by the controller, thereby driving the slider to move back and forth horizontally through the rocker arm to control the telescopic expansion plate to extend outward or retract and reset inward.

5. The AOI image high-speed online acquisition device according to claim 1, characterized in that: The positioning device includes a laser sensor and a grating sensor. The laser sensor is located on one side of the linear array camera and is fixed on the rotating module, and is used to detect the distance between the linear array camera and different acquisition positions on the detection target; the grating sensor includes a transmitting end and a receiving end, which are located on the left and right sides of the linear array camera and symmetrically fixed on the stand, and are used to detect the movement distance of the linear array camera along the X-axis.

6. The AOI image high-speed online acquisition device according to claim 5, characterized in that: The laser sensor is located on one side of the linear array camera; the transmitting end and receiving end of the grating sensor are symmetrically fixed on the left and right sides of the X-axis moving module; the laser sensor and the grating sensor transmit the distance signal along the Z axis and the grating signal along the X axis as braking signal input to the controller. The controller is equipped with a fuzzy PID algorithm. After receiving the input signal, it drives the X-axis moving module and the Z-axis moving module to drive the linear array camera to move to the optimal imaging distance, so that it maintains the correct focus, thereby scanning and collecting the touch screen.

7. The AOI image high-speed online acquisition device according to claim 6, characterized in that: When the fuzzy PID algorithm is applied, the Z-axis deviation is obtained through real-time distance measurement by the laser sensor, and the grating ruler synchronously provides the X-axis position of the linear array camera. The fuzzification module converts the above deviation value into a language variable, and then calls a preset fuzzy rule table to infer the fuzzy value of the output control quantity. Finally, the fuzzification is defuzzified to obtain precise motor control instructions to control the X-axis moving module, Z-axis moving module and rotation module to drive the movement of the linear array camera.

8. The AOI image high-speed online acquisition device according to claim 1, characterized in that: It also includes a robot arm, which is located at the front side of the rotating platform and is connected to the controller signal. The robot arm can pick up the detection target on the assembly line conveyor belt and place it in the card slot of the rotating platform.

9. The AOI image high-speed online acquisition device according to claim 1, characterized in that: The base is provided with a guide rail, and the stand is slidably mounted on the base. Under the action of thrust, the stand can move linearly toward the direction of the detection target.

10. A high-speed online acquisition method for AOI images, applied to the high-speed online acquisition device for AOI images according to any one of claims 1 to 9, characterized in that: The following steps are involved: Step 1: The robot grabs the LCM display from the assembly line and places it in the slot on the rotating platform. The controller activates the laser sensor and grating sensor to adjust the line scan camera to its initial position on the left. Step 2: Based on the positive and negative values ​​of the line scan camera's X-axis coordinate position output by the grating sensor, the controller triggers control of the drive cylinder. When the line scan camera is scanning in the forward direction, there is no need to rotate the display screen. When the line scan camera is scanning in the reverse direction, the controller controls the drive cylinder to extend, pushing the swing arm to swing and driving the slider on the guide rail to move horizontally. The slider drives the telescopic expansion plate outward through the guide rod, and at the same time drives the turntable to rotate, so that the display screen acquisition surface is facing the appropriate scanning direction. Step 3: Start the mobile module to control the linear scan camera to move along the X-axis. The laser sensor collects the Z-axis distance deviation between the camera and the display surface in real time, and the grating sensor synchronously feeds back the X-axis displacement signal. The controller dynamically adjusts the position of the linear scan camera using a fuzzy PID algorithm, drives the rotation module to rotate the linear scan camera 180 degrees, and drives the lifting module to adjust the Z-axis height of the linear scan camera to maintain optimal focus throughout the entire process. Step 4: The line scan camera maintains a constant speed and continuously scans in a unidirectional motion until the display screen is completely scanned. The captured line images are stitched into a complete two-dimensional image in real time and transmitted to the downstream image processing module. Step 5: After the scan is completed, the cylinder drives the telescopic expansion plate to retract and reset, and the turntable returns to its initial angle; the robot removes the inspected display screen and places a new target, and the device enters the next inspection cycle, realizing fully automatic and continuous operation of the assembly line.

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