Wharf lifting appliance positioning system and method based on infrared light source shooting and gyroscope

Abstract

The invention provides a wharf lifting appliance positioning system based on infrared light source shooting and a gyroscope, which comprises an infrared camera arranged on a trolley mechanism of a rail-mounted gantry crane; the three infrared light sources are transversely arranged on a lifting appliance of the rail-mounted gantry crane at intervals; the gyroscope is arranged on the rail-mounted gantry crane and is used for acquiring a pitch angle theta p and a deviation angle theta xy of the mounting position of the gyroscope; the positioning controller is used for recognizing the posture information, position and angle state of the lifting appliance in real time, so that the posture of the lifting appliance is positioned and regulated; and the PLC is electrically connected with the trolley action mechanism, the cart action mechanism, the lifting appliance action mechanism and the gyroscope of the rail-mounted gantry crane. The invention provides a wharf lifting appliance positioning method based on infrared light source shooting and a gyroscope, which is realized through the positioning system and comprises the steps S1 to S5. The posture detection precision and the regulation and control efficiency of the automatic wharf lifting appliance are improved.

Description

Technical Field

[0001] The invention relates to the technical field of optical detection and positioning control of a dock crane spreader, and in particular to a dock spreader positioning system and method based on infrared light source shooting and a gyroscope. Background Art

[0002] Traditional container terminal rail cranes have the disadvantages of high driver workload and high labor costs. In their operating procedures, their loading and unloading effects are affected by changes in vision and ambient light sources, and are prone to misoperation, which can cause damage to equipment and goods, injuries to personnel, and certain safety hazards. In the process of automated container terminals or automated transformation of traditional container terminal yards, it is required that rail cranes can automatically grasp and place containers in the yard and have high requirements for automatic loading and unloading of containers on horizontal transport machinery. It is also required that the rail crane control system can detect and calculate the position and posture of the spreader (front and rear tilt angle, left and right tilt angle, left and right rotation angle, 20 feet, 40 feet, etc.) in real time under different terminal ambient light conditions to provide support for the automatic loading and unloading of rail cranes. However, since the terminal currently mainly uses the automatic container placement system and method for the terminal spreader based on machine vision, its loading and unloading effect is affected by changes in the driver's vision and ambient light sources (strong sunlight, insufficient light at night, etc.), and thus cannot meet the use requirements of the automatic rail crane operation of the automated container terminal. Summary of the invention

[0003] In view of this, it is necessary to propose a dock spreader positioning system and method based on infrared light source shooting and gyroscope to address the above problems, so as to overcome some shortcomings in the above-mentioned background technology and solve the following technical problems: How to improve the posture detection accuracy and control efficiency of automated dock spreaders through infrared light source shooting and gyroscope positioning.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] The present invention proposes a dock spreader positioning system based on infrared light source shooting and gyroscope, which is applied to the lifting equipment of the automated dock, and the lifting equipment is a shore bridge crane, a rail-mounted container gantry crane or a tire-mounted container gantry crane. The positioning system includes:

[0006] An infrared camera is installed on the trolley mechanism of the rail crane to obtain the current image information of the crane under the irradiation of the infrared light source;

[0007] Three infrared light sources are arranged horizontally on the hanger of the track hanger at intervals to provide infrared light sources for the infrared camera; the first infrared light source is located between the second infrared light source and the third infrared light source, the second infrared light source and the third infrared light source are used to calculate the center light source positioning coordinates, and the first infrared light source is used to detect the coordinates and perform the calculation center point coordinate verification;

[0008] The gyroscope is installed on the track crane to obtain the pitch angle θ of the gyroscope installation location. p and the deviation angle θ xy ;

[0009] The positioning controller is connected to the infrared camera, PLC controller and gyroscope respectively; the positioning controller is used to obtain the position information of the sling through the current image information of the infrared camera and the pitch angle θ of the gyroscope installation position obtained by the gyroscope positioning detection. p and the deviation angle θ xy Comparative analysis is performed to identify the posture information, position, and angle state of the spreader in real time, thereby realizing the positioning and control of the spreader posture; the spreader position information includes the spreader deviation value X in the space rectangular coordinate system in the direction of the trolley travel 灯偏差 , the deviation value Y of the hoist in the direction of the trolley 灯偏差 、The angle deviation value of the hoist θ 灯 ;

[0010] The PLC controller is electrically connected to the trolley motion mechanism, the carriage motion mechanism, the hoisting device motion mechanism and the gyroscope of the rail crane respectively.

[0011] Furthermore, the positioning controller is provided with an edge computing method, through which edge computing results are obtained, and according to the edge computing results, a sobel function is used to obtain the image function value f(x, y) of the space rectangular coordinate system of the sling, the deviation value X in the walking direction of the trolley 灯偏差 , the deviation value Y of the hoist in the direction of the trolley 灯偏差 and the angle deviation value θ of the spreader 灯 ; The edge computing method is operated in the process of calculating the gray value, gradient and gradient angle of each pixel point of the current image information; the edge computing result includes the gray value I in the travel direction X of the trolley in the spatial rectangular coordinate system of the sling n , the gray value I of the vehicle's travel direction Y n , the gradient value G(x) of the trolley's travel direction in the space rectangular coordinate system of the spreader, the gradient value G(y) of the trolley's travel direction in the space rectangular coordinate system of the spreader, the angle θ of the gradient of the space rectangular coordinate system of the spreader; the deviation value X of the spreader in the trolley's travel direction 灯偏差The coordinates of the spreader are calculated in real time in the travel direction X of the trolley and the deviation value of the command coordinates of the travel direction of the lifting equipment trolley; the deviation value Y of the spreader in the travel direction of the trolley 灯偏差 The deviation between the coordinates of the hoisting device in the trolley direction Y and the command coordinates of the lifting equipment trolley travel direction is calculated in real time.

[0012] Furthermore, the angle deviation value of the spreader

[0013] Furthermore, the gyroscope is used to detect the first angular velocity signal a corresponding to the walking direction X of the vehicle. x , the second angular velocity a corresponding to the vehicle's travel direction Y y , the third angular velocity signal a corresponding to the lifting direction Z of the sling z and scanning period T, and sends the angular velocity signals and scanning period T corresponding to the trolley travel direction X, the truck travel direction Y and the hoisting direction Z of the spreader to the positioning controller;

[0014] The positioning controller calculates the pitch angle θ of the gyroscope installation position according to the above angular velocity signals and the scanning period T. p and the deviation angle θ xy .

[0015] Furthermore, the positioning controller sets the deviation value X of the spreader in the direction of the trolley travel. 灯偏差 , the deviation value Y of the hoist in the direction of the trolley 灯偏差 、The angle deviation value of the hoist θ 灯 and the deviation angle θ xy , and the maximum deviation θ 差1 , minimum deviation θ 差2 In comparison, the PLC controller controls the actions of the various actuators of the rail crane to achieve automatic hoist positioning and deviation correction functions;

[0016] Maximum deviation θ 差1 , minimum deviation θ 差2 They are the deviation angle θ xy The two extreme endpoints of the comparison range.

[0017] Furthermore, the deviation angle θ xy The middle value of the range is the standard deviation angle θ when the sling is stationary in the standard posture xy差 .

[0018] This embodiment proposes a dock spreader positioning method based on infrared light source photography and a gyroscope, which is implemented by a dock spreader positioning system based on infrared light source photography and a gyroscope as described in any of the above items. The positioning method includes the following steps performed in sequence:

[0019] Step S1, the infrared camera obtains the current spreader image information under the irradiation of the infrared light source in real time, and transmits the current spreader image information to the positioning controller;

[0020] And the gyroscope will include the pitch angle θ p and the deviation angle θ xy The real-time information is transmitted to the positioning algorithm controller, which will also include the pitch angle θ p The real-time information is transmitted to the PLC controller;

[0021] Step S2, the positioning controller obtains the gray value, gradient and gradient angle of each pixel of the corresponding spreader infrared light source image through an edge calculation method according to the current spreader image information obtained in step S1;

[0022] Step S3: The positioning controller obtains the image function value f(x, y) of the spatial rectangular coordinate system of the sling and the deviation value X in the walking direction of the trolley through a Sobel function according to the gradient and gradient angle obtained in step S2. 灯偏差 , the deviation value Y of the hoist in the direction of the trolley 灯偏差 and the angle deviation value θ of the spreader 灯 ;

[0023] Step S4: the positioning controller calculates the motion information of the trolley motion mechanism, the truck motion mechanism, and the spreader motion mechanism, and the pitch angle θ according to the feedback from the PLC controller. p 、Deviation angle θ xy , Deviation value X in the direction of the car's movement 灯偏差 , the deviation value Y of the hoist in the direction of the trolley 灯偏差 and the angle deviation value θ of the spreader 灯 Perform spreader posture recognition to obtain alarm instructions or deviation correction instructions;

[0024] Step S5, when the positioning controller receives an alarm instruction, it issues a fault instruction to the PLC controller, and the PLC controller controls the relevant mechanisms of the lifting equipment to stop working, and prompts the maintenance personnel to stop the equipment to adjust the wire rope or replace the wire rope;

[0025] When the positioning controller receives the correction instruction, the PLC controller controls the spreader to move until the deviation value X in the direction of the trolley travels. 灯偏差 , the deviation value Y of the hoist in the direction of the trolley 灯偏差 、The angle deviation value of the hoist θ xy When all are zero or fall into a zeroing range, the spreader correction is stopped.

[0026] Further, in step S4, when the PLC controller detects that the currently controlled lifting device is not moving in the trolley travel direction X or the truck travel direction Y, and when the comparison formula θ is satisfied, p >θ p差 and θxy >θ xy差 When one of the following occurs, the positioning controller issues an alarm command; p差 To set the standard pitch angle threshold; θ xy差 It is the standard deviation angle of the sling when it is stationary in the standard posture.

[0027] Furthermore, in step S2, w white pixel numbers and pixel position information are obtained from the current spreader image information, that is, the image is divided into n blocks of unit pixels of the same area, and w white pixel numbers are obtained for each image area; the pixel position information includes the number and position of pixels.

[0028] Furthermore, in step S2, the gradient calculation process for each pixel point of the corresponding sling infrared light source image includes the following steps:

[0029] Step S11, the grayscale value of each pixel point of the sling infrared light source image can be decomposed into grayscale values ​​of different positions in the trolley walking direction X, the truck walking direction Y, and the sling lifting direction Z;

[0030] Step S12, using the Sobel operator to calculate the convolution of the gradient, and obtain the grayscale change of the pixel in the direction X in which the car travels;

[0031] Step S13, multiplying a matrix E with corresponding elements of a matrix composed of elements of a specified pixel in the image and its N neighborhoods, thereby obtaining the difference of the pixel in the direction X in which the vehicle is traveling. The differences of all pixels in the direction X in which the vehicle is traveling constitute a matrix Gx;

[0032] Step S14, refer to step S13 to calculate the difference Gy in the travel direction Y of the vehicle, so as to obtain the gradient G.

[0033] The beneficial effects of the present invention are:

[0034] The present invention will enable the crane to calculate and obtain the position, posture and angle of the spreader in real time under various dock environmental light sources and working conditions of the operating spreader shaking. Through the positioning of the spreader infrared light source and the gyroscope, the spreader posture information, position and angle state can be calculated and identified in real time, ensuring that the lifting equipment control system can identify the spreader posture and position, and more quickly, accurately and effectively grasp and release containers, realize the automatic grasping and release of yard containers by the rail crane, and the automatic loading and unloading of containers on horizontal transport machinery, and ensure the efficiency and safety of the automatic operation of the rail crane; the present invention improves the positioning accuracy of the spreader, and realizes the precise regulation of the spreader by the intervention of the gyroscope under a small range of target difference; the present invention improves the stability of the positioning system, and through the gyroscope and infrared light source, in the case of abnormal spreader posture, wire rope elongation damage causing spreader posture changes, and abnormal infrared light source shooting positioning, timely correction and stop positioning; the present invention reduces the susceptibility of the loading and unloading infrared light source to the influence of environmental light sources, and can correct the deviation through the intervention of the gyroscope, thereby improving the stability of the infrared light source shooting in strong light and darkness at noon;

[0035] The present invention also has the following advantages of being suitable for automated container terminal operations:

[0036] (1) Realize accurate and efficient operation of the automated auxiliary spreader box retraction and placement;

[0037] (2) It can receive the real-time detection and upload of spreader image information under different terminal ambient light conditions, and determine the current posture and position information of the spreader;

[0038] (3) Through the integration of gyroscope positioning and infrared light source shooting positioning, the current position and angle status of the spreader are monitored to achieve automatic and precise control;

[0039] (4) By cooperating with the control system of the lifting equipment, the precise placement of the lifting equipment during the automated operation of the rail crane is ensured, and the automatic grasping and release of containers in the yard and the automatic loading and unloading of containers on horizontal transport machinery are realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of the structural installation of the dock spreader positioning system based on infrared light source photography and gyroscope of the present invention;

[0041] Figure 2 It is a working flow chart of the dock spreader positioning method based on infrared light source shooting and gyroscope of the present invention;

[0042] Figure 3 A schematic diagram of the convolution process in Embodiment 3 of the present invention;

[0043] Figure 4 This is a working principle diagram of the gyroscope in Embodiment 3 of the present invention;

[0044] Description of reference numerals:

[0045] Lifting device—1, infrared light source—2, infrared camera—3, trolley mechanism—4, gyroscope—5, mounting frame—6. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be further clearly and completely described in combination with the embodiments of the present invention. It should be noted that the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0047] It should be understood that the directions or positional relationships indicated by terms such as "upper", "lower", "front", "back", "left", and "right" are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on the present invention.

[0048] The terms "first", "second", "third", "fourth", etc. 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 definition of "first", "second", "third", "fourth" features may explicitly or implicitly include one or more of the features.

[0049] Example 1

[0050] like Figure 1 As shown (where Figure 1 Mark 1 is the hanger, mark 2 is the infrared light source, mark 3 is the infrared camera, mark 4 is the trolley mechanism, mark 5 is the gyroscope, and mark 6 is the mounting bracket):

[0051] This embodiment proposes a dock spreader positioning system based on infrared light source photography and a gyroscope, which is applied to the lifting equipment of an automated dock, and the lifting equipment is a shore bridge crane, a rail-mounted container gantry crane or a tire-mounted container gantry crane, and is characterized in that the positioning system includes:

[0052] An infrared camera is installed on the trolley mechanism of the rail crane to obtain the current image information of the crane under the irradiation of the infrared light source;

[0053] Three infrared light sources are arranged horizontally on the hanger of the track hanger at intervals to provide infrared light sources for the infrared camera; the first infrared light source is located between the second infrared light source and the third infrared light source, the second infrared light source and the third infrared light source are used to calculate the center light source positioning coordinates, and the first infrared light source is used to detect the coordinates and perform the calculation center point coordinate verification;

[0054] The gyroscope is installed on the track crane to obtain the pitch angle θ of the gyroscope installation location. p and the deviation angle θ xy ;

[0055] The positioning controller is connected to the infrared camera, PLC controller and gyroscope respectively; the positioning controller is used to obtain the position information of the sling through the current image information of the infrared camera and the pitch angle θ of the gyroscope installation position obtained by the gyroscope positioning detection. p and the deviation angle θ xy Comparative analysis is performed to identify the posture information, position, and angle state of the spreader in real time, thereby realizing the positioning and control of the spreader posture; the spreader position information includes the spreader deviation value X in the space rectangular coordinate system in the direction of the trolley travel 灯偏差 , the deviation value Y of the hoist in the direction of the trolley 灯偏差 、The angle deviation value of the hoist θ 灯 ;

[0056] The PLC controller is electrically connected to the trolley motion mechanism, the carriage motion mechanism, the hoisting device motion mechanism and the gyroscope of the rail crane respectively.

[0057] Specifically, the three infrared light sources are in a triangular shape when observed from the front direction of the sling, that is, the first infrared light source is higher than the second infrared light source and the third infrared light source; the wharf coastline is in the same horizontal direction as the spatial coordinate system.

[0058] Preferably, the gyroscope is a device for detecting angular motion of a high-speed rotating body using a kinetic energy sensitive housing relative to an inertial space around one or two axes orthogonal to the axis of rotation; the gyroscope is disposed on an upper frame of a corresponding hanger of the rail crane; and the gyroscope is connected to a positioning controller for CAN communication.

[0059] Optimally, the positioning controller is provided with an edge computing method, through which edge computing results are obtained, and according to the edge computing results, a sobel function is used to obtain the image function value f(x, y) of the spatial rectangular coordinate system of the sling, the deviation value X in the walking direction of the trolley 灯偏差 , the deviation value Y of the hoist in the direction of the trolley 灯偏差 and the angle deviation value θ of the spreader 灯; The edge computing method is operated in the process of calculating the gray value, gradient and gradient angle of each pixel point of the current image information; the edge computing result includes the gray value I in the travel direction X of the trolley in the spatial rectangular coordinate system of the sling n , the gray value I of the vehicle's travel direction Y n , the gradient value G(x) of the trolley's travel direction in the space rectangular coordinate system of the spreader, the gradient value G(y) of the trolley's travel direction in the space rectangular coordinate system of the spreader, the angle θ of the gradient of the space rectangular coordinate system of the spreader; the deviation value X of the spreader in the trolley's travel direction 灯偏差 The coordinates of the spreader are calculated in real time in the travel direction X of the trolley and the deviation value of the command coordinates of the travel direction of the lifting equipment trolley; the deviation value Y of the spreader in the travel direction of the trolley 灯偏差 The deviation between the coordinates of the hoisting device in the trolley direction Y and the command coordinates of the lifting equipment trolley travel direction is calculated in real time.

[0060] Specifically, through edge computing, an accurate image of the infrared light source is generated, stray light is filtered out, and positioning accuracy is improved.

[0061] Optimized, spreader angle deviation value

[0062] The deviation value X of the sling in the direction of the trolley in formula (1) 灯偏差 The coordinates of the spreader are calculated in real time in the travel direction X of the trolley and the deviation value of the command coordinates of the travel direction of the lifting equipment trolley; the deviation value Y of the spreader in the travel direction of the trolley 灯偏差 The deviation between the coordinates of the hoisting device in the trolley direction Y and the command coordinates of the lifting equipment trolley travel direction is calculated in real time.

[0063] Optimally, the gyroscope is used to detect the first angular velocity signal a corresponding to the walking direction X of the vehicle. x , the second angular velocity a corresponding to the vehicle's travel direction Y y , the third angular velocity signal a corresponding to the lifting direction Z of the sling z and scanning period T, and sends the angular velocity signals and scanning period T corresponding to the trolley travel direction X, the truck travel direction Y and the hoisting direction Z of the spreader to the positioning controller;

[0064] The positioning controller calculates the pitch angle θ of the gyroscope installation position according to the above angular velocity signals and the scanning period T. p and the deviation angle θ xy .

[0065] Optimally, the positioning controller sets the deviation value X of the spreader in the direction of the trolley travel. 灯偏差 , the deviation value Y of the hoist in the direction of the trolley 灯偏差 、The angle deviation value of the hoist θ 灯and the deviation angle θ xy , and the maximum deviation θ 差1 , minimum deviation θ 差2 For comparison, the PLC controller controls the actions of the various actuators of the rail crane to achieve automatic positioning and deviation correction of the spreader (i.e., through real-time X deviation, Y deviation, and angle deviation, the PLC automatically controls the spreader action to move toward the trolley, truck, and tilt angle until the deviation value returns to zero);

[0066] Maximum deviation θ 差1 , minimum deviation θ 差2 They are the deviation angle θ xy The two extreme endpoints of the comparison range.

[0067] Specifically, through the deviation maximum value θ 差1 , minimum deviation θ 差2 Mathematical interval judgment, if it is greater than or less than the interval, the relevant function will not be executed.

[0068] Optimally, the deviation angle θ xy The middle value of the range is the standard deviation angle θ when the sling is stationary in the standard posture xy差 .

[0069] Example 2

[0070] like Figure 2 As shown:

[0071] This embodiment proposes a dock spreader positioning method based on infrared light source photography and a gyroscope, which is implemented by a dock spreader positioning system based on infrared light source photography and a gyroscope as described in any technical solution in Embodiment 1. The positioning method includes the following steps performed in sequence:

[0072] Step S1, the infrared camera obtains the current spreader image information under the irradiation of the infrared light source in real time, and transmits the current spreader image information to the positioning controller;

[0073] And the gyroscope will include the pitch angle θ p and the deviation angle θ xy The real-time information is transmitted to the positioning algorithm controller, which will also include the pitch angle θ p The real-time information is transmitted to the PLC controller;

[0074] Step S2, the positioning controller obtains the gray value, gradient and gradient angle of each pixel of the corresponding spreader infrared light source image through an edge calculation method according to the current spreader image information obtained in step S1;

[0075] Step S3: The positioning controller obtains the image function value f(x, y) of the spatial rectangular coordinate system of the sling and the deviation value X in the walking direction of the trolley through a Sobel function according to the gradient and gradient angle obtained in step S2. 灯偏差 , Deviation value Y of the hoist in the direction of the trolley 灯偏差 and the angle deviation value θ of the spreader 灯 ;

[0076] Step S4: the positioning controller calculates the motion information of the trolley motion mechanism, the trolley motion mechanism, the spreader motion mechanism, the pitch angle v, and the deviation angle θ according to the feedback from the PLC controller. xy , Deviation value X in the direction of the car's movement 灯偏差 , Deviation value Y of the hoist in the direction of the trolley 灯偏差 and the angle deviation value θ of the spreader 灯 Perform spreader posture recognition to obtain alarm instructions or deviation correction instructions;

[0077] Step S5, when the positioning controller receives an alarm instruction, it issues a fault instruction to the PLC controller, and the PLC controller controls the relevant mechanisms of the lifting equipment to stop working, and prompts the maintenance personnel to stop the equipment to adjust the wire rope or replace the wire rope;

[0078] When the positioning controller receives the correction instruction, the PLC controller controls the spreader to move until the deviation value X in the direction of the trolley travels. 灯偏差 , Deviation value Y of the hoist in the direction of the trolley 灯偏差 、The angle deviation value of the hoist θ xy When all are zero or fall into a zeroing range, the spreader correction is stopped.

[0079] Optimally, in step S4, when the PLC controller detects that the currently controlled spreader is not moving in the trolley travel direction X or the truck travel direction Y, and when the comparison formula θ is satisfied p >θ p差 and θ xy >θ xy差 When one of the following occurs, the positioning controller issues an alarm command; p差 To set the standard pitch angle threshold; θ xy差 It is the standard deviation angle of the sling when it is stationary in the standard posture.

[0080] Optimally, in step S2, w white pixel numbers and pixel position information are obtained from the current spreader image information, that is, the image is divided into n blocks of unit pixels of the same area, and w white pixel numbers are obtained for each image area; the pixel position information includes the number and position of pixels.

[0081] Optimally, in step S2, the gradient calculation process for each pixel of the corresponding sling infrared light source image includes the following steps:

[0082] Step S11, the grayscale value of each pixel point of the sling infrared light source image can be decomposed into grayscale values ​​of different positions in the trolley walking direction X, the truck walking direction Y, and the sling lifting direction Z;

[0083] Step S12, using the Sobel operator to calculate the convolution of the gradient, and obtain the grayscale change of the pixel in the direction X in which the car travels;

[0084] Step S13, multiplying a matrix E with corresponding elements of a matrix consisting of elements of a specified pixel in the image and N (N is preferably 8) neighborhoods of the specified pixel, thereby obtaining the difference of the pixel in the direction X in which the vehicle travels. The differences of all pixels in the direction X in which the vehicle travels constitute a matrix Gx;

[0085] Step S14, refer to step S13 to calculate the difference Gy in the travel direction Y of the vehicle, so as to obtain the gradient G.

[0086] Specifically, the gradient G = (G(x) 2 +G(y) 2 ) 1 / 2 .

[0087] Specifically, when the PLC controller controls the crane to grab or unload boxes, the infrared light source data is used to obtain data such as the spreader deviation angle in real time, which is compared with the deviation threshold and an alarm is triggered if it exceeds the threshold. The judgment process is that when the machine is stationary, the pitch angle, deviation angle, etc. are detected to determine whether the current spreader is in an abnormal posture. If there is an abnormality, the operation will be automatically stopped, and the maintenance personnel will be prompted to stop the machine to adjust or replace the wire rope.

[0088] The positioning system and positioning method of the present embodiment can integrate visual positioning and gyroscope positioning. The crane can obtain the position and angle posture of the spreader in real time, and identify the spreader's posture information, position, and status through the spreader's infrared light source and infrared camera arrangement and structure, and the gyroscope outputs angle information in various directions. The positioning system and positioning method ensure that the port lifting equipment control system can identify the spreader's posture and position, and can grab and release containers more quickly, accurately, and effectively, solving the problem of detecting the spreader's posture under different fields of view, ambient light sources, and changes in spreader working conditions.

[0089] Example 3

[0090] Embodiment 3 is a further optimization of Embodiment 1;

[0091] The infrared camera obtains the infrared structure light source image of the current spreader in real time, and obtains information such as the number of white pixels obtained by the infrared camera under the irradiation of the three infrared light sources of the current spreader. The edge computing algorithm is used, which includes the calculation process of grayscale value, gradient, and gradient angle, as follows:

[0092] (1) Grayscale value calculation: The image is divided into n blocks of unit pixels of the same area. The number of white pixels obtained in each image area is w. The grayscale value in the unit image is defined as:

[0093] I n =w n -(w1+w2+……+w n ) / n

[0094] (2) Gradient calculation: mainly to obtain the edge and direction, the grayscale values ​​of the three infrared light source images of the sling can be decomposed into different grayscale values ​​in the x (trolley direction), y (truck direction), and z (lifting direction):

[0095] I = f(x, y)

[0096] Where (x, y) is the coordinate, representing the horizontal axis x and the vertical axis y of the image, the function I represents the gray value of the pixel, and the gradient G(x) represents the maximum rate of change of the function f(x, y) at the point (x, y). The calculation expression is:

[0097]

[0098] For images, gradients can be calculated. Since digital images are composed of discrete grayscale values ​​of pixels, the differential operation becomes a difference. We can use the difference between two adjacent pixels to represent the change in the grayscale of the pixel in a certain direction. Use the Sobel operator to calculate the convolution of the gradient:

[0099] G(x)=conv2(img,A,'same')

[0100] G(y)=conv2(img,A,'same')

[0101] like Figure 3 As shown, Figure 3 It reflects a convolution process. The orange matrix E is the sobel operator, which can get the grayscale change of the pixel in the x direction. If we multiply the matrix E with the corresponding elements of the matrix composed of the elements of a pixel and its 8 neighbors in the image, we can get the difference of the pixel in the x direction. The differences of all pixels in the x direction constitute the matrix Gx. Similarly, we can also calculate the difference Gy in the y direction, so the size of the gradient G is:

[0102] G=(G(x) 2 +G(y) 2 ) 1 / 2

[0103] In addition, to generate the direction, we need to know the angle θ of the gradient,

[0104]

[0105] By calculating G and θ corresponding to (x, y) in the x, y coordinate system, we can generate three lamp image function values ​​f(x, y) based on the edge calculation algorithm in the x, y coordinate system, and obtain three values ​​of the calculated image: D lamp radius, and three lamp center coordinates (X1, Y1), (X2, Y2), (X3, Y3);

[0106] The calculation formula for the spreader height Z (lifting direction) is:

[0107] Through system calibration, when the up, down, left, and right micro-motor of the spreader does not move and the spreader is located at the center of the infrared camera, the calculation formula of the D light radius and spreader height Z of 3 meters, 9 meters, and 12 meters is:

[0108] Z 灯 =k D (D 实时 -D 3m )+3

[0109]

[0110] From the structure diagram, the direction of the trolley is the X direction, and the direction of the truck is the Y direction. At this time, assuming that the current height is Z, the calculation formula for the deviation of the spreader in the x and y directions is:

[0111]

[0112] When 3 meters, 9 meters, and 12 meters are substituted, the coordinates of the three lamp centers (X1, Y1), (X2, Y2), and (X3, Y3) are used to calculate the X-direction spreader deviation value. Similarly, the Y-direction deviation value can be calculated as follows:

[0113]

[0114] The above can be used to obtain the offset in the X and Y directions. In addition, the offset angle θ 灯 for:

[0115]

[0116] The gyroscope is arranged on the upper frame of the sling (such as Figure 1 As shown), the gyroscope is a device for detecting the angular motion of a high-speed rotating body relative to the inertial space around one or two axes orthogonal to the rotation axis using the momentum of the high-speed rotating body to sense the shell; the gyroscope is connected to the positioning algorithm controller using CAN signals, and outputs angular velocity signals and scanning periods T in the X (trolley direction), Y (truck direction), and Z (lifting direction) directions respectively.

[0117] like Figure 4 As shown, the angular velocity signals of X (trolley direction), Y (trolley direction), and Z (lifting direction) and the scanning period T and a of the gyroscope are output when the hoist is horizontal and the trolley, truck, and lifting directions are without deviation. x 、a y 、a z . To solve the angles of each axis:

[0118] Here, the angle between the X-axis (trolley direction) and the Z-axis (lifting) horizontal plane is defined as the pitch angle θ p , the angle between the X-axis (trolley direction) and the Y-axis (lifting) is the deviation angle θ xy Here, we first calculate the quaternion from the angular velocity, and then calculate the Euler angle from the quaternion. The first-order Runge-Kutta method is used to calculate the quaternion, and the derived formula is as follows:

[0119]

[0120] in:

[0121]

[0122] Substitute the initial values, q0 = 1, q1 = 0, q2 = 0, q3 = 0. And the scanning period T, a x 、a y 、a z , the derivation process is omitted, and the pitch angle θ is obtained p and the deviation angle θ xy :

[0123] θ p =arcsin(2(q0q2-q1q3))

[0124]

[0125] The pitch angle θ p and the deviation angle θ xy They are transmitted to the positioning controller respectively, and the pitch angle θ p The data is transmitted to the PLC controller to control the posture control of the stand-alone crane in the X direction, Y direction, and forward and backward tilt deviation during the automated operation of the rail crane. xy Perform infrared light source fusion positioning calculation.

[0126] Furthermore, the infrared light source and gyroscope hanger positioning control and logic mode:

[0127] (1) Automatic monitoring and alarm function for the hanger posture positioning

[0128] When the PLC controller detects that the direction of the trolley and the crane is not currently controlled, the pitch angle θ calculated by the gyroscope of the current positioning algorithm controller is monitored. pand the deviation angle θ xy When the spreader is stationary, set the threshold value θ p差 and the static deviation angle threshold θ xy差 , when stationary θ p >θ p差 , or θ xy >θ xy差 At this time, the positioning controller warns the PLC controller of a fault, such as during operation, θ p >θ p差 , or θ xy >θ xy差 , PLC automatically stops the operation and prompts the maintenance personnel to stop the machine to adjust or replace the wire rope.

[0129] (2) Automatic spreader positioning and correction:

[0130] When the PLC controller controls the crane to grab or unload boxes, the infrared light source data is used to obtain the X (trolley direction), Y (truck direction), and Z (lifting direction) of the spreader. 灯偏差 , Y 灯偏差 , Z 灯 Coordinate data, as real-time spreader position value.

[0131] The lifting direction positioning function is:

[0132] PLC controller through Z 灯 As the current spreader height, combined with the height of the loading / unloading target position, the difference between the current spreader height and the target position is obtained to control the distance of the spreader's lifting up / down movement, thereby realizing the spreader positioning and automatic box placement function.

[0133] Small and large vehicle direction positioning function:

[0134] ① The positioning controller uses an infrared light source and a gyroscope to calculate X 灯偏差 , Y 灯偏差 ,θ 灯 ,θ xy value, according to the controller set two constant threshold values ​​θ respectively 差1 , minimum deviation θ 差2 , and θ 差1 >θ 差2 .

[0135] ②When θ 差1 >|θ 灯 -θ xy |>θ 差2 hour,

[0136] The hoist tilt motor controls the stroke and angle of the action in X 灯偏差 , Y 灯偏差 ,θ灯 Until the PLC controller moves to X 灯偏差 , Y 灯偏差 ,θ 灯 After all are zero, the spreader positioning control action ends.

[0137] ③When |θ 灯 -θ xy |>θ 差1 hour,

[0138] The hoisting device tilting motor does not control the stroke and angle of the action, and reports a positioning deviation limit fault. At this time, the system prompts you to check whether the infrared light source installation and positioning parameters are correct, and check the status of the hoisting device and wire rope.

[0139] ④When θ 差2 >|θ 灯 -θ xy |When

[0140] The hoist tilt motor controls the stroke and angle of the action in X 灯偏差 , Y 灯偏差 ,θ xy Until the PLC controller moves to X 灯偏差 , Y 灯偏差 ,θ xy After all are zero, the spreader positioning control action ends.

[0141] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A dock spreader positioning system based on infrared light source shooting and gyroscope, applied to the lifting equipment of the automated dock, the lifting equipment is a shore bridge crane, a rail-mounted container gantry crane or a tire-mounted container gantry crane, characterized in that: The positioning system includes: An infrared camera is installed on the trolley mechanism of the rail crane to obtain current image information of the crane under the irradiation of the infrared light source; Three infrared light sources are arranged horizontally on the hanger of the track hanger at intervals to provide infrared light sources for the infrared camera; the first infrared light source is located between the second infrared light source and the third infrared light source, the second infrared light source and the third infrared light source are used to calculate the center light source positioning coordinates, and the first infrared light source is used to detect the coordinates and perform the calculation center point coordinate verification; The gyroscope is installed on the track crane to obtain the pitch angle θ of the gyroscope installation location. p and the deviation angle θ xy ; The positioning controller is connected to the infrared camera, PLC controller and gyroscope respectively; the positioning controller is used to obtain the position information of the sling through the current image information of the infrared camera and the pitch angle θ of the gyroscope installation position obtained by the gyroscope positioning detection. p and the deviation angle θ xy Comparative analysis is performed to identify the posture information, position, and angle state of the spreader in real time, thereby realizing the positioning and control of the spreader posture; the spreader position information includes the spreader deviation value X in the space rectangular coordinate system in the direction of the trolley travel 灯偏差 , the deviation value Y of the hoist in the direction of the trolley 灯偏差 、The angle deviation value of the hoist θ 灯 ; The PLC controller is electrically connected to the trolley motion mechanism, the carriage motion mechanism, the hoisting device motion mechanism and the gyroscope of the rail crane respectively.

2. The dock spreader positioning system based on infrared light source shooting and gyroscope according to claim 1 is characterized in that: The positioning controller is provided with an edge computing method, through which edge computing results are obtained, and according to the edge computing results, a sobel function is used to obtain the image function value f(x, y) of the space rectangular coordinate system of the sling, the deviation value X in the walking direction of the trolley 灯偏差 , Deviation value Y of the hoist in the direction of the trolley 灯偏差 and the angle deviation value θ of the spreader 灯 ; The edge computing method is operated in the process of calculating the gray value, gradient and gradient angle of each pixel point of the current image information; the edge computing result includes the gray value T of the trolley walking direction X in the spatial rectangular coordinate system of the sling. n , gray value I of the vehicle's travel direction Y n , the gradient value G(x) of the trolley's travel direction in the space rectangular coordinate system of the spreader, the gradient value G(y) of the trolley's travel direction in the space rectangular coordinate system of the spreader, the angle θ of the gradient of the space rectangular coordinate system of the spreader; the deviation value X of the spreader in the trolley's travel direction 灯偏差 The coordinates of the spreader are calculated in real time in the travel direction X of the trolley and the deviation value of the command coordinates of the travel direction of the lifting equipment trolley; the deviation value Y of the spreader in the travel direction of the trolley 灯偏差 The deviation between the coordinates of the hoisting device in the trolley direction Y and the command coordinates of the lifting equipment trolley travel direction is calculated in real time.

3. The dock spreader positioning system based on infrared light source shooting and gyroscope according to claim 2 is characterized in that: Spreader angle deviation 4. The dock spreader positioning system based on infrared light source shooting and gyroscope according to claim 1 is characterized in that: The gyroscope is used to detect the first angular velocity signal a corresponding to the walking direction X of the vehicle. r , the second angular velocity a corresponding to the vehicle's travel direction Y y , the third angular velocity signal a corresponding to the lifting direction Z of the sling z and scanning period T, and sends the angular velocity signals and scanning period T corresponding to the trolley travel direction X, the truck travel direction Y and the hoisting direction Z of the spreader to the positioning controller; The positioning controller calculates the pitch angle θ of the gyroscope installation position according to the above angular velocity signals and the scanning period T. p and the deviation angle θ xy .

5. The dock spreader positioning system based on infrared light source shooting and gyroscope according to claim 1 is characterized in that: The positioning controller sets the deviation value X of the spreader in the direction of the trolley travel 灯偏差 , Deviation value Y of the hoist in the direction of the trolley 灯偏差 、The angle deviation value of the hoist θ 灯 and the deviation angle θ xy , and the maximum deviation θ 差1 , minimum deviation θ 差2 In comparison, the PLC controller controls the actions of the various actuators of the rail crane to achieve automatic hoist positioning and deviation correction functions; Maximum deviation θ 差1 , minimum deviation θ 差2 They are the deviation angle θ xy The two extreme endpoints of the comparison range.

6. The dock spreader positioning system based on infrared light source shooting and gyroscope according to claim 1 is characterized in that: Deviation angle θ xy The middle value of the range is the deviation angle θ when the sling is stationary in the standard posture xy差 .

7. A dock spreader positioning method based on infrared light source shooting and gyroscope, which is implemented by the dock spreader positioning system based on infrared light source shooting and gyroscope as claimed in any one of claims 1 to 6, characterized in that: The positioning method includes the following steps performed in sequence: Step S1, the infrared camera obtains the current spreader image information under the irradiation of the infrared light source in real time, and transmits the current spreader image information to the positioning controller; And the gyroscope will include the pitch angle θ p and the deviation angle θ xy The real-time information is transmitted to the positioning algorithm controller, which will also include the pitch angle θ p The real-time information is transmitted to the PLC controller; Step S2, the positioning controller obtains the gray value, gradient and gradient angle of each pixel of the corresponding spreader infrared light source image through an edge calculation method according to the current spreader image information obtained in step S1; Step S3: The positioning controller obtains the image function value f(x, y) of the spatial rectangular coordinate system of the sling and the deviation value X in the walking direction of the trolley through a Sobel function according to the gradient and gradient angle obtained in step S2. 灯偏差 , Deviation value Y of the hoist in the direction of the trolley 灯偏差 and the angle deviation value θ of the spreader 灯 ; Step S4: the positioning controller calculates the motion information of the trolley motion mechanism, the truck motion mechanism, and the spreader motion mechanism, and the pitch angle θ according to the feedback from the PLC controller. p 、Deviation angle θ xy , Deviation value X in the direction of the car's travel 灯偏差 , Deviation value Y of the hoist in the direction of the trolley 灯偏差 and the angle deviation value θ of the spreader 灯 Perform spreader posture recognition to obtain alarm instructions or deviation correction instructions; Step S5, when the positioning controller receives an alarm instruction, it issues a fault instruction to the PLC controller, and the PLC controller controls the relevant mechanisms of the lifting equipment to stop working, and prompts the maintenance personnel to stop the equipment to adjust the wire rope or replace the wire rope; When the positioning controller receives the correction instruction, the PLC controller controls the spreader to move until the deviation value X in the direction of the trolley travels. 灯偏差 , the deviation value Y of the hoist in the direction of the trolley 灯偏差 、Deviation angle θ xy When all are zero or fall into a zeroing range, the spreader correction is stopped.

8. The method for positioning dock spreaders based on infrared light source photography and gyroscope according to claim 7, characterized in that: In step S4, when the PLC controller detects that the lifting device is not currently controlled to move in the trolley travel direction X or the truck travel direction Y, and when the comparison formula θ is satisfied p >θ p差 and θ xy >θ xy差 When one of the following occurs, the positioning controller issues an alarm command; p差 To set the standard pitch angle threshold; θ xy差 It is the standard deviation angle of the sling when it is stationary in the standard posture.

9. The method for positioning dock spreaders based on infrared light source photography and gyroscope according to claim 7, characterized in that: In step S2, the number of white pixels and pixel position information w are obtained from the current spreader image information, that is, the image is divided into n blocks of unit pixels of the same area, and the number of white pixels w is obtained for each image area; The pixel position information includes the number and position of pixels.

10. The dock spreader positioning method based on infrared light source shooting and gyroscope according to claim 7, characterized in that: In step S2, the gradient calculation process for each pixel of the corresponding sling infrared light source image includes the following steps: Step S11, the grayscale value of each pixel point of the sling infrared light source image can be decomposed into grayscale values ​​of different positions in the trolley walking direction X, the truck walking direction Y, and the sling lifting direction Z; Step S12, using the Sobel operator to calculate the convolution of the gradient, and obtain the grayscale change of the pixel in the direction X in which the car travels; Step S13, multiplying a matrix E with corresponding elements of a matrix composed of elements of a specified pixel in the image and its N neighborhoods, thereby obtaining the difference of the pixel in the direction X in which the vehicle is traveling. The differences of all pixels in the direction X in which the vehicle is traveling constitute a matrix Gx; Step S14, refer to step S13 to calculate the difference Gy in the travel direction Y of the vehicle, so as to obtain the gradient G.

Images