Lifting appliance posture detection method

Abstract

The invention discloses a lifting appliance posture detection method, and belongs to the technical field of automation equipment. A trolley mechanism is arranged on a cross beam of the gantry crane, and the trolley mechanism is provided with a first radar group and a second radar group; the method comprises the following steps: acquiring first scanning data acquired by a first radar group on a top plane of a lifting appliance and second scanning data acquired by a second radar group on the top plane of the lifting appliance; based on a first vertex group of the first scanning data and a second vertex group of the second scanning data, plane information of a top plane of the lifting appliance and a target intersection point between a first calibration line and a second calibration line are determined, the first vertex group is determined based on the first calibration line, and the second vertex group is determined based on the second calibration line; determining center point coordinates of the top plane of the lifting appliance according to the plane information and the target intersection point; and determining first attitude information of the lifting appliance by taking the center point coordinate and the target intersection point as calibration. According to the method, the pose of the lifting appliance can be detected in real time in the working process of the gantry crane.

Description

Technical Field

[0001] The present application belongs to the technical field of automation equipment, and in particular, relates to a method for detecting the posture of a sling. Background Art

[0002] In order to meet the growing transportation demand and improve the terminal's throughput capacity and operating efficiency, automated container terminals came into being.

[0003] As one of the core technologies of automated container terminals, the fully automatic container grabbing and placing technology verifies the spreader's position, which directly affects the container's accurate grabbing accuracy and detects the spreader's position in real time.

[0004] At present, the detection of the spreader's posture relies on the complete data from the 3D scanner's rotation scanning process, which requires stopping during the lifting process to wait for data collection. It is impossible to detect the spreader's posture in real time during the operation of the gantry crane. Summary of the invention

[0005] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a method for detecting the posture of a spreader, which can detect the posture of the spreader in real time during the operation of a gantry crane.

[0006] In a first aspect, the present application provides a method for detecting a spreader posture, which is applied to a gantry crane, wherein a trolley mechanism is provided on a crossbeam of the gantry crane, a spreader is provided at the bottom of the trolley mechanism, the trolley mechanism is provided with a first radar group and a second radar group, and a first mark plate group and a second mark plate group are provided on the top plane of the spreader, the first mark plate group is used to determine a first calibration line corresponding to the first radar group, and the second mark plate group is used to determine a second calibration line corresponding to the second radar group;

[0007] The method includes:

[0008] Acquire first scanning data collected by the first radar group on the top plane of the spreader, and second scanning data collected by the second radar group on the top plane of the spreader;

[0009] Determining plane information of a top plane of the spreader and a target intersection point between the first calibration line and the second calibration line based on a first vertex group of the first scan data and a second vertex group of the second scan data, wherein the first vertex group is determined based on the first calibration line and the second vertex group is determined based on the second calibration line;

[0010] Determine the center point coordinates of the top plane of the spreader according to the plane information and the target intersection point;

[0011] The first posture information of the lifting device is determined by calibrating the center point coordinates and the target intersection point.

[0012] According to one embodiment of the present application, the target intersection point is obtained based on the following steps:

[0013] According to the first vector and the second vector of the top plane of the spreader and the directional relationship between the plane vectors of the plane information, vector expressions of the first vector and the second vector are obtained, wherein the first vector and the second vector are used to characterize the shape characteristics of the top plane of the spreader;

[0014] The target intersection point is determined based on the vector representation of the first vector and the second vector, and the first vertex group and the second vertex group.

[0015] According to an embodiment of the present application, when the top plane of the sling is a rectangle, the first vector is perpendicular to the second vector, and the first vector and the second vector are respectively perpendicular to the plane vector, and the vector expression of the first vector and the second vector is obtained according to the directional relationship between the first vector and the second vector of the top plane of the sling and the plane vector of the plane information, including:

[0016] In the case where the first vector v1 = (x1, y1, z1), the second vector v2 is defined as:

[0017] v2=(y1*C-z1*B,z1*A-x1*C,x1*B-y1*A)

[0018] That is:

[0019] v2=v1×(A,B,C)

[0020] Among them, the plane vector is (A, B, C), (A, B, C) is taken as the unit vector, and × is the vector cross product;

[0021] The projection scalar of the vectors of the second vertex group P2 and P3 on the first vector v1 is a, and the projection scalar of the vectors of the first vertex group P1 and P4 on the second vector v2 is b, and we can get:

[0022] A*x1+B*y1+C*z1=0

[0023] (P2-P3)·v1 / ||v1||=a

[0024] (P1-P4)·v2 / ||v2||=b

[0025] Wherein, · represents the dot product. When the plane vector is a unit vector, according to the property of the cross product, ||v1||=||v2|| is obtained;

[0026] Among them, ||v1|| represents the 2-norm of the first vector v1, which is expressed as follows:

[0027]

[0028] get:

[0029] F·v1=g·||v1||

[0030] Among them, F is a 3*3 constant matrix, g is a 3*1 constant matrix, and the unit vector of the first vector v1 is obtained as follows

[0031]

[0032] The unit vector according to the first vector A unit vector of the second vector is obtained to determine vector expressions of the first vector and the second vector.

[0033] According to one embodiment of the present application, the target intersection includes an intersection G and an intersection H, and determining the target intersection based on the vector expression of the first vector and the second vector, and the first vertex group and the second vertex group includes:

[0034] The intersection point G is:

[0035]

[0036] The intersection point H is:

[0037]

[0038] in, is the transpose of the first vector v1.

[0039] According to an embodiment of the present application, determining the center point coordinates of the top plane of the spreader according to the plane information and the target intersection point includes:

[0040] The coordinates of the four corner points of the top plane of the sling are:

[0041] C1=G+v1·a1+v2·b1

[0042] C2=C1-v2·B1

[0043] C3=C2-v1·A1

[0044] C4=C3+v2·B1

[0045] Wherein, a1 is the distance between the second calibration line and the top plane edge of the spreader, b1 is the distance between the first calibration line and the top plane edge of the spreader, and A1 and B1 are the side lengths of the top plane edge of the spreader respectively;

[0046] According to the coordinates of the four corner points of the top plane of the sling, the coordinates of the center point are obtained as follows:

[0047] O=C1-0.5*v2·B1-0.5·v1·A1

[0048] Among them, v1 is the first vector of the top plane of the sling, and v2 is the second vector of the top plane of the sling.

[0049] According to an embodiment of the present application, the determining the first posture information of the spreader by using the center point coordinates and the target intersection point as calibration includes:

[0050] Determine, according to the center point coordinates, the offset of the spreader in the direction of the trolley mechanism, the offset of the spreader in the direction of the trolley mechanism of the gantry crane, and the lifting height of the spreader;

[0051] Determining the posture rotation angle of the spreader based on the target intersection point and the known point;

[0052] The first posture information is determined according to the directional offset of the spreader on the trolley mechanism, the directional offset of the spreader on the trolley mechanism, the lifting height of the spreader, and the posture rotation angle of the spreader.

[0053] According to one embodiment of the present application, after determining the first posture information of the spreader, the method further includes:

[0054] Using the first posture information as a reference, calculating second posture information of the target container;

[0055] Based on the difference between the first posture information and the second posture information, a posture deviation between the spreader and the target container is obtained.

[0056] According to an embodiment of the present application, the step of calculating the second posture information of the target container based on the first posture information includes:

[0057] Acquire third scanning data of the target container scanned by the second radar group;

[0058] Determining top surface information of the target container according to the third scanning data;

[0059] The second posture information is determined based on the first posture information and the top surface information.

[0060] According to an embodiment of the present application, obtaining the posture deviation between the spreader and the target container based on the difference between the first posture information and the second posture information includes:

[0061] Δx=xx 、

[0062] Δy=xx 、

[0063] Δα=α-α 、

[0064] Among them, Δx, Δy, and Δα are used to characterize the deviation value of the spreader relative to the target container, which are respectively the direction offset of the trolley mechanism, the direction offset of the gantry crane's trolley mechanism, and the angular offset of the spreader's lifting direction. The first posture information includes the spreader's direction offset x of the trolley mechanism, the spreader's direction offset y of the trolley mechanism, and the yaw angle α of the spreader. The second posture information includes the offset x of the target container relative to the center position of the trolley mechanism. 、 ,y 、 , and the rotation angle α of the target container around the lifting direction of the spreader 、 .

[0065] According to one embodiment of the present application, after obtaining the posture deviation between the spreader and the target container, the method further includes:

[0066] Based on the posture deviation, the posture of the spreader is adjusted.

[0067] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application.

[0068] The present invention provides a kind of hanger posture detection, which has the following beneficial effects compared with the prior art:

[0069] (1) By installing the first radar group and the second radar group at the bottom of the trolley mechanism, the influence of severe vibration and impact on the accuracy and service life is avoided. By scanning the first mark plate group and the second mark plate group set on the spreader, the center point coordinates and the target intersection point that calibrate the top plane of the spreader can be calculated, and the first posture information of the spreader can be calculated quickly and in real time. The position and posture of the spreader can be detected in real time during the operation of the gantry crane, providing data reference for the real-time adjustment of the spreader;

[0070] (2) By scanning the linear mark plate on the spreader and the target container under the spreader, the position information of the linear mark plate on the spreader is extracted to calculate the real-time posture of the spreader to obtain the first posture information. At the same time, the characteristics of the target container under the spreader are extracted to calculate the second posture information of the target container. The posture deviation between the spreader and the target container is calculated, and the posture of the spreader is adjusted in real time. The gantry crane can realize the functions of automatic grabbing and releasing containers in the container area, automatic grabbing containers in the lane, and stacking container inspection. The automation rate is high, the automatic operation process is smooth and there is no waiting process, the human intervention rate is low, the equipment failure rate is low, and the spreader's fully automatic dynamic adjustment positioning action and the spreader lifting action can be linked and run simultaneously, which greatly improves the operation efficiency. It plays an important role in improving loading and unloading efficiency, reducing labor costs, and ensuring operation safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0072] Figure 1 It is one of the structural schematic diagrams of the gantry crane provided in the embodiment of the present application;

[0073] Figure 2 This is the second structural schematic diagram of the gantry crane provided in the embodiment of the present application;

[0074] Figure 3 is a schematic diagram of the installation position of the linear sign board provided in the embodiment of the present application;

[0075] Figure 4 It is a schematic diagram of the installation of the first radar group and the second radar group provided in the embodiment of the present application in the direction of the trolley mechanism;

[0076] Figure 5 It is one of the flow charts of the method for detecting the posture of the spreader provided in the embodiment of the present application;

[0077] Figure 6 is a schematic plan view of the top plane of the spreader provided in an embodiment of the present application;

[0078] Figure 7 is a schematic plan view of the top of a target container provided in an embodiment of the present application;

[0079] Figure 8 This is the second flow chart of the method for detecting the posture of the sling provided in the embodiment of the present application. DETAILED DESCRIPTION

[0080] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0081] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0082] The following, in conjunction with the accompanying drawings, describes in detail the method for detecting the posture of a sling, the electronic device, and the readable storage medium provided in the embodiments of the present application through specific embodiments and their application scenarios.

[0083] The method for detecting the posture of the sling may be applied to a terminal, and may be specifically executed by hardware or software in the terminal.

[0084] The terminal includes, but is not limited to, a portable communication device such as a mobile phone or tablet computer with a touch-sensitive surface (e.g., a touch screen display and / or a touch pad). It should also be understood that in some embodiments, the terminal may not be a portable communication device, but a desktop computer with a touch-sensitive surface (e.g., a touch screen display and / or a touch pad).

[0085] In the following various embodiments, a terminal including a display and a touch-sensitive surface is described. However, it should be understood that the terminal may include one or more other physical user interface devices such as a physical keyboard, a mouse and a joystick.

[0086] The sling posture detection method provided in the embodiment of the present application can be executed by an electronic device or a functional module or functional entity in the electronic device that can implement the sling posture detection method. The electronic devices mentioned in the embodiment of the present application include but are not limited to mobile phones, tablet computers, computers, cameras and wearable devices. The sling posture detection method provided in the embodiment of the present application is described below using the electronic device as an example of the execution subject.

[0087] The method for detecting the posture of the lifting device provided in the embodiment of the present application is applied to a gantry crane, such as Figure 1 and Figure 2As shown, a trolley mechanism is provided on the crossbeam of the gantry crane, a hoist is provided at the bottom of the trolley mechanism, the trolley mechanism is provided with a first radar group and a second radar group, and a first mark plate group and a second mark plate group are provided on the top plane of the hoist, the first mark plate group is used to determine a first calibration line corresponding to the first radar group, and the second mark plate group is used to determine a second calibration line corresponding to the second radar group.

[0088] It can be understood that the gantry crane includes a gantry, a trolley mechanism, a car mechanism and a hoist. The gantry is a door-shaped structure formed by columns and beams on both sides. The trolley mechanism is installed at the bottom of the columns of the gantry and can drive the gantry to move along the track. The trolley mechanism is installed on the beams of the gantry. The hoist is a component used to grab and hang containers and is installed at the bottom of the trolley mechanism. The trolley mechanism can drive the hoist to move along the extension direction of the beams of the gantry.

[0089] Among them, the sling can be composed of hooks, chains or slings.

[0090] It can be understood that the first radar group includes two 2D scanners, which are arranged on the top of the platform of the trolley mechanism. The platform moves along the crossbeam direction of the gantry crane with the trolley mechanism, and its scanning direction is parallel to the running direction of the trolley mechanism.

[0091] The second radar group includes two 3D scanners, whose scanning directions are parallel to the running direction of the trolley mechanism. The 3D scanner may include a 2D scanner and a servo motor. During the operation of the 3D scanner, the angle parameters output by the servo motor perform angle correction on the scanning data of the 2D scanner, thereby realizing the output of 3D laser point cloud data.

[0092] Among them, the 2D scanner can be a laser radar.

[0093] In actual implementation, the top plane of the gantry crane's hoist is installed with a first mark plate group and a second mark plate group. The first mark plate group and the second mark plate group each include two linear mark plates. The linear mark plates correspond to the 2D scanner or 3D scanner one by one, and each linear mark plate is scanned in real time by a corresponding 2D scanner or 3D scanner.

[0094] The top plane of the sling may be rectangular.

[0095] It should be noted that the installation heights of the four linear markers are kept consistent to ensure that the vertices scanned by the first radar group (2D scanner) and the second radar group (3D scanner) are located on the same plane.

[0096] like Figure 3As shown, the two linear marker plates corresponding to the first radar group (2D scanner) are installed on the diagonal sides of the sling, such as the upper left and lower right or the upper right and lower left. Similarly, the two linear marker plates corresponding to the second radar group (3D scanner) are also installed on the diagonal sides of the sling, such as the upper left and lower right or the upper right and lower left.

[0097] Four linear marking plates are installed on the upper frame of the gantry crane. The cross-section of the linear marking plate is a cross-sectional figure with vertices, for example, a triangle. The line connecting all the cross-sectional vertices of the linear marking plate is a spatial straight line, which is the vertex straight line. Each linear marking plate is scanned in real time by the corresponding scanner on the top of the trolley mechanism.

[0098] When installing the linear sign plates, the linear sign plates scanned by the first radar group (2D scanner) are installed with their vertex straight lines parallel to the long sides of the slings, and the linear sign plates of the second radar group (3D scanner) are installed with their vertex straight lines parallel to the short sides of the slings. The two linear sign plates of the first sign plate group corresponding to the first radar group (2D scanner) and the two linear sign plates of the second sign plate group corresponding to the second radar group (3D scanner) can be installed on the same side or on different sides, and the specific installation position can be adjusted according to the on-site sling rack installation layout.

[0099] like Figure 4 As shown, according to the position of the linear mark plate on the spreader, the corresponding positions of the first radar group (2D scanner) and the second radar group (3D scanner) are determined on the top platform of the trolley mechanism to ensure that during the entire lifting operation of the spreader, the first radar group (2D scanner) can scan the outline of the linear mark plate throughout the entire process, and the second radar group (3D scanner) can track and scan the outline of the linear mark plate throughout the entire process through the rotation of the servo motor, and the installation position of the first radar group (2D scanner) and the second radar group (3D scanner) in the direction of the trolley mechanism should be outside the projection surface of the spreader on the small platform, and it should also be ensured that the first radar group (2D scanner) and the second radar group (3D scanner) are not blocked by the outer contour of the spreader or the container carried by the spreader when scanning the top surface of the target container.

[0100] It should be noted that the scanning modes of the second radar group (3D scanner) are horizontal scanning and rotation scanning.

[0101] like Figure 1 As shown, push scanning means that the gantry crane trolley mechanism outputs position information in real time during the movement to correct the position of each frame of the line point cloud of the second radar group (3D scanner), and all the line point clouds at the starting point and end point of the push scanning are spliced ​​and output as push point clouds.

[0102] like Figure 2As shown, rotation scanning refers to the real-time output of a line point cloud after the servo output angle is corrected during the rotation of the servo motor.

[0103] The first radar group (2D scanner) and the second radar group (3D scanner) scan the linear mark plate on the spreader and the top surface contour of the target container, and calculate the posture deviation between the spreader and the target container in real time, so as to realize the function of the spreader to dynamically adjust the posture of the target container during the entire lifting process, and complete the automatic grabbing and releasing of containers in the container area and the automatic grabbing of containers in the lane.

[0104] like Figure 5 As shown, the method for detecting the posture of the spreader includes: steps 510 to 540.

[0105] Step 510: Acquire first scanning data collected by the first radar group on the top plane of the spreader, and second scanning data collected by the second radar group on the top plane of the spreader.

[0106] The first scanning data is point cloud data collected by two 2D scanners in a horizontal manner, and the second scanning data includes line point cloud data collected by two 3D scanners in a rotating manner.

[0107] In this step, the first radar group (2D scanner) scans the top plane of the sling along the running direction of the trolley mechanism to obtain the first scanning data, and the second radar group (3D scanner) performs horizontal scanning and rotation scanning along the running direction of the trolley mechanism to obtain the second scanning data.

[0108] like Figure 6 As shown, the embodiment of the present application is explained by taking the example of a linear sign plate on a sling installed at the upper left and lower right of the sling. The type of the linear sign plate on the sling is a triangular sign plate, and its cross-section is a triangle. The type of linear sign plate includes triangular sign plates and is not limited to triangular sign plates.

[0109] Step 520: Determine the plane information of the top plane of the sling and the target intersection point between the first calibration line and the second calibration line based on the first vertex group of the first scan data and the second vertex group of the second scan data, wherein the first vertex group is determined based on the first calibration line and the second vertex group is determined based on the second calibration line.

[0110] The first vertex groups P1 and P4 corresponding to the first mark plate group are determined in the first scanning data, and the second vertex groups P2 and P3 of the second mark plate group are determined in the second scanning data.

[0111] The first calibration line and the second calibration line are respectively determined according to the lines formed by the first radar group and the second radar group during the scanning process, and the target intersection points between the first calibration line and the second calibration line are G and H respectively.

[0112] Since the four points P1, P2, P3, and P4 are on the same plane, the plane equation of the plane can be obtained:

[0113] Ax+By+Cz+D=0

[0114] This plane equation is used as plane information of the top plane of the spreader.

[0115] Step 530: Determine the center point coordinates of the top plane of the hanger according to the plane information and the target intersection point.

[0116] It can be understood that the center point coordinate O is the centroid of the top plane of the sling.

[0117] In this step, based on the plane information Ax+By+Cz+D=0 of the target intersection points G, H and the top plane of the sling, the projection line segment of the line between the target intersection points G, H on the plane information Ax+By+Cz+D=0 can be obtained, and based on the projection line segment, the coordinates O of the center point of the sling can be calculated.

[0118] Step 540: Determine the first posture information of the lifting device by calibrating the center point coordinates and the target intersection point.

[0119] In this step, the top plane of the spreader is calibrated by the center point coordinate O and the target intersection points G and H to obtain information such as the position, tilt direction and tilt degree of the spreader in space, and this information is used as the first posture information.

[0120] According to the method for detecting the posture of the spreader provided in the embodiment of the present application, by installing the first radar group and the second radar group at the bottom of the trolley mechanism, the influence of severe vibration and impact on the accuracy and service life is avoided. By scanning the first mark plate group and the second mark plate group arranged on the spreader, the center point coordinates and the target intersection point that serve as calibration for the top plane of the spreader can be calculated, the first posture information of the spreader can be calculated quickly and in real time, the position and posture of the spreader can be detected in real time during the operation of the gantry crane, and data reference can be provided for real-time adjustment of the spreader.

[0121] In some embodiments, the target intersection point is obtained based on the following steps:

[0122] According to the first vector and the second vector of the top plane of the spreader and the directional relationship between the plane vectors of the plane information, vector expressions of the first vector and the second vector are obtained, wherein the first vector and the second vector are used to characterize the shape characteristics of the top plane of the spreader;

[0123] The target intersection point is determined based on the vector representation of the first vector and the second vector, and the first vertex group and the second vertex group.

[0124] Among them, the first vector v1 is parallel to the long side of the top plane of the spreader, and the second vector v2 is parallel to the short side of the top plane of the spreader. According to the plane information Ax+By+Cz+D=0 of the top plane of the spreader, the unit normal vector (A, B, C) can be obtained as a plane vector, satisfying A 2 +B 2 +C 2 =1.

[0125] like Figure 6 As shown, after obtaining the first vertex group P1, P4 and the second vertex group P2, P3, the target intersection point of the first calibration line where P1 is located and the second calibration line where P2 is located is G, and the target intersection point of the second calibration line where P3 is located and the second calibration line where P4 is located is H.

[0126] In this step, by determining the target intersection point of the first calibration line and the second calibration line, a basis is provided for faster and more accurate calculation of the position and posture of the spreader.

[0127] In some embodiments, when the top plane of the sling is a rectangle, the first vector is perpendicular to the second vector, and the first vector and the second vector are respectively perpendicular to the plane vector, and the vector expression of the first vector and the second vector is obtained according to the directional relationship between the first vector and the second vector of the top plane of the sling and the plane vector of the plane information, including:

[0128] In the case where the first vector v1 = (x1, y1, z1), the second vector v2 is defined as:

[0129] v2=(y1*C-z1*B,z1*A-x1*C,x1*B-y1*A)

[0130] That is:

[0131] v2=v1×(A,B,C)

[0132] Among them, the plane vector is (A, B, C), (A, B, C) is taken as the unit vector, and × is the vector cross product;

[0133] The projection scalar of the vectors of the second vertex group P2 and P3 on the first vector v1 is a, and the projection scalar of the vectors of the first vertex group P1 and P4 on the second vector v2 is b, and we can get:

[0134] A*x1+B*y1+C*z1=0

[0135] (P2-P3)·v1 / ||v1||=a

[0136] (P1-P4)·v2 / ||v2||=b

[0137] Among them, · represents the dot product, ||v1|| represents the 2-norm of the first vector v1, which is expressed as follows:

[0138]

[0139] In the case where the plane vector is a unit vector. According to the definition of a unit vector (a vector with a 2-norm of 1), ||(A,B,C)||=1. According to the property of the cross product ||s×t||=||s||·||t||·sinθ, where s and t are any two vectors and θ is the angle between s and t, we get ||v2||=||v1||·||(A,B,C)||=||v1||;

[0140] get:

[0141] F·v1=g·||v1||

[0142] Among them, F is a 3*3 constant matrix, g is a 3*1 constant matrix, and the unit vector of the first vector v1 is obtained as follows

[0143]

[0144] The unit vector according to the first vector A unit vector of the second vector is obtained to determine vector expressions of the first vector and the second vector.

[0145] Among them, the projection scalar is the component of a vector in the direction of another vector, and the vector expression is to represent its position in a certain coordinate system through the components of the vector.

[0146] In this step, through the above steps, the vector expression of the first vector and the second vector can be accurately and quickly obtained, providing a basis for the calculation of the position and posture of the sling.

[0147] In some embodiments, the target intersection includes an intersection G and an intersection H, and determining the target intersection based on the vector expression of the first vector and the second vector, and the first vertex group and the second vertex group includes:

[0148] The intersection point G is:

[0149]

[0150] The intersection point H is:

[0151]

[0152] in, is the transpose of the first vector v1.

[0153] In this embodiment, the position and posture of the spreader can be accurately and quickly calibrated by calculating the coordinates of the target intersection point.

[0154] In some embodiments, Figure 6 As shown, the determining the center point coordinates of the top plane of the spreader according to the plane information and the target intersection point includes:

[0155] The coordinates of the four corner points of the top plane of the sling are:

[0156] C1=G+v1·a1+v2·b1

[0157] C2=C1-v2·B1

[0158] C3=C2-v1·A1

[0159] C4=C3+v2·B1

[0160] Wherein, a1 is the distance between the second calibration line and the top plane edge of the spreader, b1 is the distance between the first calibration line and the top plane edge of the spreader, and A1 and B1 are the side lengths of the top plane edge of the spreader respectively;

[0161] According to the coordinates of the four corner points of the top plane of the sling, the coordinates of the center point are obtained as follows:

[0162] O=C1-0.5*v2·B1-0.5*v1·A1

[0163] Among them, x1 is the first vector of the top plane of the spreader, and v2 is the second vector of the top plane of the spreader.

[0164] In addition, the rotation angle of the spreader around the lifting direction can also be calculated through the coordinates of the four corner points of the top plane of the spreader.

[0165] In this embodiment, by calculating the coordinates of the center point of the top plane of the sling, the position and posture of the sling can be calibrated more accurately.

[0166] In some embodiments, the determining the first posture information of the spreader by using the center point coordinates and the target intersection point as calibration includes:

[0167] Determine, according to the center point coordinates, the offset of the spreader in the direction of the trolley mechanism, the offset of the spreader in the direction of the trolley mechanism of the gantry crane, and the lifting height of the spreader;

[0168] Determining the posture rotation angle of the spreader based on the target intersection point and the known point;

[0169] The first posture information is determined according to the directional offset of the spreader on the trolley mechanism, the directional offset of the spreader on the trolley mechanism, the lifting height of the spreader, and the posture rotation angle of the spreader.

[0170] Among them, the three components of the center point coordinate O are the offset x of the sling in the direction of the trolley mechanism, the offset y of the trolley mechanism, and the lifting height z of the sling.

[0171] It can be understood that the attitude rotation angle includes a pitch angle β, a roll angle γ and a yaw angle α, and correspondingly, the first attitude information is (x, y, z, γ, β, α).

[0172] The roll angle γ is calculated first, followed by the pitch angle β, and finally the yaw angle α.

[0173] Using the target intersection points G and H, and any known point K, G1, H1, and K1 represent the starting coordinates of points G, H, and K respectively. The starting coordinates are the coordinates when the spreader is on the ground and leveled. The height z values ​​of G1, H1, and K1 are all 0, and the pitch angle β, roll angle γ, and yaw angle α are all 0. The following relationship can be obtained:

[0174]

[0175] β=asin(-matrix(3,1))

[0176] γ=asin(matrxi(3,2) / cos(β))

[0177] α=asin(matrix(2,1) / cos(β))

[0178] Among them, matirx represents the rotation matrix, G 、 , H 、 , K 、 , O 、 are the transposes of G, H, K and O respectively, They are the transpose of G1, H1, and K1 respectively.

[0179] In some embodiments, after obtaining the posture, the method further includes:

[0180] Using the first posture information as a reference, calculating second posture information of the target container;

[0181] Based on the difference between the first posture information and the second posture information, a posture deviation between the spreader and the target container is obtained.

[0182] In the actual implementation, two 2D scanners and two 3D scanners are used to scan the four linear marker plates on the spreader, extract the geometric features of the linear marker plates, and calculate the real-time posture of the spreader relative to the center position of the trolley mechanism as the first posture information.

[0183] The top surface of the target container is scanned horizontally by two 3D scanners to obtain a 3D point cloud. The top surface features of the target container are extracted from the point cloud and the second posture information of the target container is calculated.

[0184] According to the first posture information of the spreader and the second posture information of the target container, the posture deviation of the spreader relative to the target container in the trolley direction, the truck direction, and the rotation angle direction around the lifting direction is obtained.

[0185] In addition, dynamic real-time adjustments can be made during the lifting process of the spreader so that the posture deviation continues to approach the set threshold, thus realizing the automatic adjustment function of the spreader during the entire lifting process, and completing the actions of the spreader automatically grabbing and releasing boxes in the box area and automatically grabbing boxes in the lane.

[0186] In some embodiments, the calculating the second posture information of the target container based on the first posture information includes:

[0187] Acquire third scanning data of the target container scanned by the second radar group;

[0188] Determining top surface information of the target container according to the third scanning data;

[0189] The second posture information is determined based on the first posture information and the top surface information.

[0190] It can be understood that the third scanning data includes a 3D flat point cloud of the target container.

[0191] like Figure 7 As shown, the top surface point cloud of the target container is extracted from the third scanning data of the 3D scanner's push scan, and the two long sides and two short sides of the top surface of the target container are fitted to obtain the four corner points Pt1, Pt2, Pt3, and Pt4 of the top surface of the target container as the top surface information of the target container.

[0192] According to the coordinates of the four corner points of the top surface information and the first posture information, the second posture information (x 、 ,y 、 ,z 、 ,α 、 ).

[0193] Among them, x、 ,y 、 ,z 、 are the offsets of the target container relative to the center position of the trolley mechanism, α 、 It is the rotation angle of the target container around the lifting direction of the spreader.

[0194] x 、 =(Pt1.x+Pt2.x+Pt3.x+Pt4.x) / 4

[0195] y 、 =(Pt1.y+Pt2.y+Pt3.y+Pt4.y) / 4

[0196] z 、 =(pt1.z+Pt2.z+Pt3.z+Pt4.z) / 4

[0197]

[0198] Among them, Pt1, Pt2, Pt3, and Pt4 are the four corner points of the top surface of the target container, x is the offset of the spreader in the direction of the trolley mechanism, y is the offset of the spreader in the direction of the trolley mechanism, and z is the lifting height of the spreader.

[0199] In some embodiments, obtaining the posture deviation between the spreader and the target container based on the difference between the first posture information and the second posture information includes:

[0200] Δx=xx 、

[0201] Δy=xx 、

[0202] Δα=α-α 、

[0203] Among them, Δx, Δy, and Δα are used to characterize the deviation value of the spreader relative to the target container, which are respectively the direction offset of the trolley mechanism, the direction offset of the gantry crane's trolley mechanism, and the angular offset of the spreader's lifting direction. The first posture information includes the spreader's direction offset x of the trolley mechanism, the spreader's direction offset y of the trolley mechanism, and the yaw angle α of the spreader. The second posture information includes the offset x of the target container relative to the center position of the trolley mechanism. 、 ,y 、 , and the rotation angle α of the target container around the lifting direction of the spreader 、 , the posture deviation is (Δx, Δy, Δα).

[0204] In some embodiments, after obtaining the posture deviation between the spreader and the target container, the method further includes:

[0205] Based on the posture deviation, the posture of the spreader is adjusted.

[0206] In actual implementation, the PLC can be used to drive the spreader to continuously make micro-adjustments so that the posture deviation is as close to 0 as possible, thereby achieving dynamic real-time adjustment of the spreader during the entire lifting process.

[0207] After the spreader completes placing the target container, a stacking check can also be performed to compare the posture deviation between the spreader's first posture information at this time and the second posture information of the target container. If the posture deviation is within the threshold range, the stacking check passes; if the posture deviation is not within the threshold range, the stacking check fails.

[0208] In this embodiment, by calculating the posture deviation of the spreader relative to the target container, the spreader can realize functions such as automatic and accurate container grabbing / automatic container placement / stacked container verification, thereby improving the automation level of the gantry crane and the efficiency of fully automatic operation.

[0209] In the related art, there are many methods for detecting the position and posture of the sling.

[0210] First, the detection of the spreader posture mainly involves installing sensors on the spreader to detect the difference between the spreader and the target container posture. The laser scanner on the spreader is used to scan the contour of the top of the target container, and the spreader's rotation angle difference in the trolley mechanism / trolley mechanism direction and the lifting direction is calculated by extracting the feature contour to achieve the function of the spreader automatically adjusting the posture of the target container. This method has two major disadvantages:

[0211] The attitude deviation value can only be output and adjusted after the hoisting device is lifted to a certain height from the top surface of the container, and dynamic adjustment cannot be achieved during the entire lifting process;

[0212] The operating environment of the gantry crane is harsh, accompanied by various severe vibrations and impacts, which greatly affects the service life of the high-precision laser scanner equipment installed on the crane.

[0213] The present application can be dynamically adjusted during the entire lifting process of the sling, and the first radar group and the second radar group are installed at the bottom of the trolley mechanism, avoiding the influence of severe vibration and impact on accuracy and service life.

[0214] Secondly, the sling posture is detected by scanning the four mark plates on the sling with the scanner on the top platform of the trolley mechanism. The sling posture is calculated only through two-dimensional plane projection. However, this method does not consider the influence of the components in various directions of the three-dimensional space. The calculation result cannot accurately represent the posture information of the current sling.

[0215] The calculation of the first posture information in the present application is performed in three-dimensional space, which can accurately characterize the current posture of the spreader.

[0216] Thirdly, the 3D scanner is used to rotate and scan the target container in the yard and the container carried by the spreader when the spreader is at two different heights to obtain the offset of the spreader in the direction of the large and small car mechanism, and the 2D scanner is used to scan the spreader mark plate and the characteristics of the target container in the yard to obtain the rotation offset of the spreader around the lifting direction, thereby realizing the method of automatic stacking of containers in the container area. This method has the following disadvantages:

[0217] Relying on the complete data of the 3D scanner during the rotation scanning process, it is necessary to stop during the lifting process and wait for data collection, which affects the working efficiency. In addition, the characteristics of the containers carried by the spreader need to be collected. For the working conditions of grabbing containers in the container area and the lane, the spreader does not have the characteristics of the containers carried by the spreader, and the automatic container grabbing function cannot be realized.

[0218] This application can detect the position and posture of the spreader in real time during the operation of the gantry crane, and provide data reference for the real-time adjustment of the spreader.

[0219] An embodiment is described below.

[0220] like Figure 8 As shown, after the gantry crane receives the operation instruction, the trolley mechanism automatically moves to the top of the target container. During the movement, the angle of the 3D scanner moves vertically downward to perform a horizontal push scan, so that the edge point fitting straight lines of the long side and the short side of the target container can be obtained, and the posture of the target container relative to the center of the trolley mechanism is calculated as the second posture information;

[0221] The trolley mechanism starts to lift the spreader after reaching the target row. At this time, the 2D scanner and the 3D scanner scan the linear sign plate on the spreader and the top surface of the target container. The servo motor in the 3D scanner tracks the linear sign plate on the spreader for scanning during the spreader lifting process. Both the 2D scanner and the 3D scanner can scan the corresponding linear sign plate during the entire lifting process of the spreader.

[0222] During the lifting process of the spreader, according to the geometric features of the point cloud of the four linear markers of the spreader, the real-time posture of the spreader is calculated according to the coordinates of the feature points to obtain the first posture information;

[0223] During the lifting process of the spreader, the posture deviation of the spreader relative to the top surface of the target container is calculated based on the first posture information of the spreader and the second posture information of the target container, mainly including the direction offset of the trolley mechanism, the direction offset of the carriage mechanism, and the angular offset of the rotation around the lifting direction of the spreader;

[0224] During the lifting process of the spreader, the posture deviation of the spreader relative to the top surface of the target container is adjusted in real time. If the posture deviation is less than the threshold, the spreader posture adjustment is terminated and the posture is kept lowered; if the posture deviation is greater than or equal to the threshold, the posture is dynamically adjusted during the lifting process of the spreader until the posture deviation is less than the threshold, and the adjustment is completed;

[0225] The whole dynamic adjustment process of the spreader is carried out synchronously with the lifting action of the spreader. A minimum adjustment height can be set. If the automatic adjustment cannot be completed before this height, the lifting action of the spreader will stop until the posture adjustment is completed. If the automatic adjustment is completed before this height, the lifting action of the spreader will not stop, and the process of automatic box grabbing in the box area / automatic box placement in the box area / automatic box grabbing in the lane can be realized;

[0226] After the spreader has completed placing the container, the stacking verification function is performed to compare the spreader's posture at this time with the target container posture deviation. If the posture deviation is within the threshold range, the stacking verification passes; if the posture deviation is not within the threshold range, the stacking verification fails.

[0227] In this embodiment, the functions of calculating the spreader posture based on laser radar scanning of the spreader linear mark plate and the top surface of the target container, and calculating the spreader posture deviation relative to the target container are realized. The automation rate is high, the automatic operation process is smooth and there is no waiting process, the human intervention rate is low, the equipment failure rate is low, and the spreader's fully automatic dynamic adjustment positioning action and the spreader lifting action can be linked and run simultaneously, which greatly improves the operating efficiency. It plays an important role in improving loading and unloading efficiency, reducing labor costs, and ensuring operation safety.

[0228] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0229] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a computer software product, which is stored in a storage medium (such as ROM / RAM, a disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the hanger posture detection method of each embodiment of the present application.

[0230] In the description of this application, "first feature" or "second feature" may include one or more of the features.

[0231] In the description of the present application, “plurality” means two or more.

[0232] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

[0233] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0234] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A method for detecting a hanger posture, characterized in that: Applied to a gantry crane, a trolley mechanism is provided on the crossbeam of the gantry crane, a hoist is provided at the bottom of the trolley mechanism, the trolley mechanism is provided with a first radar group and a second radar group, a first mark plate group and a second mark plate group are provided on the top plane of the hoist, the first mark plate group is used to determine a first calibration line corresponding to the first radar group, and the second mark plate group is used to determine a second calibration line corresponding to the second radar group; The method comprises: Acquire first scanning data collected by the first radar group on the top plane of the spreader, and second scanning data collected by the second radar group on the top plane of the spreader; Determining plane information of a top plane of the spreader and a target intersection point between the first calibration line and the second calibration line based on a first vertex group of the first scan data and a second vertex group of the second scan data, wherein the first vertex group is determined based on the first calibration line and the second vertex group is determined based on the second calibration line; Determining the center point coordinates of the top plane of the spreader according to the plane information and the target intersection point; The first posture information of the lifting device is determined by calibrating the center point coordinates and the target intersection point.

2. The method for detecting the posture of a sling according to claim 1, characterized in that: The target intersection point is obtained based on the following steps: According to the first vector and the second vector of the top plane of the spreader and the directional relationship between the plane vectors of the plane information, vector expressions of the first vector and the second vector are obtained, wherein the first vector and the second vector are used to characterize the shape characteristics of the top plane of the spreader; The target intersection point is determined based on the vector representation of the first vector and the second vector, and the first vertex group and the second vertex group.

3. The method for detecting the posture of the spreader according to claim 2, characterized in that: In the case where the top plane of the sling is a rectangle, the first vector is perpendicular to the second vector, and the first vector and the second vector are respectively perpendicular to the plane vector, and the vector expression of the first vector and the second vector is obtained according to the directional relationship between the first vector and the second vector of the top plane of the sling and the plane vector of the plane information, including: In the case where the first vector v1 = (x1, y1, z1), the second vector v2 is defined as: v2=(y1*C-z1*B,z1*A-x1*C,x1*B-y1*A) That is: v2=v1×(A,B,C) Among them, the plane vector is (A, B, C), (A, B, C) is taken as the unit vector, and × is the vector cross product; The projection scalar of the vectors of the second vertex group P2 and P3 on the first vector v1 is a, and the projection scalar of the vectors of the first vertex group P1 and P4 on the second vector v2 is b, and we can get: A*x1+B*y1+C*z1=0 (P2-P3)·v1 / ||v1||=a (P1-P4)·v2 / ||v2||=b Wherein, · represents the dot product. When the plane vector is a unit vector, according to the property of the cross product, ||v1||=||v2|| is obtained; Among them, ||v1|| represents the 2-norm of the first vector v1, which is expressed as follows: get: F·v1=g·||v1|| Among them, F is a 3*3 constant matrix, g is a 3*1 constant matrix, and the unit vector of the first vector v1 is obtained as follows The unit vector according to the first vector A unit vector of the second vector is obtained to determine vector expressions of the first vector and the second vector.

4. The method for detecting the posture of the spreader according to claim 3, characterized in that: The target intersection includes an intersection G and an intersection H, and the determining of the target intersection based on the vector expression of the first vector and the second vector, and the first vertex group and the second vertex group includes: The intersection point G is: The intersection point H is: in, is the transpose of the first vector v1.

5. The method for detecting the posture of a sling according to claim 1, characterized in that: Determining the center point coordinates of the top plane of the sling according to the plane information and the target intersection point includes: The coordinates of the four corner points of the top plane of the sling are: C1=G+v1·a1+v2·b1 C2=C1-v2·B1 C3=C2-v1·A1 C4=C3+v2·B1 Wherein, a1 is the distance between the second calibration line and the top plane edge of the spreader, b1 is the distance between the first calibration line and the top plane edge of the spreader, and A1 and B1 are the side lengths of the top plane edge of the spreader respectively; According to the coordinates of the four corner points of the top plane of the sling, the coordinates of the center point are obtained as follows: O=C1-0.5*v2·B1-0.5*v1·A1 Among them, v1 is the first vector of the top plane of the sling, and v2 is the second vector of the top plane of the sling.

6. The method for detecting the posture of a sling according to claim 1, characterized in that: The determining the first posture information of the lifting device by using the center point coordinates and the target intersection point as calibration includes: Determine, according to the center point coordinates, the offset of the spreader in the direction of the trolley mechanism, the offset of the spreader in the direction of the trolley mechanism of the gantry crane, and the lifting height of the spreader; Determining the posture rotation angle of the spreader based on the target intersection point and the known point; The first posture information is determined according to the directional offset of the spreader on the trolley mechanism, the directional offset of the spreader on the trolley mechanism, the lifting height of the spreader, and the posture rotation angle of the spreader.

7. The method for detecting the posture of a spreader according to any one of claims 1 to 6, characterized in that: After determining the first posture information of the spreader, the method further includes: Using the first posture information as a reference, calculating the second posture information of the target container; Based on the difference between the first posture information and the second posture information, a posture deviation between the spreader and the target container is obtained.

8. The method for detecting the posture of a sling according to claim 7, characterized in that: The calculating the second posture information of the target container using the first posture information as a reference includes: Acquire third scanning data of the target container scanned by the second radar group; Determining top surface information of the target container according to the third scanning data; The second posture information is determined based on the first posture information and the top surface information.

9. The method for detecting the posture of a sling according to claim 8, characterized in that: The obtaining, based on the difference between the first posture information and the second posture information, a posture deviation between the spreader and the target container, comprises: Δx=xx, Δy=xx, Δα=α-α、 Among them, Δx, Δy, and Δα are used to characterize the deviation value of the spreader relative to the target container, which are respectively the directional offset of the trolley mechanism, the directional offset of the gantry crane's trolley mechanism, and the angular offset of rotation around the lifting direction of the spreader. The first posture information includes the offset x of the spreader in the direction of the trolley mechanism, the offset y of the spreader in the direction of the trolley mechanism, and the yaw angle α of the spreader. The second posture information includes the offset x, y, of the target container relative to the center position of the trolley mechanism, and the rotation angle α, of the target container around the lifting direction of the spreader.

10. The method for detecting the posture of a sling according to claim 7, characterized in that: After obtaining the posture deviation between the spreader and the target container, the method further includes: Based on the posture deviation, the posture of the spreader is adjusted.

Images