Intelligent control system of OHT overhead crane

Abstract

The present invention discloses an intelligent control system of an OHT overhead crane, and belongs to the technical field of production equipment control. The present invention can conveniently correct the horizontal position of a material carrier by setting a position correction module, so that the screen component below can be within the boundary range of the adsorption area formed by the suction cup array in the material carrier; through the suction cup selection module, according to the position data of the outer contour line of the screen component in the image and the coordinates of each vacuum suction cup on the horizontal plane, the vacuum suction cup required for this grabbing is determined, and the vacuum suction cup at the corresponding position can be selected according to the needs for subsequent adsorption work, so that it can be suitable for the transportation of screen components of different specifications or types.

Description

Technical Field

[0001] The present invention relates to the technical field of production equipment control, and in particular to an intelligent control system of an OHT overhead crane. Background Art

[0002] OHT overhead crane is an automated transportation system, the full name of which is Overhead Hoist Transport, which literally means overhead lifting conveyor. It is a transportation tool that runs on an overhead track and has lifting and transmission functions. OHT overhead crane directly enters the loading and unloading port of storage equipment or process equipment through a belt-driven lifting component to realize the transportation of materials within the process area and between process areas or factories. This system is widely used in semiconductor production lines. Through the tracks laid in the air, the trolley walks on the track to automatically transport production materials and load and unload equipment. The characteristics of OHT overhead crane include high-altitude operation (for indoor environments, that is, ceilings), lifting action (lifting or placing from the ground, with telescopic, lifting and other mechanisms), and transmission action (moving on the track, with motors, drives, rollers and other mechanisms). The composition of OHT overhead crane generally includes trolleys, guide rail mechanisms, material carriers and non-contact power supply systems. This system greatly improves the overall production process by improving material transportation efficiency, reducing labor costs and reducing pollution risks.

[0003] In the production process of LED screens, OHT overhead cranes are often needed to transport screen components. The material carriers of existing OHT overhead cranes are mostly fixed structures. When transporting screen components, the application range is not wide enough, and it is impossible to control the material carriers to be suitable for the transportation of screen components of different specifications or types. Therefore, an intelligent control system for OHT overhead cranes is proposed. Summary of the invention

[0004] The technical problem to be solved by the present invention is: how to solve the problem that the material carriers of existing OHT overhead cranes are mostly fixed structures, which have a narrow scope of application when transporting screen components, and cannot be suitable for the transportation of screen components of different specifications or types by controlling the material carriers. An intelligent control system for an OHT overhead crane is provided.

[0005] The present invention solves the above technical problems through the following technical solutions. The present invention includes a position correction module, a suction cup coordinate determination module, a suction cup selection module and an adsorption module;

[0006] The position correction module is used to obtain a first image and correct the horizontal position of the material carrier according to the first image after the trolley reaches the initial position;

[0007] The suction cup coordinate determination module is used to determine the coordinates of each vacuum suction cup on the horizontal plane after the horizontal position calibration of the material carrier is completed;

[0008] The suction cup selection module is used to obtain the second image and determine the vacuum suction cup required for this grasping according to the second image after the coordinates of each vacuum suction cup on the horizontal plane are determined;

[0009] The adsorption module is used to drive each required vacuum suction cup to synchronously descend to a set position according to the determined vacuum suction cup required for this grabbing, to perform the adsorption work of the screen assembly, and then realize the grabbing of the screen assembly.

[0010] Furthermore, the position correction module includes a first image acquisition unit, a first image preprocessing unit, a first target recognition unit, an adjustment distance calculation unit and a horizontal position adjustment unit; the first image acquisition unit is used to use a camera set on the material carrier to shoot the screen component below after the trolley reaches the initial position to obtain a first image; the first image preprocessing unit is used to preprocess the first image; the first target recognition unit is used to use a trained target detection model to recognize the preprocessed first image, and obtain the screen component detection frame and its position information in the image; the adjustment distance calculation unit is used to calculate and obtain the two-axis distance difference of the material carrier on the horizontal plane according to the position information of the screen component detection frame in the image; the horizontal position adjustment unit is used to use the guide rail mechanism of the OHT overhead crane and adjust the horizontal position of the material carrier according to the two-axis distance difference; wherein, the optical axis of the camera is perpendicular to the horizontal plane, and shoots vertically downward, and the position information of the screen component detection frame in the image is the coordinates of the upper left corner and lower right corner of the screen component detection frame in the preprocessed first image.

[0011] Furthermore, in the adjustment distance calculation unit, the specific processing process is as follows:

[0012] S11: acquiring the coordinates of the center point of the screen component detection frame according to the coordinates of the upper left corner point and the lower right corner point of the screen component detection frame in the preprocessed first image, where the center point is recorded as C1;

[0013] S12: in the preprocessed first image, obtaining the coordinates of the center point of the image, the center point is recorded as C0;

[0014] S13: Project the line segment C0C1 between the center point C0 of the image and the center point C1 of the screen component detection frame onto the x-axis and y-axis of the image coordinate system respectively, and obtain the projection line segment on the x-axis and y-axis and the coordinates of each point on the projection line segment. The projection line segment on the x-axis and y-axis is recorded as Lx and Ly respectively.

[0015] S14: According to the pre-calibrated coordinate transformation relationship between the world coordinate system and the image coordinate system, the coordinates of each point on the projection line segments Lx and Ly are transformed to the world coordinate system, and the actual length values ​​of the projection lengths Lx and Ly on the X-axis and Y-axis in the world coordinate system are calculated and recorded as DisX and DisY, that is, the distance difference between the two axes of the material carrier on the horizontal plane is obtained.

[0016] Furthermore, in the horizontal position adjustment unit, according to the actual length values ​​DisX and DisY of the X-axis and the Y-axis in the world coordinate system, the horizontal position of the material carrier is adjusted using the guide rail mechanism and the trolley of the OHT overhead crane. After the adjustment, the image center point C0 of the first image coincides with the center point C1 of the screen component detection frame.

[0017] Furthermore, the specific processing process of the suction cup coordinate determination module is as follows:

[0018] S21: After the horizontal position of the material carrier is calibrated, the coordinates of the camera in the world coordinates are recorded as (Xs, Ys, Zs). The coordinates of the center point of the lower end surface of the camera in the world coordinates are used as the coordinates of the camera in the world coordinates. The center point of the lower end surface of the camera is located on the axis of the camera.

[0019] S22: According to the design data, the actual distance di and angle θi between the axis of each vacuum suction cup and the axis of the camera in the horizontal plane are obtained. According to the distance di and the angle θi and the coordinates of the camera in the world coordinate system (Xs, Ys, Zs), the X-axis and Y-axis coordinate values ​​of the projection point of the axis of each vacuum suction cup in the horizontal plane in the world coordinate system are calculated and recorded as (Xi, Yi). (Xi, Yi) is the coordinate of each vacuum suction cup in the horizontal plane, where i is the number of the vacuum suction cup, indicating the i-th vacuum suction cup.

[0020] Furthermore, the suction cup selection module includes a second image acquisition unit, a second image preprocessing unit, a second target recognition unit, and a vacuum suction cup determination unit; the second image acquisition unit is used to use the camera set on the material carrier to shoot the screen assembly below again to obtain a second image; the second image preprocessing unit is used to preprocess the second image; the second target recognition unit is used to use the trained target detection model to recognize the preprocessed second image, and obtain the screen assembly detection frame and its position information in the image; the vacuum suction cup determination unit is used to perform contour detection on the screen assembly in the screen assembly detection frame, obtain the position data of the outer contour line of the screen assembly in the image, and then determine the vacuum suction cup required for this grabbing according to the position data of the outer contour line of the screen assembly in the image and the coordinates of each vacuum suction cup on the horizontal plane; the optical axis of the camera is perpendicular to the horizontal plane, and shoots vertically downward, and the position information of the screen assembly detection frame in the image is the coordinates of the upper left corner and lower right corner of the screen assembly detection frame in the preprocessed second image.

[0021] Furthermore, in the vacuum chuck determination unit, the specific processing process is as follows:

[0022] S31: using the contour detection function in OpenCV to perform contour detection on the screen component in the screen component detection frame, and obtaining the coordinates of each point on the outer contour line of the screen component in the image, that is, the position data of the outer contour line of the screen component in the image;

[0023] S32: according to the coordinate transformation relationship between the pre-calibrated world coordinate system and the image coordinate system, transform the coordinates of each point on the outer contour line of the screen component in the image into the world coordinate system to obtain the coordinates of each point on the actual outer contour line in the world coordinate system;

[0024] S33: Projecting each point on the actual outer contour line in the world coordinate system onto the horizontal plane, obtaining the X-axis and Y-axis coordinate values ​​of each projection point on the horizontal plane in the world coordinate system, recorded as (Xk, Yk), where k is the number of the projection point, indicating the projection point on the k-th horizontal plane;

[0025] S34: Obtaining the actual outer contour line projection area A0 on the horizontal plane according to the X-axis and Y-axis coordinate values ​​of each projection point on the horizontal plane in the world coordinate system;

[0026] S35: using the correction factor Q to correct the coordinates of each point on the actual outer contour line projection area A0, when correcting, the coordinate value of each point is multiplied by the correction factor Q to obtain the corrected coordinate value of each point, and then obtain the corrected outer contour line projection area A1;

[0027] S36: The coordinates (Xi, Yi) of each vacuum suction cup on the horizontal plane are traversed and judged. When the coordinates fall within the corrected outer contour line projection area A1, the number of the corresponding vacuum suction cup is retained. The numbers of all the retained vacuum suction cups form a set T. The set T includes the numbers of the vacuum suction cups required for this grabbing. The vacuum suction cups outside the set T will not perform subsequent descending and adsorption actions.

[0028] Furthermore, the x-axis and y-axis in the image coordinate systems of the first image and the second image are parallel to the X-axis and Y-axis in the world coordinate system, the x-axis and y-axis in the image coordinate system and the X-axis and Y-axis in the world coordinate system are all in the horizontal plane, and the Z-axis in the world coordinate system is in the vertical direction.

[0029] Compared with the prior art, the present invention has the following advantages: the intelligent control system of the OHT overhead crane can conveniently correct the horizontal position of the material carrier through the set position correction module, so that the screen component below can be within the boundary range of the adsorption area formed by the suction cup array in the material carrier; through the set suction cup selection module, the vacuum suction cup required for this grabbing is determined according to the position data of the outer contour line of the screen component in the image and the coordinates of each vacuum suction cup on the horizontal plane, and the vacuum suction cup at the corresponding position can be selected according to the needs for subsequent adsorption work, so that it can be suitable for the transportation of screen components of different specifications or types. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Schematic diagram of the structure of the intelligent control system of the OHT overhead travelling crane in an embodiment of the present invention;

[0031] Figure 2 It is a schematic diagram of the partial structure of the OHT overhead travelling crane in an embodiment of the present invention. DETAILED DESCRIPTION

[0032] The following is a detailed description of an embodiment of the present invention. This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiment.

[0033] like Figure 1 As shown, this embodiment provides a technical solution: an intelligent control system of an OHT overhead travelling crane, including a position correction module, a suction cup coordinate determination module, a suction cup selection module and an adsorption module;

[0034] In this embodiment, the position correction module is used to correct the horizontal position of the material carrier, so that the lower screen assembly can be within the boundary range of the adsorption area formed by the suction cup array in the material carrier;

[0035] More specifically, the position correction module includes a first image acquisition unit, a first image preprocessing unit, a first target recognition unit, an adjustment distance calculation unit and a horizontal position adjustment unit; the first image acquisition unit is used to use a camera arranged on the material carrier to shoot the screen component below after the trolley reaches the initial position to obtain a first image; the first image preprocessing unit is used to preprocess the first image to improve the image quality; the first target recognition unit is used to use a trained target detection model to identify the preprocessed first image, obtain the screen component detection frame and its position information in the image; the adjustment distance calculation unit is used to calculate and obtain the two-axis distance difference of the material carrier on the horizontal plane according to the position information of the screen component detection frame in the image; the horizontal position adjustment unit is used to use the guide rail mechanism of the OHT overhead crane and adjust the horizontal position of the material carrier according to the two-axis distance difference.

[0036] More specifically, in the first image acquisition unit, the optical axis of the camera is perpendicular to the horizontal plane, and the camera shoots vertically downward, so that the first image captured includes the complete screen assembly.

[0037] More specifically, in the first image preprocessing unit, the preprocessing methods include but are not limited to image denoising and image enhancement processing, which can effectively reduce the noise in the image and improve the brightness and contrast of the image, thereby improving the overall quality of the image and facilitating improving the accuracy of subsequent target recognition.

[0038] More specifically, in the first target recognition unit, the target detection model is trained based on the SSD detection network.

[0039] More specifically, in the first target recognition unit, the position information of the screen component detection frame in the image is the coordinates of the upper left corner and the lower right corner of the screen component detection frame in the preprocessed first image.

[0040] More specifically, in the adjustment distance calculation unit, the specific processing process is as follows:

[0041] S11: acquiring the coordinates of the center point of the screen component detection frame according to the coordinates of the upper left corner point and the lower right corner point of the screen component detection frame in the preprocessed first image, where the center point is recorded as C1;

[0042] S12: in the preprocessed first image, obtaining the coordinates of the center point of the image, the center point is recorded as C0;

[0043] S13: Project the line segment C0C1 between the center point C0 of the image and the center point C1 of the screen component detection frame onto the x-axis and y-axis of the image coordinate system respectively, and obtain the projection line segment on the x-axis and y-axis and the coordinates of each point on the projection line segment. The projection line segment on the x-axis and y-axis is recorded as Lx and Ly respectively.

[0044] S14: According to the pre-calibrated coordinate transformation relationship between the world coordinate system and the image coordinate system, the coordinates of each point on the projection line segments Lx and Ly are transformed to the world coordinate system, and the actual length values ​​of the projection lengths Lx and Ly on the X-axis and Y-axis in the world coordinate system are calculated and recorded as DisX and DisY, that is, the distance difference between the two axes of the material carrier on the horizontal plane is obtained.

[0045] It should be noted that the x-axis and y-axis in the image coordinate system of the first image are parallel to the X-axis and Y-axis in the world coordinate system in this embodiment, the x-axis and y-axis in the image coordinate system and the X-axis and Y-axis in the world coordinate system are all in the horizontal plane, and the Z-axis in the world coordinate system is in the vertical direction.

[0046] More specifically, in the horizontal position adjustment unit, according to the actual length values ​​DisX and DisY of the X-axis and the Y-axis in the world coordinate system, the horizontal position of the material carrier is adjusted using the guide rail mechanism of the OHT overhead crane and the trolley, and after the adjustment, the image center point C0 of the first image coincides with the center point C1 of the screen component detection frame. The guide rail mechanism of the OHT overhead crane includes mutually perpendicular X-axis linear guide rails and Y-axis linear guide rails (horizontally arranged), and the Y-axis linear guide rail can move along the X-axis linear guide rail through a motor-driven transmission structure (transmission wheels and other components), and the trolley can move on the Y-axis linear guide rail, thereby driving the material carrier and the lifting mechanism to move in two axes in the horizontal plane, wherein the trolley is used to adjust the position on the Y-axis, and the Y-axis linear guide rail is used to adjust the position on the X-axis.

[0047] In this embodiment, the suction cup coordinate determination module is used to determine the coordinates of each vacuum suction cup on the horizontal plane after the horizontal position calibration of the material carrier is completed;

[0048] More specifically, the specific processing process of the suction cup coordinate determination module is as follows:

[0049] S21: After the horizontal position of the material carrier is calibrated, the coordinates of the camera in the world coordinates are recorded as (Xs, Ys, Zs). The coordinates of the center point of the lower end surface of the camera in the world coordinates are used as the coordinates of the camera in the world coordinates. The center point of the lower end surface of the camera is located on the axis of the camera; the axis also coincides with its optical axis.

[0050] S22: According to the design data, the actual distance di and angle θi between the axis of each vacuum suction cup and the axis of the camera in the horizontal plane are obtained. According to the distance di and the angle θi and the coordinates of the camera in the world coordinate system (Xs, Ys, Zs), the X-axis and Y-axis coordinate values ​​of the projection point of the axis of each vacuum suction cup in the horizontal plane in the world coordinate system are calculated and recorded as (Xi, Yi). (Xi, Yi) is the coordinate of each vacuum suction cup in the horizontal plane, where i is the number of the vacuum suction cup, indicating the i-th vacuum suction cup.

[0051] In this embodiment, the suction cup selection module is used to obtain a second image and determine the vacuum suction cup required for this grabbing according to the second image after the coordinates of each vacuum suction cup on the horizontal plane are determined; it can select the vacuum suction cup at the corresponding position according to the screen components of different specifications (sizes) or types (shapes) for subsequent adsorption work, which greatly improves the application scope of the OHT overhead crane.

[0052] More specifically, the suction cup selection module includes a second image acquisition unit, a second image preprocessing unit, a second target recognition unit, and a vacuum suction cup determination unit; the second image acquisition unit is used to use the camera set on the material carrier to shoot the screen assembly below again to obtain a second image; the second image preprocessing unit is used to preprocess the second image to improve the quality of the image; the second target recognition unit is used to use the trained target detection model to identify the preprocessed second image, obtain the screen component detection frame and its position information in the image, the position information of the screen component detection frame in the image, that is, the coordinates of the upper left corner and lower right corner of the screen component detection frame in the preprocessed second image; the vacuum suction cup determination unit is used to perform contour detection on the screen component in the screen component detection frame, obtain the position data of the outer contour line of the screen component in the image, and then determine the vacuum suction cup required for this grasping according to the position data of the outer contour line of the screen component in the image and the coordinates of each vacuum suction cup on the horizontal plane.

[0053] To be more specific, the second image acquisition unit, the second image preprocessing unit, and the second target recognition unit have the same working principles as the corresponding first image acquisition unit, the first image preprocessing unit, and the first target recognition unit, and the devices and models they use are the same, which will not be repeated here.

[0054] More specifically, in the vacuum chuck determination unit, the specific processing process is as follows:

[0055] S31: using the contour detection function in OpenCV to perform contour detection on the screen component in the screen component detection frame, and obtaining the coordinates of each point on the outer contour line of the screen component in the image, that is, the position data of the outer contour line of the screen component in the image;

[0056] S32: according to the coordinate transformation relationship between the pre-calibrated world coordinate system and the image coordinate system, transform the coordinates of each point on the outer contour line of the screen component in the image into the world coordinate system to obtain the coordinates of each point on the actual outer contour line in the world coordinate system;

[0057] S33: Projecting each point on the actual outer contour line in the world coordinate system onto the horizontal plane, obtaining the X-axis and Y-axis coordinate values ​​of each projection point on the horizontal plane in the world coordinate system, recorded as (Xk, Yk), where k is the number of the projection point, indicating the projection point on the k-th horizontal plane, k<i;

[0058] S34: Obtaining the actual outer contour line projection area A0 on the horizontal plane according to the X-axis and Y-axis coordinate values ​​of each projection point on the horizontal plane in the world coordinate system;

[0059] S35: using the correction factor Q to correct the coordinates of each point on the actual outer contour line projection area A0, when correcting, the coordinate value of each point is multiplied by the correction factor Q to obtain the corrected coordinate value of each point, and then obtain the corrected outer contour line projection area A1;

[0060] In this embodiment, the value range of Q is 0.8 to 0.9, which is used to ensure that each vacuum suction cup required for this grasping can be completely adsorbed on the screen assembly;

[0061] S36: The coordinates (Xi, Yi) of each vacuum suction cup on the horizontal plane are traversed and judged. When the coordinates fall within the corrected outer contour line projection area A1, the number of the corresponding vacuum suction cup is retained. The numbers of all the retained vacuum suction cups form a set T, and the set T includes the numbers of the vacuum suction cups required for this grasping.

[0062] In this embodiment, the adsorption module is used to drive each required vacuum suction cup to synchronously descend to a set position according to the determined vacuum suction cup required for this grabbing, and adsorb the screen assembly to complete the subsequent transportation work. The vacuum suction cups outside the set T do not perform subsequent actions (neither descend nor adsorb) in this adsorption work.

[0063] like Figure 2As shown, an OHT overhead crane is also provided in this embodiment, including a guide rail mechanism, a trolley 1, a lifting mechanism 2 and a material carrier; the guide rail mechanism includes an X-axis linear guide 41, a Y-axis linear guide 42 and corresponding guide rails, the Y-axis linear guide 42 is connected to the X-axis linear guide 41, the X-axis linear guide 41, the Y-axis linear guide 42, the Y-axis linear guide 42 is driven by a motor to drive a transmission structure (transmission wheel and other components) to move along the X-axis linear guide 41, the trolley 1 is driven by a motor to drive a transmission structure (transmission gear wheel and other components) to move on the Y-axis linear guide 42, and then drive The animal material carrier and the lifting mechanism perform two-axis movement in the horizontal plane; the trolley 1 is arranged on the Y-axis linear guide 42, and the trolley 1 is connected to the material carrier through the lifting mechanism 2, and the material carrier includes a shell 31 and a plurality of vertically arranged vacuum suction cup assemblies (arranged in a rectangular array as a whole); the plurality of vertically arranged vacuum suction cup assemblies are fixedly arranged inside the shell 31, and the vacuum suction cup assembly includes a lifting part 321 and a vacuum suction cup 322, and the vacuum suction cup 322 is arranged at the lower end of the lifting part 321, and the adsorption and release actions of the vacuum suction cup 322 are controlled by an external vacuum pump.

[0064] More specifically, the lifting mechanism 2 is a first lifting cylinder.

[0065] More specifically, a guide plate 311 is fixedly disposed at the lower end of the housing 31 , the lifting portion 321 is a second lifting cylinder, and a plurality of guide holes are disposed on the guide plate 311 for guiding the cylinder column of the second lifting cylinder. The camera 5 is mounted at the center of the guide plate 311 .

[0066] It should be noted that, in this embodiment, the screen assembly 6 is placed on the operating platform 7, and the screen assembly 6 is generally square (planar structure), and of course, it can also be round (planar structure) and other shapes. The maximum length between any two points on the edge of the screen assembly 6 is less than the minimum length between any two points on the boundary of the adsorption area formed by the vacuum suction cup array.

[0067] To summarize, the intelligent control system of the OHT overhead crane in the above-mentioned embodiment can conveniently correct the horizontal position of the material carrier through the set position correction module, so that the screen assembly below can be within the boundary of the adsorption area formed by the suction cup array in the material carrier; through the set suction cup selection module, according to the position data of the outer contour line of the screen assembly in the image and the coordinates of each vacuum suction cup on the horizontal plane, the vacuum suction cup required for this grabbing is determined, and the vacuum suction cup at the corresponding position can be selected as needed for subsequent adsorption work, so that it can be suitable for the transportation of screen assemblies of different specifications or types.

[0068] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0069] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0070] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. The intelligent control system of OHT overhead crane is characterized by: include: Position correction module, suction cup coordinate determination module, suction cup selection module and adsorption module; The position correction module is used to obtain a first image and correct the horizontal position of the material carrier according to the first image after the trolley reaches the initial position; The suction cup coordinate determination module is used to determine the coordinates of each vacuum suction cup on the horizontal plane after the horizontal position calibration of the material carrier is completed; The suction cup selection module is used to obtain the second image and determine the vacuum suction cup required for this grasping according to the second image after the coordinates of each vacuum suction cup on the horizontal plane are determined; The suction cup selection module includes a second image acquisition unit, a second image preprocessing unit, a second target recognition unit, and a vacuum suction cup determination unit; the second image acquisition unit is used to use a camera provided on the material carrier to photograph the screen assembly below again to obtain a second image; the second image preprocessing unit is used to preprocess the second image; The second target recognition unit is used to use the trained target detection model to recognize the preprocessed second image, and obtain the screen component detection frame and its position information in the image; the vacuum suction cup determination unit is used to perform contour detection on the screen component in the screen component detection frame, obtain the position data of the outer contour line of the screen component in the image, and then determine the vacuum suction cup required for this grasping according to the position data of the outer contour line of the screen component in the image and the coordinates of each vacuum suction cup on the horizontal plane; the optical axis of the camera is perpendicular to the horizontal plane, and the camera shoots vertically downward, and the position information of the screen component detection frame in the image is the coordinates of the upper left corner point and the lower right corner point of the screen component detection frame in the preprocessed second image; In the vacuum cup determination unit, the specific processing process is as follows: S31: using the contour detection function in OpenCV to perform contour detection on the screen component in the screen component detection frame, and obtaining the coordinates of each point on the outer contour line of the screen component in the image, that is, the position data of the outer contour line of the screen component in the image; S32: according to the coordinate transformation relationship between the pre-calibrated world coordinate system and the image coordinate system, transform the coordinates of each point on the outer contour line of the screen component in the image into the world coordinate system to obtain the coordinates of each point on the actual outer contour line in the world coordinate system; S33: Projecting each point on the actual outer contour line in the world coordinate system onto the horizontal plane, obtaining the X-axis and Y-axis coordinate values ​​of each projection point on the horizontal plane in the world coordinate system, recorded as (Xk, Yk), where k is the number of the projection point, indicating the projection point on the k-th horizontal plane; S34: Obtaining the actual outer contour line projection area A0 on the horizontal plane according to the X-axis and Y-axis coordinate values ​​of each projection point on the horizontal plane in the world coordinate system; S35: using the correction factor Q to correct the coordinates of each point on the actual outer contour line projection area A0, when correcting, the coordinate value of each point is multiplied by the correction factor Q to obtain the corrected coordinate value of each point, and then obtain the corrected outer contour line projection area A1; S36: traverse and judge the coordinates (Xi, Yi) of each vacuum suction cup on the horizontal plane. When the coordinates fall within the corrected outer contour line projection area A1, the number of the corresponding vacuum suction cup is retained. The numbers of all the retained vacuum suction cups form a set T. The set T includes the numbers of the vacuum suction cups required for this grabbing. The vacuum suction cups outside the set T do not perform subsequent descending and adsorption actions. The adsorption module is used to drive each required vacuum suction cup to synchronously descend to a set position according to the determined vacuum suction cup required for this grabbing, to perform the adsorption work of the screen assembly, and then realize the grabbing of the screen assembly.

2. The intelligent control system of the OHT overhead travelling crane according to claim 1 is characterized in that: The position correction module includes a first image acquisition unit, a first image preprocessing unit, a first target recognition unit, an adjustment distance calculation unit and a horizontal position adjustment unit; the first image acquisition unit is used to use a camera provided on the material carrier to shoot the screen assembly below after the trolley reaches the initial position to acquire a first image; The first image preprocessing unit is used to preprocess the first image; The first target recognition unit is used to use the trained target detection model to identify the preprocessed first image, and obtain the screen component detection frame and its position information in the image; the adjustment distance calculation unit is used to calculate and obtain the two-axis distance difference of the material carrier on the horizontal plane according to the position information of the screen component detection frame in the image; the horizontal position adjustment unit is used to use the guide rail mechanism of the OHT overhead crane and adjust the horizontal position of the material carrier according to the two-axis distance difference; wherein, the optical axis of the camera is perpendicular to the horizontal plane, and shoots vertically downward, and the position information of the screen component detection frame in the image is the coordinates of the upper left corner and the lower right corner of the screen component detection frame in the preprocessed first image.

3. The intelligent control system of the OHT overhead travelling crane according to claim 2 is characterized in that: In the adjustment distance calculation unit, the specific processing process is as follows: S11: acquiring the coordinates of the center point of the screen component detection frame according to the coordinates of the upper left corner point and the lower right corner point of the screen component detection frame in the preprocessed first image, where the center point is recorded as C1; S12: in the preprocessed first image, obtaining the coordinates of the center point of the image, the center point is recorded as C0; S13: Project the line segment C0C1 between the center point C0 of the image and the center point C1 of the screen component detection frame onto the x-axis and y-axis of the image coordinate system respectively, and obtain the projection line segment on the x-axis and y-axis and the coordinates of each point on the projection line segment. The projection line segment on the x-axis and y-axis is recorded as Lx and Ly respectively. S14: According to the pre-calibrated coordinate transformation relationship between the world coordinate system and the image coordinate system, the coordinates of each point on the projection line segments Lx and Ly are transformed to the world coordinate system, and the actual length values ​​of the projection lengths Lx and Ly on the X-axis and Y-axis in the world coordinate system are calculated and recorded as DisX and DisY, that is, the distance difference between the two axes of the material carrier on the horizontal plane is obtained.

4. The intelligent control system of the OHT overhead travelling crane according to claim 3 is characterized in that: In the horizontal position adjustment unit, the horizontal position of the material carrier is adjusted using the guide rail mechanism and the trolley of the OHT overhead crane according to the actual length values ​​DisX and DisY of the X-axis and the Y-axis in the world coordinate system. After the adjustment, the image center point C0 of the first image coincides with the center point C1 of the screen component detection frame.

5. The intelligent control system of the OHT overhead travelling crane according to claim 1 or 4, characterized in that: The specific processing process of the suction cup coordinate determination module is as follows: S21: After the horizontal position of the material carrier is calibrated, the coordinates of the camera in the world coordinates are recorded as (Xs, Ys, Zs). The coordinates of the center point of the lower end surface of the camera in the world coordinates are used as the coordinates of the camera in the world coordinates. The center point of the lower end surface of the camera is located on the axis of the camera. S22: According to the design data, the actual distance di and angle θi between the axis of each vacuum suction cup and the axis of the camera in the horizontal plane are obtained. According to the distance di and the angle θi and the coordinates of the camera in the world coordinate system (Xs, Ys, Zs), the X-axis and Y-axis coordinate values ​​of the projection point of the axis of each vacuum suction cup in the horizontal plane in the world coordinate system are calculated and recorded as (Xi, Yi). (Xi, Yi) is the coordinate of each vacuum suction cup in the horizontal plane, where i is the number of the vacuum suction cup, indicating the i-th vacuum suction cup.

6. The intelligent control system of the OHT overhead crane according to claim 1 is characterized in that: The x-axis and y-axis in the image coordinate system of the first image and the second image are parallel to the X-axis and Y-axis in the world coordinate system. The x-axis and y-axis in the image coordinate system and the X-axis and Y-axis in the world coordinate system are all in the horizontal plane, and the Z-axis in the world coordinate system is in the vertical direction.

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