A lateral positioning system and method for the trolley of a container tire crane

Abstract

The present invention discloses a lateral positioning system for the trolley of a container tire crane, comprising: a reference plate provided on one side of the straight driving path of the trolley of the tire crane; a target tracking mechanism provided on the trolley of the tire crane and on the same side as the reference plate; an industrial camera provided on the target tracking mechanism, with the lens of the industrial camera facing the reference plate; and an industrial computer provided in the electrical room of the trolley of the tire crane and establishing communication with the target tracking mechanism and the industrial camera through a TCP / IP network. The present invention also discloses a method for lateral positioning of the trolley of a container tire crane. The present invention can solve the problem of lateral positioning of the trolley during the driving operation of the tire crane, that is, the position deviation and the orientation angle deviation of the trolley relative to the driving reference line can be obtained.

Description

Technical Field

[0001] The present invention relates to an on-vehicle sensor positioning system, and more particularly, to a lateral positioning system and method for the trolley of a container tire crane. Background Art

[0002] A container tire crane, also known as a rubber-tired gantry crane, is the most widely used container crane in the inner yard of a container terminal. Its main function is to transport and load / unload standard containers, that is, to stack the working containers on the transport vehicle at the specified position in the terminal yard according to the rules formulated by the terminal, or to load the working containers in the yard onto the transport vehicle, or to stack the working containers in the yard at another specified position, thereby completing the transportation, control and management of the containers. As one of the key technical equipment for realizing the unmanned operation of a container terminal, the automation level of an automated tire crane directly affects the operation efficiency of an automated terminal.

[0003] Currently, the rapid development of container freight has placed increasingly high demands on the loading and unloading efficiency of tire cranes. However, due to the high-density stacking of containers in the yard, the driving space of the trolley of the tire crane is restricted. Especially for tire cranes using the "oil-to-electricity conversion" technology, in order to adapt to the rigid trolley wire, the lateral displacement during straight-line driving cannot exceed 50 cm. Since the trolley of the tire crane has no fixed driving track, to avoid collisions with containers or vehicles, the driver needs to manually correct the deviation for a long time with his head down in the driver's cab about 20 m above the ground. When the stacking height of containers in the yard is relatively high, especially during night operations, it is very difficult for the driver to clearly see the reference line for the trolley of the tire crane to drive. Slight carelessness may lead to collision accidents. Even if no collision accident occurs after the trolley deviates, it is often necessary to repeatedly drive to re-adjust the position and attitude of the huge trolley of the tire crane, which increases the operation time, operation fuel consumption and tire wear of the tire crane. Therefore, researching the automatic driving technology of the trolley of the tire crane has become an important way to solve the above problems, and the lateral positioning system and method for the trolley of the tire crane are one of the important topics among them.

[0004] At present, the existing lateral positioning methods for the trolley of a rubber-tyred gantry crane mainly include: satellite positioning method based on differential signals, magnetic positioning method based on buried detection bodies on the ground, machine vision positioning method based on ground painting and image recognition, and light wave ranging positioning method based on laser, ultrasonic or infrared ranging. Among them, the satellite positioning system based on differential signals has high costs and poor stability. The positioning accuracy is often affected by obstacles such as weather, cranes, containers, and lighthouses, resulting in signal blind spots and short-period jumps, and it has serious limitations in the application and promotion at container terminals. The machine vision positioning system based on ground painting and image recognition cannot meet the requirements of all-weather operation in the yard because its reference line is easily contaminated, which limits its application and promotion. The magnetic positioning system based on buried detection bodies on the ground requires civil engineering on the yard ground, and the system is also interfered by metal fragments often scattered on the ground, and has relatively high requirements for the application scenario. The positioning system based on laser, ultrasonic or infrared ranging needs to rely on actual reference reflectors for positioning measurement. This system has relatively high requirements for the reflection ability of the reflectors, and is seriously interfered by external light, etc., and sometimes it is difficult to correctly reflect the actual position of the equipment. Summary of the Invention

[0005] Aiming at the above-mentioned defects existing in the prior art, the purpose of the present invention is to provide a lateral positioning system and method for the trolley of a container rubber-tyred gantry crane, which can solve the problem of lateral positioning of the trolley during the driving operation of the rubber-tyred gantry crane, that is, the position deviation and the orientation angle deviation of the trolley relative to the driving reference line can be obtained.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] On the one hand, a lateral positioning system for the trolley of a container rubber-tyred gantry crane includes:

[0008] A reference plate, which is arranged on one side of the straight driving road of the trolley of the rubber-tyred gantry crane;

[0009] A target tracking mechanism, which is arranged on the trolley of the rubber-tyred gantry crane and is on the same side as the reference plate;

[0010] An industrial camera, which is arranged on the target tracking mechanism, and the lens of the industrial camera faces the reference plate;

[0011] An industrial computer, which is arranged in the electrical room of the trolley of the rubber-tyred gantry crane and communicates with the target tracking mechanism and the industrial camera through a TCP / IP network.

[0012] Preferably, linear markings are respectively arranged on both side edges in the length direction of the reference plate, including an upper marking and a lower marking arranged in parallel;

[0013] The colors of the upper marking and the lower marking are different from the color of the reference plate.

[0014] Preferably, the reference plate is arranged on one side of the straight driving path of the gantry crane of the container crane through a fixed support.

[0015] Preferably, a guide rail perpendicular to the ground direction and a slider moving up and down along the guide rail are provided on the target tracking mechanism;

[0016] The industrial camera is arranged on the slider.

[0017] Preferably, an image sensor and a lighting device are also equipped on the industrial camera.

[0018] Preferably, the industrial camera adopts an industrial color camera with a resolution of 1280×720, and the focal length of the lens is 8 mm.

[0019] On the other hand, a method for lateral positioning of the gantry crane of the container crane uses the lateral positioning system of the gantry crane of the container crane to execute the target tracking process and the lateral positioning process of the gantry crane of the container crane based on machine vision to obtain the lateral positioning result of the gantry crane of the container crane.

[0020] Preferably, the target tracking process specifically includes the following steps:

[0021] S1. Obtain the images of the upper mark and the lower mark on the reference plate in the industrial camera;

[0022] S2. Combine the internal parameter information in the industrial camera, and extract the pixel points {(u up , v up ) i}(i = 1, 2, …) and {(u down , v down ) i}(i = 1, 2, …) of the upper mark and the lower mark in the image coordinates from the images;

[0023] S3. Combine the distance d between the upper mark and the lower mark and {(u up , v up ) i}(i = 1, 2, …), {(u down , v down ) i}(i = 1, 2, …), and calculate the projection value of the point O c on the O w Z w axis, that is, the height value h c→w relative to the reference plate;

[0024] S4. Transmit the height value h c→w to the target tracking mechanism;

[0025] S5. The target tracking mechanism controls the slider to displace in the opposite direction by h c→w , so as to reach point O c and point O w maintain at the same height.

[0026] Preferably, the lateral positioning process of the RTG crane based on machine vision specifically includes the following steps:

[0027] Step 1. Calibrate the external parameters of the industrial camera to obtain the transformation relationship T c X c Y c Z c between the camera coordinate system O r X r Y r Z r and the vehicle body coordinate system O c→r ;

[0028] Step 2. Obtain the images of the upper identifier and the lower identifier on the reference board in the industrial camera;

[0029] Step 3. Combine the internal parameter information in the industrial camera to extract the pixel points {(u up , v up ) i}(i = 1, 2,...) and {(u down , v down ) i}(i = 1, 2,...) of the upper identifier and the lower identifier in the image coordinates;

[0030] Step 4. Combine the distance d between the upper identifier and the lower identifier and {(u up , v up ) i}(i = 1, 2,...), {(u down , v down ) i}(i = 1, 2,...) to calculate the distance value d r between point O w X w axis and O r→w , and the angle θ r X r axis and O w X w axis; r→w ;

[0031] Step 5. Use the camera coordinate system O c X c Y c Z c and the vehicle body coordinate system Or X r Y r Z r The conversion relationship T between c→r , calculate the point O r and O w X w The distance value d between the axes r→w , and O r X r The angle θ between the axis and O w X w The angle θ between the axes r→w ;

[0032] Step 6, output the lateral position and attitude information of the gantry crane of the rubber-tyred gantry crane.

[0033] A lateral positioning system and method for the gantry crane of a rubber-tyred gantry crane provided by the present invention can solve the problem of lateral positioning of the gantry crane during the driving operation, that is, the position deviation and the orientation angle deviation of the gantry crane relative to the driving reference line can be obtained. These detection information can provide information basis for the automatic driving of the rubber-tyred gantry crane, reduce the risk of accidents, reduce the labor intensity of the driver, reduce losses, reduce pollution, and improve efficiency. It adopts a method combining machine vision and a motion tracking mechanism. It uses the motion tracking mechanism to keep the recognition target of the camera always within the field of view of the camera, and combines the advantages of image recognition and range measurement using a reference object. It does not require the lines on the ground that are vulnerable to pollution, but comprehensively uses the information of the marks on the reference board in the image. The information on which the system is based is the image information in the two-dimensional space, that is, a range measurement information and an attitude information are extracted from the entire image information. Therefore, it can overcome various interference signals and obtain stable and reliable lateral positioning results. At the same time, the present invention has strong adaptability and can adapt to working conditions such as uneven ground in the stacking yard area, different installation heights of the reference board, tire pressure changes of the rubber-tyred gantry crane, and transfer of the rubber-tyred gantry crane, ensuring that the system can operate normally. The patent system has a simple structure, is safe and reliable, economical and practical, environmentally friendly, and has a wide range of applications. It can provide positioning information for the automatic driving of the rubber-tyred gantry crane, thereby effectively reducing the labor intensity of the driver of the rubber-tyred gantry crane. Brief Description of the Drawings

[0034] Figure 1 is a schematic framework diagram of the lateral positioning system of the gantry crane of the rubber-tyred gantry crane of the present invention;

[0035] Figure 2 is a schematic layout diagram of the lateral positioning system of the gantry crane of the rubber-tyred gantry crane of the present invention;

[0036] Figure 3 is a schematic diagram of the reference board in the lateral positioning system of the gantry crane of the rubber-tyred gantry crane of the present invention;

[0037] Figure 4 It is a schematic diagram of the target tracking mechanism in the lateral positioning system of the trolley of the container rubber-tyred gantry crane of the present invention;

[0038] Figure 5 It is a schematic diagram of each coordinate system in the lateral positioning system of the trolley of the container rubber-tyred gantry crane of the present invention;

[0039] Figure 6 It is a schematic diagram of the target tracking process in the lateral positioning method of the trolley of the container rubber-tyred gantry crane of the present invention;

[0040] Figure 7 It is a schematic diagram of the lateral positioning process of the trolley of the container rubber-tyred gantry crane based on machine vision in the lateral positioning method of the trolley of the container rubber-tyred gantry crane of the present invention. Detailed implementation manners

[0041] In order to better understand the above technical solutions of the present invention, the technical solutions of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0042] Combined with Figure 1 and Figure 2 As shown, a lateral positioning system for the trolley of a container rubber-tyred gantry crane provided by the present invention includes:

[0043] A reference plate 1, which is arranged on one side of the straight driving road of the trolley 5 of the rubber-tyred gantry crane;

[0044] A target tracking mechanism 2, which is arranged on the trolley 5 of the rubber-tyred gantry crane and is on the same side and at the same height as the reference plate 1;

[0045] An industrial camera 3, which is arranged on the target tracking mechanism 2, and the lens of the industrial camera 3 faces the reference plate 1;

[0046] An industrial computer 4, as an information processing unit, is arranged in the electrical room of the trolley 5 of the rubber-tyred gantry crane and establishes communication with the target tracking mechanism 2 and the industrial camera 3 through a TCP / IP network.

[0047] The upper and lower ranges of the observation area of the industrial camera 3 should include the position corresponding to the reference plate 1. The industrial camera 3 transmits the collected image data to the industrial computer 4. The image processing program running in the industrial computer 4 obtains the lateral position and attitude information of the current trolley, as well as the height information of the industrial camera 3 relative to the reference plate 1 through the processing of the image data. The industrial computer 4 transmits the height information of the industrial camera 3 relative to the reference plate 1 to the target tracking mechanism 2. The target tracking mechanism 2 controls the up and down movement of the industrial camera 3, and then follows the target to keep the target always within the field of view of the industrial camera 3.

[0048] The industrial computer 4 must make a judgment based on the current lateral position and attitude information of the trolley that it must obtain, as well as the height information of the industrial camera 3 relative to the reference plate 1, to determine whether it is valid. If the invalid duration of the pose information exceeds a set safety threshold, the system must adopt corresponding strategies, such as giving an alarm.

[0049] Combined with Figure 3 As shown, on both sides of the length of the reference plate 1, there are linear markings, including the upper marking 11 and the lower marking 12 that are arranged in parallel.

[0050] The distance between the centerlines of the upper marking 11 and the lower marking 22 is a fixed value d.

[0051] The upper marking 11 and the lower marking 12 are different in color from other areas of the reference plate 1 and need to have a certain contrast so that the industrial camera 3 can more easily extract the upper marking 11 and the lower marking 12 from the image.

[0052] Combined with Figure 4 As shown, on the target tracking mechanism 2, there is a guide rail 21 perpendicular to the ground direction, and a slider 22 that can move up and down along the guide rail 21. The industrial camera 3 is fixedly installed on the slider 22 and can move up and down with the slider 22. The target tracking mechanism 2 can control the up and down movement of the industrial camera 3 by controlling the up and down movement of the slider 22, so as to ensure that the upper marking 11 and the lower marking 22 in the reference plate 1 are always within the field of view of the industrial camera 3.

[0053] The target tracking mechanism 2 adjusts the up and down movement direction and speed of the slider 22 according to the height information of the industrial camera 3 relative to the reference plate 1 transmitted by the industrial computer 4, and traditional classical control methods or advanced high-level control methods (such as adaptive control, intelligent control, model predictive control, etc.) can be used to complete the target tracking task safely, reliably, and with high speed and high precision.

[0054] There is at least one set of industrial cameras 3, and each set of industrial cameras 3 is also equipped with an image sensor and lighting equipment.

[0055] The expected trajectory of the trolley 5 of the rubber-tyred gantry crane always remains parallel to the reference plate, and satisfies that the industrial camera 3 can obtain clear images of the upper marking line 11 and the lower marking line 22.

[0056] Combined with Figure 5 As shown, three coordinate systems are defined in the yard area, and the coordinate system O w X w Y w Z w is the world coordinate system, and its O w X wThe axis lies in the plane where the reference plate 1 is located, is parallel to both the upper mark 11 and the lower mark 12 on the reference plate 1, and has an equal distance from the upper mark 11 and the lower mark 12, O w Z w The axis is perpendicular to the ground and points upward, O w Y w The axis is perpendicular to the reference plate 1, and the direction is determined by the right - hand rule. Coordinate system O c X c Y c Z c is the camera coordinate system, where O c X c The axis is the row direction of the imaging plane of the industrial camera 3, O c Z c The axis is the column direction of the imaging plane of the industrial camera 3, O c Y c The axis is the optical axis of the industrial camera 3, satisfying the right - hand rule. Coordinate system O r X r Y r Z r is the vehicle body coordinate system (container gantry crane trolley 5), where the point O r is the geometric center point of the upper frame of the vehicle body, O r X r The axis points to the longitudinal direction of the vehicle body, O r Y r The axis points to the side direction of the vehicle body, O r Z r The axis is perpendicular to the ground and points vertically upward.

[0057] The present invention also provides a method for lateral positioning of a container gantry crane trolley. The target tracking process and the lateral positioning process of the gantry crane trolley based on machine vision are executed by using the lateral positioning system of the container gantry crane trolley of the present invention to obtain the lateral positioning result of the gantry crane trolley.

[0058] Combined with Figure 6 as shown, the above - mentioned target tracking process specifically includes the following steps:

[0059] S1. Obtain the images of the upper mark 11 and the lower mark 12 on the reference plate 1 in the industrial camera 3;

[0060] S2. Combining the internal parameter information in the industrial camera 3, extract the pixel points of the upper mark 11 and the lower mark 12 in the image coordinates {(u up ,v up ) i}(i = 1,2,…) and {(u down ,v down ) i}(i = 1,2,…) from the images;

[0061] S3, combining the distance d between the upper mark 11 and the lower mark 12 and {(u up ,v up ) i}(i=1,2,…),{(u down ,v down ) i}(i=1,2,…), calculate the point O c In O w Z w The projection value on the axis, that is, the height value h relative to the reference plate 1 c→w ;

[0062] S4, the height value h c→w Transmitted to the target tracking mechanism 2;

[0063] S5, the target tracking mechanism 2 controls the slider 22 to move in the opposite direction h c→w , thus reaching point O c With point O w Maintaining the same height means completing the tracking task marked in the following reference plate 1.

[0064] Combination Figure 7 As shown, the lateral positioning problem of the tire crane trolley 5 is to obtain point O r With O w X w The distance between the axes is d r→w , and O r X r Axis and O w X w The angle between the axes θ r→w The above-mentioned machine vision-based lateral positioning process of the tire crane trolley specifically includes the following steps:

[0065] Step 1: Calibrate the external parameters of industrial camera 3 to obtain the camera coordinate system O c X c Y c Z c With the vehicle coordinate system O r X r Y r Z r The conversion relationship between c→r ;

[0066] Step 2, obtaining images of the upper mark 11 and the lower mark 12 on the reference plate 1 in the industrial camera 3;

[0067] Step 3: Combine the internal parameter information of the industrial camera 3 and extract the pixel points of the upper mark 11 and the lower mark 12 in the image coordinates from the image {(u up ,v up )i}(i = 1, 2, …) and {(u down , v down ) i}(i = 1, 2, …);

[0068] Step 4: Combine the distance d between the upper identifier 11 and the lower identifier 12 and {(u up , v up ) i}(i = 1, 2, …), {(u down , v down ) i}(i = 1, 2, …) to calculate the distance value d r between point O w and the O w X r→w axis, and the angle θ r between the O r X w axis and the O w X r→w axis;

[0069] Step 5: Use the transformation relationship T c between the camera coordinate system O c X c Y c Z r X r Y r Z r of the vehicle body to calculate the distance value d c→r between point O r and the O w X w axis, and the angle θ r→w between the O r X r axis and the O w X w axis; r→w ;

[0070] Step 6: Output the lateral position and attitude information of the gantry crane trolley 5.

[0071] Machine vision is a multidisciplinary field that integrates knowledge from multiple fields such as optical engineering, electronic signal processing, pattern recognition, artificial intelligence, mechanical engineering, and software engineering. A machine vision system generally consists of devices such as a light source, a lens, an imaging device, an image storage unit, a monitor, and a computer system. The light source provides sufficient illumination for the vision system; the lens images the target in the measured scene onto the imaging surface of the vision sensor; the image storage unit is responsible for converting the electrical signal into a digital image, that is, converting the brightness of all pixel points into gray-level data and storing one or more images; the computer system is responsible for processing, analyzing, judging, and recognizing the image, and finally giving the detection result.

[0072] Object tracking is an important branch in machine vision, mainly applied in fields such as intelligent monitoring, autonomous driving, and target behavior analysis. For example, in the field of autonomous driving, the object tracking system tracks the surrounding obstacles in the vehicle driving environment, including targets such as pedestrians and vehicles, and gives information such as their future positions and speeds in advance. The object tracking algorithm automatically extracts and analyzes the trajectory characteristics of the target, provides help for visual target detection, effectively filters out incorrect targets, and fills in the missing targets. Typical algorithms include state prediction algorithms such as the Mean shift algorithm, the Kalman filter algorithm, and the particle filter algorithm, online learning tracking algorithms such as TLD, and correlation filtering tracking algorithms such as KCF. The prior assumption condition of the object tracking algorithm is that the target is always within the field of view of the camera. To solve the problem that the target is always within the field of view of the camera, a set of motion tracking mechanisms is required, which follows the target through the movement of the camera to keep the target always within the field of view of the camera.

[0073] The container tire crane trolley lateral positioning system and method proposed in the present invention are based on machine vision and object tracking, and adopt a combination of machine vision and motion tracking mechanisms. It uses the motion tracking mechanism to keep the recognition target of the camera always within the field of view of the camera, and combines the advantages of image recognition and range measurement using a reference object. It does not require easily contaminated lines on the ground, but comprehensively uses the information of the markings on the reference board in the image. The information on which the system is based is the image information in two-dimensional space, that is, a range measurement information and an attitude information are extracted from the entire image information. Therefore, it can overcome various interference signals and obtain stable and reliable lateral positioning results.

[0074] Embodiment

[0075] During the lateral positioning process of the container terminal tire crane trolley in this embodiment, the following steps are included:

[0076] S1. Construction of the reference plate 1 and production of the markings. The reference plate 1 can be constructed through a fixed bracket and installed in the yard, fixed along one side where the RTG crane trolley 5 travels straight, serving as a reference for maintaining a specific distance during the travel of the RTG crane trolley 5. The upper marking 11 and the lower marking 12 on the reference plate 1 are patterns that can be fixed on the reference plate 1 by means such as pasting, spraying, or hot melting. As Figure 3 shown, facing the RTG crane trolley 5. The colors of the upper marking 11 and the lower marking 12 can be set according to the color of the reference plate 1. The setting principle is that they can form a distinct contrast with the background of the reference plate 1, which is beneficial for subsequent image recognition and feature extraction by the industrial camera 3;

[0077] S2. The industrial camera 3 uses an industrial color camera with a resolution of 1280×720, selects a lens with a focal length of 8 mm, and the adaptive light source provides uniform illumination. The industrial camera 3 is fixed on the slider 22 of the target tracking mechanism 2 through a rigid body firmware, and the internal parameters of the industrial camera 3 are known before installation;

[0078] S3. Installation of the target following mechanism 2. The target tracking mechanism 2 selects a lead screw system and is rigidly fixed on the RTG crane trolley 5. The guide rail 21 is vertically downward, ensuring that the slider 22 can move in a direction perpendicular to the ground. During installation and fixation, ensure that the field of view of the industrial camera 3 fixed on the slider 22 can cover the upper marking 11 and the lower marking 12 on the reference plate 1 through the movement of the slider 22 and can clearly form images;

[0079] S4. Build the vehicle-mounted computing unit. The industrial computer 4 selects a high-performance industrial computer and is installed in the electrical cabinet of the RTG crane trolley 5. The program development and operation environment is Ubuntu18.04, and a third-party image processing library can also be used therein. The industrial computer 4 is connected to the industrial camera 3 and the target tracking mechanism 2 through an Ethernet data cable;

[0080] S5. Calibration of the external parameters of the industrial camera 3. Use a calibration plate and a total station to calibrate the industrial camera 3 to obtain the conversion relationship T c X c Y c Z c between the coordinate system O r X r Y r Z r of the industrial camera 3 and the vehicle body coordinate system O c→r and store it in the industrial computer 4;

[0081] S6. Through the target tracking process and the lateral positioning process of the RTG crane trolley based on machine vision, output the lateral positioning results of the RTG crane trolley 5, including lateral position and attitude information.

[0082] Those of ordinary skill in the art should recognize that the above embodiments are only used to illustrate the present invention, rather than to limit the present invention. As long as within the scope of the essential spirit of the present invention, changes and modifications to the above-described embodiments will fall within the scope of the claims of the present invention.

Claims

1. A trolley of a container crane Lateral positioning system, characterized in that, Comprising: A reference plate, provided on one side of the straight driving path of the trolley of the rubber-tyred gantry crane, serving as a reference for maintaining a specific distance during the driving of the trolley of the rubber-tyred gantry crane; On each of the two side edges of the reference plate in the length direction, there are linear markings, including an upper marking and a lower marking arranged in parallel; the colors of the upper marking and the lower marking are different from the color of the reference plate; A target tracking mechanism, provided on the trolley of the rubber-tyred gantry crane and on the same side as the reference plate; on the target tracking mechanism, there is a guide rail perpendicular to the ground direction and a slider moving up and down along the guide rail; An industrial camera, provided on the slider of the target tracking mechanism, and the lens of the industrial camera faces the reference plate; An industrial computer, provided in the electrical room of the trolley of the rubber-tyred gantry crane, and establishing communication with the target tracking mechanism and the industrial camera through a TCP / IP network, The industrial computer obtains the lateral position and attitude information of the current trolley and the height information of the industrial camera relative to the reference plate for judgment to determine whether it is valid, The lateral positioning system of the container rubber-tyred gantry crane trolley executes a target tracking process and a lateral positioning process of the rubber-tyred gantry crane trolley based on machine vision to obtain the lateral positioning result of the rubber-tyred gantry crane trolley, The target tracking process specifically includes the following steps: S1. Obtain the images of the upper marking and the lower marking on the reference plate in the industrial camera; S2. Combine the internal parameter information in the industrial camera to extract the pixel points \((u up , v up ) i}\) and \((u down , v down ) i} of the upper identifier and the lower identifier in the image coordinates, where \(i = 1, 2, \cdots, L\); S3. Combine the distance d between the upper identifier and the lower identifier and {(u up , v up ) i}, {(u down , v down ) i}, and calculate the projection value of point O c on the O w Z w axis, that is, the height value h c→w relative to the reference plate, where i = 1, 2, L; S4. Transmit the height value h c→w to the target tracking mechanism; S5. The target tracking mechanism controls the slider to displace in the opposite direction by h c→w , so as to reach point O c and point O w are maintained at the same height. The lateral positioning process of the rubber-tyred gantry crane trolley based on machine vision specifically includes the following steps: Step 1: Calibrate the external parameters of the industrial camera to obtain the camera coordinate system O c X c Y c Z c With the vehicle coordinate system O r X r Y r Z r The conversion relationship between c→r ; Step 2. Obtain the images of the upper marking and the lower marking on the reference plate in the industrial camera; Step 3: Combine the internal parameter information in the industrial camera to extract the pixel points \((u up , v up ) i} and \((u down , v down ) i} of the upper identifier and the lower identifier in the image coordinates, where \(i = 1, 2, \cdots\); Step 4. Combine the distance d between the upper identifier and the lower identifier and {(u up , v up ) i}, {(u down , v down ) i} to calculate the distance value d r between point O w and the O w X r→w axis, and the angle θ r between the O r X w axis and the O w X r→w axis, where i = 1, 2, L; Step 5: Use the camera coordinate system O c X c Y c Z c and the vehicle body coordinate system O r X r Y r Z r to calculate the conversion relationship T c→r between them, and calculate the distance value d r between point O w X w axis, and the angle θ r→w between the O r X r axis and the O w X w axis r→w ; Step 6. Output the lateral position and attitude information of the rubber-tyred gantry crane trolley.

2. The lateral positioning system of the container rubber-tyred gantry crane trolley according to claim 1, wherein: The upper marking and the lower marking are patterns fixed on the reference plate by means of pasting, spraying or hot melting.

3. The gantry crane lateral positioning system for container tire cranes according to claim 1, wherein: The reference plate is provided on one side of the straight driving path of the trolley of the rubber-tyred gantry crane through a fixing bracket.

4. The container tire crane trolley lateral positioning system according to claim 1, characterized in that: The industrial camera is also equipped with an image sensor and a lighting device.

5. The container tire crane trolley lateral positioning system according to claim 4, characterized in that: The industrial camera uses an industrial color camera with a resolution of 1280×720, and the focal length of the lens is 8mm.

6. A method for lateral positioning of the trolley of a container tire crane, characterized in that: Adopt the lateral positioning system of the container rubber-tyred gantry crane trolley according to any one of claims 1-5 to execute a target tracking process and a lateral positioning process of the rubber-tyred gantry crane trolley based on machine vision to obtain the lateral positioning result of the rubber-tyred gantry crane trolley, The target tracking process specifically includes the following steps: S1. Obtain the images of the upper marking and the lower marking on the reference plate in the industrial camera; S2. Combine the internal parameter information in the industrial camera to extract the pixel points \((u up , v up ) i} and \((u down , v down ) i} of the upper identifier and the lower identifier in the image coordinates, where \(i = 1, 2, \cdots\); S3. Combine the distance d between the upper identifier and the lower identifier and {(u up , v up ) i}, {(u down , v down ) i}, and calculate the projection value of point O c on the O w Z w axis, that is, the height value h c→w relative to the reference plate, where i = 1, 2, L; S4. Transmit the height value h c→w to the target tracking mechanism; S5. The target tracking mechanism controls the slider to displace in the opposite direction by h c→w , so as to reach point O c and point O w are maintained at the same height. The lateral positioning process of the rubber-tyred gantry crane trolley based on machine vision specifically includes the following steps: Step 1: Calibrate the external parameters of the industrial camera to obtain the camera coordinate system O c X c Y c Z c With the vehicle coordinate system O r X r Y r Z r The conversion relationship between c→r ; Step 2. Obtain the images of the upper marking and the lower marking on the reference plate in the industrial camera; Step 3: Combine the internal parameter information in the industrial camera to extract the pixel points \((u up , v up ) i} and \((u down , v down ) i} of the upper identifier and the lower identifier in the image coordinates, where \(i = 1, 2, \cdots, L\); Step 4. Combine the distance d between the upper identifier and the lower identifier, and {(u up , v up ) i}, {(u down , v down ) i} to calculate the distance value d r between point O w and the O w X r→w axis, and the angle θ r between the O r X w axis and the O w X r→w axis, where i = 1, 2, L; Step 5: Use the conversion relationship T c X c Y c Z c between the camera coordinate system O r X r Y r Z r and the vehicle body coordinate system O c→r to calculate the distance value d r between point O w X w axis and O r→w and the angle θ r X r axis and O w X w axis; r→w ; Step 6. Output the lateral position and attitude information of the rubber-tyred gantry crane trolley.

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