Loading control method of ship loader

Abstract

The invention provides a ship loader loading control method, and belongs to the technical field of ship loader control. Firstly, initial two-dimensional point cloud data, containing hatch information, of a ship is obtained based on three-dimensional laser point cloud data of the ship, then the hatch edge of the ship is recognized according to the initial two-dimensional point cloud data, then the shape and size of the hatch are obtained, the posture of a bucket-wheel stacker-reclaimer is controlled according to the shape and size of the hatch, and the loading operation of the ship loader is completed. According to the method, the two-dimensional point cloud data triangulation network with a plurality of feature triangles is constructed, and the processing calculation amount of the point cloud data is reduced while relatively many detail feature data points in the point cloud data are reserved; and meanwhile, the initial fitting straight line is set to be closer to the relative position of each data point, so that the effect of quickly approaching the optimal fitting is realized, and the problem of interference of noise on straight line fitting in the prior art can be improved by setting the preset distance.

Description

Technical Field

[0001] The invention belongs to the technical field of ship loader control, and in particular relates to a ship loader loading control method. Background Art

[0002] With the continuous development of the bulk cargo transportation industry, the traditional manual loading / unloading operation is gradually shifting towards automated loading / unloading. In the prior art, the patent with application number 202211281477.2 obtains the hatch edge by slicing, segmenting and clustering the point cloud; however, due to the limitation of the resolution of the laser radar, the slicing method easily leads to the loss of fine-grained data, thereby affecting the recognition effect of the hatch edge, and the slicing of the point cloud invisibly amplifies the interference of the point cloud noise on the hatch edge recognition. The document "Research on Bulk Cargo Hold Detection and Positioning Algorithm Based on Laser Three-Dimensional Vision" also proposes a variable rectangular frame search algorithm, which projects the point cloud onto a two-dimensional platform and then uses a rectangular frame of variable size as a search seed to search for rectangular features. However, this method requires traversing the entire point cloud data to find the search starting point. When the initial point cloud data volume is too large, the processing and calculation of the point cloud data is large, resulting in a long hatch recognition process, which does not meet the real-time requirements of the algorithm. Summary of the invention

[0003] In order to solve the problems existing in the prior art, the present invention proposes a loading control method for a ship loader to solve the problems in the prior art of low recognition accuracy of the hatch edge or hatch edge of the ship's hatch, susceptibility to noise interference, and large amount of point cloud data processing during loading control.

[0004] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a method for controlling the loading of a ship loader, comprising the following steps: S1, detecting whether the maximum detection range and the minimum division of the current laser measurement system meet the requirements, if so, executing step S2, if not, issuing a reminder signal to remind the replacement of the current laser measurement system; S2, obtaining the measurement data of the current laser measurement system, wherein the measurement data is the three-dimensional laser point cloud data of the ship; S3, projecting and transforming the three-dimensional laser point cloud data obtained in step S2 into two-dimensional data and filtering it to obtain the initial two-dimensional point cloud data of the ship containing hatch information; S4, identifying the hatch edge of the ship according to the initial two-dimensional point cloud data in step S3; S5, obtaining the hatch shape and size according to the identified hatch edge; S6, controlling the posture of the bucket wheel stacker and reclaimer based on the hatch shape and size to control the loading of the ship loader.

[0005] Furthermore, in the step S4, identifying the hatch edge of the ship specifically includes the following steps: S41: triangulating the initial two-dimensional point cloud data to obtain a two-dimensional point cloud data triangulation network containing multiple feature triangles; S42: obtaining the initial hatch boundary of the cabin based on the two-dimensional point cloud data triangulation network; S43: fitting the initial hatch boundary to identify the hatch edge of the ship.

[0006] Furthermore, in the step S41, the initial two-dimensional point cloud data is triangulated, specifically: S41-1: all points in the initial two-dimensional point cloud data are sorted according to longitude or latitude to obtain a point sequence; S41-2: a first triangle is constructed so that the first triangle contains all points in the point sequence; S41-3: the first point in the above point sequence is inserted into the first triangle to obtain three second triangles; S41-4: the second point in the above point sequence is inserted into the first triangle, if the second point is located on the edge of any of the above second triangles, the third point in the above point sequence is inserted into the first triangle, otherwise, step S41-5 is executed; S41-5: if the second point is outside the circumscribed circle of any of the second triangles, the second triangle is retained, and the other edges located in the first triangle are deleted, and then the second point is used as a vertex to continue to obtain five third triangles; S41-6: the above steps are repeated, and finally the three edges of the first triangle are removed to obtain a two-dimensional point cloud data triangulation network.

[0007] Furthermore, in step S42, the initial hatch boundary of the cabin is obtained based on the two-dimensional point cloud data triangulation network, which specifically includes the following steps: S42-1: determining the first endpoint a of the first side of any characteristic triangle in the two-dimensional point cloud data triangulation network, and the second endpoint b of the first side; S42-2: constructing a first circle with r as radius and C1 as center, so that the side of the first circle coincides with the first endpoint a and the second endpoint b, and the radius r is determined according to the following formula: , Where LT represents the net tonnage of the ship, and K1 represents the adjustment factor; The center C1 is determined according to the following formula: , where a x represents the horizontal coordinate of the first endpoint a, a y represents the ordinate of the first endpoint a, b x represents the horizontal coordinate of the second endpoint b, b y represents the ordinate of the second endpoint b, L ab represents the distance between the first endpoint a and the second endpoint b; S42-3: Construct a second circle with the above r as radius and C2 as center, so that the side of the second circle coincides with the first endpoint a and the second endpoint b: ; S42-4: Determine whether the first circle and the second circle contain any vertex of the characteristic triangle of the two-dimensional point cloud data triangulation network. If so, delete the first edge; otherwise, retain the first edge; S42-5: Continue the above steps S42-1 to S42-4, and finally determine the retained edge as the initial hatch boundary of the cabin.

[0008] Furthermore, in step S43, the initial hatch boundary is fitted to identify the hatch edge of the ship, specifically comprising the following steps: S43-1: all vertices of the edge retained in step S42-5 are divided into four sub-vertex sets PS1, PS2, PS3, and PS4; S43-2: for the sub-vertex set PS1, it is equally divided into N subsets S11-S1N; S43-3: the midpoint CS11 of the subset S11 is calculated: , Where X CS11 Indicates the horizontal coordinate of the midpoint CS11, Y CS11 Indicates the ordinate of the midpoint CS11, x 11-i represents the horizontal coordinate of the i-th point in subset S11, y 11-i represents the ordinate of the i-th point in the subset S11, and n11 represents the number of points in the subset S11; S43-4: Calculate the slope θ11 of the midpoint CS11 of the subset S11: , Where M11 represents the intermediate variable; S43-5: Use the midpoint CS11 and the slope θ11 to make a straight line as the initial fitting straight line L11 of the subset S11, and calculate the vertical distances from all points of the subset S11 to the initial fitting straight line L11; S43-6: Delete the points whose vertical distances are greater than the preset distance, and repeat the above steps S43-3 to S43-5 for the remaining points in the subset S11 until the vertical distances are all less than or equal to the preset distance; S43-7: For other subsets S12-S1N, repeat the above steps S43-2 to S43-6; S43-8: For the vertex sets PS2-PS4, repeat the above steps S43-2 to S43-7 to obtain four straight lines, connect them end to end and draw them into a rectangle-like shape, and finally obtain the identified hatch edge of the ship.

[0009] Furthermore, in step S6, based on the shape and size of the hatch, the posture of the bucket wheel stacker and reclaimer is controlled to control the loading of the ship loader. Specifically, according to the shape and size of the hatch, the ship loader is controlled to move to the position of the ship hatch, and the bucket wheel stacker and reclaimer of the ship loader is controlled to load bulk materials from the center of the cabin. First, 20% of the materials are used to cover the bottom of the cabin, and then the remaining materials are spread across the cabin in layers according to a double figure-8 route to complete the loading operation.

[0010] The beneficial technical effects of the present invention compared with the prior art are: (1) Constructing a triangulated network of two-dimensional point cloud data with multiple feature triangles, while retaining relatively more detailed feature data points in the point cloud data, it also minimizes the amount of processing and calculation of the point cloud data; (2) The initial fitting straight line is set so that it is closer to the relative position of each data point so as to achieve the effect of quickly approaching the optimal fit. By setting the preset distance, the interference problem of noise on straight line fitting in the prior art can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0012] Figure 1 The present invention is a flow chart of the ship loader loading control method. DETAILED DESCRIPTION

[0013] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, 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 creative work are within the scope of protection of the present invention.

[0014] The following first describes the concepts involved in the present application in conjunction with the accompanying drawings. It should be noted that the following description of each concept is only to make the content of the present application easier to understand, and does not limit the scope of protection of the present application; at the same time, the embodiments and features in the embodiments of the present application can be combined with each other in the absence of conflict. The present application will be described in detail with reference to the accompanying drawings and in conjunction with the embodiments.

[0015] In conjunction with the instruction manual Figure 1The present invention discloses a ship loader loading control method, which specifically comprises the following steps: S1, detecting whether the maximum detection range and the minimum division of the current laser measurement system meet the requirements, if so, executing step S2, if not, sending a reminder signal to remind to replace the current laser measurement system; the maximum detection range and the minimum division can be flexibly set according to the model of the terminal ship. The present invention preferably adopts the Horizon series laser radar, which can obtain complete ship point cloud data for most ships to meet the modeling requirements.

[0016] S2. Acquire the measurement data of the current laser measurement system, wherein the measurement data is the three-dimensional laser point cloud data of the ship; S3. Project the three-dimensional laser point cloud data obtained in step S2 into two-dimensional data and filter it to obtain the initial two-dimensional point cloud data of the ship including the hatch information. The present invention preferably adopts FIR digital filter, but Gaussian filter can also be used; S4. According to the initial two-dimensional point cloud data in step S3, identify the hatch edge of the ship; S5. According to the identified hatch edge, obtain the hatch shape and size. It should be noted that the method of the present invention is suitable for the loading control of a ship loader whose hatch is approximately rectangular; S6. Based on the hatch shape and size, control the posture of the bucket wheel stacker and reclaimer to perform the loading control of the ship loader.

[0017] In the step S4, the hatch edge of the ship is identified, which specifically includes the following steps: S41: triangulating the initial two-dimensional point cloud data to obtain a two-dimensional point cloud data triangulation network containing multiple feature triangles; S42: obtaining the initial hatch boundary of the cabin based on the two-dimensional point cloud data triangulation network; S43: fitting the initial hatch boundary to identify the hatch edge of the ship.

[0018] In the step S41, the initial two-dimensional point cloud data is triangulated, specifically: S41-1: all data points in the initial two-dimensional point cloud data are sorted according to their longitude or latitude to obtain a point sequence; S41-2: a first triangle is constructed so that the first triangle contains all points in the point sequence; S41-3: the first point in the above point sequence is inserted into the first triangle to obtain three second triangles; S41-4: the second point in the above point sequence is inserted into the first triangle, if the second point is located on the edge of any of the above second triangles, the third point in the above point sequence is inserted into the first triangle, otherwise, step S41-5 is executed; S41-5: if the second point is outside the circumscribed circle of any second triangle, the second triangle is retained, and the other edges located in the first triangle are deleted, and then the second point is used as a vertex to continue to obtain five third triangles; S41-6: the above steps are repeated, and finally the three edges of the first triangle are removed to obtain a two-dimensional point cloud data triangulation network.

[0019] In step S42, the initial hatch boundary of the cabin is obtained based on the two-dimensional point cloud data triangulation network, which specifically includes the following steps: S42-1: determining the first endpoint a of the first side of any characteristic triangle in the two-dimensional point cloud data triangulation network, and the second endpoint b of the first side; S42-2: constructing a first circle with r as radius and C1 as center, so that the side of the first circle coincides with the first endpoint a and the second endpoint b. If the radius r is set too large or too small, over-recognition is likely to occur. Therefore, the radius r needs to be determined according to the following formula: , Where LT represents the net tonnage of the ship, that is, the cargo capacity of the operational space after excluding the spaces that cannot be used for cargo; K1 represents the adjustment factor; The center C1 is determined according to the following formula: , where a x represents the horizontal coordinate of the first endpoint a, a y represents the ordinate of the first endpoint a, b x represents the horizontal coordinate of the second endpoint b, b y represents the ordinate of the second endpoint b, L ab represents the distance between the first endpoint a and the second endpoint b; S42-3: Construct a second circle with the above r as radius and C2 as center, so that the side of the second circle coincides with the first endpoint a and the second endpoint b: ; S42-4: Determine whether the first circle and the second circle contain any vertex of the characteristic triangle of the two-dimensional point cloud data triangulation network. If so, delete the first edge; otherwise, retain the first edge; S42-5: Continue the above steps S42-1 to S42-4, and finally determine the retained edge as the initial hatch boundary of the cabin.

[0020] Since the edges retained by constructing the initial hatch boundary as described above still have errors or noise, it is necessary to fit the initial hatch boundary to further reduce interference. In step S43, the initial hatch boundary is fitted to identify the hatch edge of the ship, specifically including the following steps: S43-1: Divide all vertices of the edges retained in step S42-5 into four sub-vertex sets PS1, PS2, PS3, and PS4; S43-2: For the sub-vertex set PS1, divide it into N subsets S11-S1N; S43-3: Calculate the midpoint CS11 of the subset S11: , Where X CS11Indicates the horizontal coordinate of the midpoint CS11, Y CS11 Indicates the ordinate of the midpoint CS11, x 11-i represents the horizontal coordinate of the i-th point in subset S11, y 11-i represents the ordinate of the i-th point in the subset S11, and n11 represents the number of points in the subset S11; S43-4: Calculate the slope θ11 of the midpoint CS11 of the subset S11: , Where M11 represents the intermediate variable; S43-5: Use the midpoint CS11 and the slope θ11 to make a straight line as the initial fitting straight line L11 of the subset S11, and calculate the vertical distances from all points of the subset S11 to the initial fitting straight line L11; S43-6: Delete the points whose vertical distances are greater than the preset distance, and repeat the above steps S43-3 to S43-5 for the remaining points in the subset S11 until the vertical distances are all less than or equal to the preset distance; S43-7: For other subsets S12-S1N, repeat the above steps S43-2 to S43-6; S43-8: For the vertex sets PS2-PS4, repeat the above steps S43-2 to S43-7 to obtain four straight lines, connect them end to end and draw them into a rectangle-like shape, and finally obtain the identified hatch edge of the ship.

[0021] In step S6, based on the shape and size of the hatch, the attitude of the bucket wheel stacker is controlled to control the loading of the ship loader, specifically determining the rectangular shape of the hatch, and calculating the hatch size according to the coordinates of each vertex or corner point in the identified rectangular shape; according to the shape and size of the hatch, the ship loader is controlled to move to the hatch position of the ship, and the bucket wheel stacker of the ship loader is controlled to load bulk materials from the center of the cabin, first using 20% ​​of the materials (such as ore, bulk grain and other bulk goods) to lay the bottom of the cabin, and then layering the remaining materials in the cabin according to the double 8-shaped route to complete the loading operation and ensure that the ship is not overloaded. The present invention preferably uses a PLC control system to control the attitudes of the bucket wheel stacker and reclaimer, such as the trolley position (including the trolley movement speed and forward direction), the rotation angle (controlled within plus or minus sixty degrees), and the pitch angle (controlled within ten degrees up and down), calculate the starting and ending positions and the left and right boundaries of the material pile, and realize boundary recognition during automatic material reclaiming operation.

[0022] The loading control method of the present invention not only solves the problems of low hatch edge recognition accuracy, susceptibility to noise interference, and large point cloud data processing volume in the prior art, but also can promote the development of terminal control towards full unmanned and remote control, while reducing labor costs, eliminating hidden dangers in process safety operations, and improving safety assurance.

[0023] The embodiments and / or implementation methods described above are only used to illustrate the preferred embodiments and / or implementation methods for realizing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any form. Any technical personnel in this field may make slight changes or modifications to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as technologies or embodiments that are essentially the same as the present invention.

[0024] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and its core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression and the objective existence of infinite specific structures, ordinary technicians in this technical field can make several improvements, modifications or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the concept and technical solution of the invention to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. A method for controlling loading of a ship loader, characterized in that: The ship loader loading control method comprises the following steps: S1, detect whether the maximum detection range and minimum division of the current laser measurement system meet the requirements, if so, execute step S2, if not, send a reminder signal to remind to replace the current laser measurement system; S2. Acquire measurement data of the current laser measurement system, where the measurement data is three-dimensional laser point cloud data of the ship; S3, projecting and transforming the three-dimensional laser point cloud data obtained in step S2 into two-dimensional data and filtering it to obtain initial two-dimensional point cloud data of the ship including hatch information; S4, identifying the hatch edge of the ship according to the initial two-dimensional point cloud data in step S3; S5. Obtaining a hatch shape and size according to the identified hatch edge; S6. Based on the shape and size of the hatch, the posture of the bucket wheel stacker and reclaimer is controlled to perform loading control of the ship loader.

2. The ship loader loading control method according to claim 1, characterized in that: In step S4, identifying the hatch edge of the ship specifically includes the following steps: S41: triangulating the initial two-dimensional point cloud data to obtain a two-dimensional point cloud data triangulation network including a plurality of feature triangles; S42: Based on the two-dimensional point cloud data triangulation, the initial hatch boundary of the cabin is obtained; S43: Fitting the initial hatch boundary to identify the hatch edge of the ship.

3. The method for controlling the loading of a ship loader according to claim 2, characterized in that: In step S41, the initial two-dimensional point cloud data is triangulated, specifically: S41-1: Sort all points in the initial two-dimensional point cloud data by longitude or latitude to obtain a point sequence; S41-2: construct a first triangle so that the first triangle contains all points in the point sequence; S41-3: insert the first point in the above point sequence into the first triangle to obtain three second triangles; S41-4: inserting the second point in the point sequence into the first triangle. If the second point is located on the edge of any of the second triangles, inserting the third point in the point sequence into the first triangle. Otherwise, executing step S41-5. S41-5: If the second point is outside the circumscribed circle of any second triangle, the second triangle is retained, and other edges located in the first triangle are deleted, and then the second point is used as a vertex to continue to obtain five third triangles; S41-6: Repeat the above steps, and finally remove the three edges of the first triangle to obtain a two-dimensional point cloud data triangulation network.

4. The method for controlling the loading of a ship loader according to claim 3, characterized in that: In step S42, the initial hatch boundary of the cabin is obtained based on the two-dimensional point cloud data triangulation network, which specifically includes the following steps: S42-1: Determine a first endpoint a of a first side of any characteristic triangle in a two-dimensional point cloud data triangulation network, and a second endpoint b of the first side; S42-2: construct a first circle with a radius r and a center C1, so that the side of the first circle coincides with the first endpoint a and the second endpoint b, and the radius r is determined according to the following formula: , Where LT represents the net tonnage of the ship, and K1 represents the adjustment factor; The center C1 is determined according to the following formula: ， Wherein ax represents the abscissa of the first endpoint a, ay represents the ordinate of the first endpoint a, bx represents the abscissa of the second endpoint b, by represents the ordinate of the second endpoint b, and Lab represents the distance between the first endpoint a and the second endpoint b; S42-3: Construct a second circle with the above r as radius and C2 as center, so that the side of the second circle coincides with the first endpoint a and the second endpoint b: ； S42-4: Determine whether the first circle and the second circle contain any vertex of a characteristic triangle of the two-dimensional point cloud data triangulation network; if so, delete the first edge; otherwise, retain the first edge; S42-5: Continue the above steps S42-1 to S42-4, and finally determine the retained edge as the initial hatch boundary of the cabin.

5. The ship loader loading control method according to claim 4, characterized in that: In step S43, the initial hatch boundary is fitted to identify the hatch edge of the ship, which specifically includes the following steps: S43-1: Divide all vertices of the edge retained in step S42-5 into four sub-vertex sets PS1, PS2, PS3, and PS4; S43-2: For the vertex set PS1, divide it into N subsets S11-S1N; S43-3: Calculate the midpoint CS11 of subset S11: ， Where X CS11 Indicates the horizontal coordinate of the midpoint CS11, Y CS11 Indicates the ordinate of the midpoint CS11, x 11-i represents the horizontal coordinate of the i-th point in subset S11, y 11-i represents the ordinate of the i-th point in the subset S11, and n11 represents the number of points in the subset S11; S43-4: Calculate the slope θ11 of the midpoint CS11 of the subset S11: ， Where M11 represents the intermediate variable; S43-5: Draw a straight line with the midpoint CS11 and the slope θ11 as the initial fitting straight line L11 of the subset S11, and calculate the vertical distances from all points of the subset S11 to the initial fitting straight line L11; S43-6: Delete the points whose vertical distance is greater than the preset distance, and repeat the above steps S43-3 to S43-5 for the remaining points in the subset S11 until the vertical distances are all less than or equal to the preset distance; S43-7: For other subsets S12-S1N, repeat the above steps S43-2 to S43-6; S43-8: For the vertex sets PS2-PS4, repeat the above steps S43-2 to S43-7 to obtain four straight lines, connect them end to end and draw them into a rectangle-like shape, and finally obtain the identified hatch edge of the ship.

6. The method for controlling the loading of a ship loader according to claim 5, characterized in that: In step S6, the posture of the bucket wheel stacker and reclaimer is controlled based on the shape and size of the hatch, and the loading control of the ship loader is performed. Specifically, according to the shape and size of the hatch, the ship loader is controlled to move to the position of the ship hatch, and the bucket wheel stacker and reclaimer of the ship loader is controlled to load bulk materials from the center of the cabin. First, 20% of the materials are used to cover the bottom of the cabin, and then the remaining materials are spread across the cabin in layers according to a double figure-8 route to complete the loading operation.

7. The method for controlling the loading of a ship loader according to claim 6, characterized in that: The PLC control system is used to control the posture of the bucket wheel stacker reclaimer.

8. The method for controlling the loading of a ship loader according to claim 7, characterized in that: The posture of the bucket wheel stacker and reclaimer includes the position of the trolley, the rotation angle and the pitch angle.

9. The method for controlling the loading of a ship loader according to claim 8, characterized in that: The PLC control system is used to control the position of the bucket wheel stacker and reclaimer trolley, including the trolley's running speed and forward direction.

10. The ship loader loading control method according to claim 8, characterized in that: The PLC control system is used to control the rotation angle of the bucket wheel stacker reclaimer within plus or minus sixty degrees, and the pitch angle of the bucket wheel stacker reclaimer within ten degrees.

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