Steel coil positioning, grabbing and warehousing system and its use method

Abstract

The present invention proposes a steel coil positioning, grasping, warehousing and storage system and a method of using the same, wherein a PLC control module controls a crossbeam to move horizontally along an overhead crane; the PLC control module controls a vertical descent vehicle to move perpendicularly to a horizontal plane; the vertical descent vehicle also includes a sling clamp, and the PLC control module controls the sling clamp to clamp and take and place steel coils; a main scanner is fixed at one end of the crossbeam, and a sub-scanner is fixed at the other end of the crossbeam; the main scanner and the sub-scanner acquire point cloud data of a storage area containing steel coils, and synthesize the point cloud data into a world coordinate system by calibrating parameters; point cloud data is acquired by the main scanner and the sub-scanner, with lower requirements on operators and higher accuracy; a fitting algorithm is used to calculate a conversion matrix, thereby reducing errors; the PLC control module controls the crossbeam, the vertical descent vehicle and the sling clamp, with higher grasping accuracy and significantly improved grasping efficiency; the inventory information system stores product dimensions and position coordinates, making it easier for steel coils to be put in and out of storage.

Description

Technical Field

[0001] The present invention relates to the technical field of handling systems, and in particular to a steel coil positioning, grabbing, taking out and warehousing system and a use method thereof. Background Art

[0002] With the development of science and technology, automated operation is a trend of technological development and an important way and means for efficient operation of warehousing operations. It includes an automatic operation system for overhead cranes, a material management system for the warehouse area, and automatic in / out and operation control systems. Warehouse managers use mechanized equipment to control the handling and shipment of goods. Operators observe the location of goods in the control room through the handling grippers and the supporting video equipment, and use the grab bucket on the gantry crane to grab them. Warehouse managers do not need to go to the warehouse site, which saves labor costs and greatly improves the working environment of warehouse managers. However, the entire operation process is to grab the goods with images transmitted by the video equipment supporting the grippers. The system has high requirements for warehouse managers to operate the grippers, low grabbing efficiency, and low grabbing accuracy. Once the product requires anti-fall or has a large volume or mass, it is easy to cause grabbing accidents.

[0003] Secondly, warehouse managers need to manually enter the grabbing information after completing the retrieval or warehousing. When there are many types of products entering or leaving the warehouse, it is easy to confuse the product entry and exit information. When the number of products entering and leaving the warehouse is large, counting deviations are likely to occur, resulting in the number not matching the actual situation.

[0004] Therefore, the warehouse management system for automated in-and-out grabbing of steel coils requires a grabbing and positioning system with high grabbing efficiency, high grabbing accuracy, low grabbing difficulty, and the ability to automatically input in-and-out information. Summary of the invention

[0005] In view of this, the present invention proposes a steel coil positioning, grasping, warehousing and storage system and a method of using the same. The grasping and positioning system has high grasping efficiency and success rate and low grasping difficulty.

[0006] The technical solution of the present invention is implemented as follows: a steel coil positioning, grabbing and warehousing system includes an overhead crane, a scanning device, a PLC control module, an algorithm module and an inventory information system, wherein the overhead crane includes a beam and a vertical drop vehicle; the PLC control module controls the horizontal movement of the beam along the overhead crane; the PLC control module controls the vertical drop vehicle to move perpendicular to the horizontal plane; the vertical drop vehicle also includes a sling clamp, the sling clamp clamps the steel coil, and the PLC control module controls the sling clamp to clamp and put the steel coil; the scanning device includes a main scanner and a sub-scanner, the main scanner is fixed at one end of the beam, and the sub-scanner is fixed at the other end of the beam; the main scanner and the sub-scanner obtain the point cloud data of the warehouse area containing the steel coil, and at the same time synthesize the point cloud data into the world coordinate system through calibration parameters; the main scanner and the sub-scanner transmit the point cloud data of the warehouse area to the algorithm module; the algorithm module calculates the coordinate points of the steel coil in the world coordinate system and the size of the steel coil, and transmits the coordinate points in the world coordinate system to the PLC control module and the inventory information system; the inventory information system records the warehousing and warehousing information of the steel coil of this size.

[0007] On the basis of the above technical solution, preferably, the rappelling vehicle further includes a laser sensor, and the laser sensor is fixedly arranged on the sling clamp.

[0008] How to use the steel coil positioning, grabbing and warehousing system:

[0009] S1, synthetic point cloud data:

[0010] The point cloud data obtained by the auxiliary scanner is converted into the coordinate system formed by the point cloud data of the main scanner, and two point cloud data are synthesized;

[0011] S2, establish the world coordinate system:

[0012] The initial positions of the beam and the rappelling vehicle are the origins of the X-axis and Y-axis, and the ground is the origin of the Z-axis. At this time, the direction in which the beam moves horizontally is the positive direction of the X-axis, the direction in which the rappelling vehicle moves on the beam is the positive direction of the Y-axis, and the direction away from the ground is the positive direction of the Z-axis.

[0013] And convert the point cloud data synthesized by S1 into world coordinates.

[0014] S3, determine the rotation matrix from the main scanner to the world coordinate system:

[0015] The main scanner and the auxiliary scanner scan the position of the wall in the warehouse. The algorithm module obtains the point cloud data scanned by the main scanner and the auxiliary scanner, extracts the ground point cloud ground, fits it into a plane, obtains the unit normal vector normal, calculates the angle angle between the normal vector and the positive direction of the Z axis, makes the ground perpendicular to the Z axis, and obtains a rotation axis and a specified rotation angle.

[0016] Axis axis = normal × UnitZ

[0017] Angle angle = acos(normal·UnitZ)

[0018] Align the point cloud data to the XOY plane of the world coordinate system after selecting the angle angle for axis. Similarly, another plane rotation matrix is ​​obtained.

[0019] Select a feature area in the point cloud data, fit the feature points, use the measuring equipment to measure the coordinates of the feature points in the world coordinate system, compare the offsets of the two feature points, and subtract them to obtain the translation vector and the transformation matrix Mat_world converted to the world coordinates.

[0020] S4, main scanner and sub-scanner calibration:

[0021] The point cloud data of the secondary scanner is converted to the main scanner coordinate system, and the main scanner point cloud cloud_primary and the secondary scanner point cloud cloud_sub are read at the same time. After obtaining the overlapping area, the ICP algorithm is used to fit the point cloud transformation matrix Mat_primary. The transformation matrix of the secondary scanner point cloud to the world coordinate system is Mat=Mat_world×Mat_primary.

[0022] S5, steel coil point cloud data fitting:

[0023] Obtain the target steel coil point cloud data, use straight-through filtering to cut the point cloud data, separate the central point cloud data and the surrounding steel coil point cloud data, and separate the steel coil point cloud data and the point cloud data of the four surrounding steel coils;

[0024] Cluster segmentation and Gaussian filtering are used to eliminate discrete points and obtain valid steel coil point cloud data. The point cloud data is fitted into a cylinder using a fitting algorithm. After removing the erroneous data with large deviation and radius out of range, the radius of the steel coil and the equation of the center line lineCenter are extracted. The length of the steel coil is extracted. The length direction of the steel coil is parallel to the X-axis. The plane where the center point is located is planeCenter. minX and maxX are the minimum and maximum values ​​of the steel coil in the X-axis direction, respectively. x= (minX+maxX)×0.5 is the plane equation of the plane where the center point is located. The intersection of the line lineCenter and the plane planeCenter is calculated as the coordinates of the center point of the steel coil. The length, width, radius value and center point coordinate information of the steel coil (6) are calculated and obtained.

[0025] S6, warehousing operation:

[0026] The size of the steel coil is input into the inventory information system, and the inventory information system transmits the information to the main scanner and the sub-scanner. The main scanner and the sub-scanner obtain the world coordinate point of the steel coil, the world coordinate point of the beam and the vertical drop vehicle, and the world coordinate point of the placement position of the steel coil, and send the above world coordinate points to the PLC control module. The PLC control module controls the beam and the vertical drop vehicle to reach the world coordinate point of the steel coil, clamps the steel coil with the sling clamp, and transfers it to the world coordinate point of the placement position.

[0027] S7, outbound operation:

[0028] The size of the steel coil is input into the inventory information system. The inventory information system transmits the world coordinate point of the outbound steel coil, the world coordinate point of the beam and the vertical drop vehicle to the PLC control module. The PLC control module controls the beam and the vertical drop vehicle to reach the world coordinate point of the steel coil, and clamps the steel coil with the sling clamp to complete the outbound delivery.

[0029] The steel coil positioning, grabbing and warehousing system and its use method of the present invention have the following beneficial effects compared with the prior art:

[0030] The point cloud data is obtained by the main scanner and the auxiliary scanner, which has low requirements on operators and high accuracy;

[0031] The fitting algorithm is used to calculate the transformation matrix, which reduces the error;

[0032] The PLC control module controls the crossbeam, rappelling vehicle and spreader clamp, which has higher grasping accuracy and significantly improved grasping efficiency;

[0033] The inventory information system saves the product's dimensions and location coordinates, making it easier to move coils in and out of storage. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 This is a flow chart of the steel coil positioning, grabbing and warehousing system of the present invention. DETAILED DESCRIPTION

[0036] The following will be combined with 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.

[0037] like Figure 1 As shown, the steel coil positioning, grabbing and warehousing system includes an overhead crane 1, a scanning device 2, a PLC control module 3, an algorithm module 4 and an inventory information system 5.

[0038] The overhead crane 1 includes a cross beam 11 and a vertical descending vehicle 12 .

[0039] The PLC control module 3 controls the cross beam 11 to move horizontally along the overhead crane 1 , and the PLC control module 3 controls the vertical descending vehicle 12 to move vertically to the horizontal plane.

[0040] The vertical drop vehicle 12 further includes a sling clamp 121 , on which the steel coil 6 is clamped. The PLC control module 3 controls the sling clamp 121 to clamp and place the steel coil 6 .

[0041] The scanning device 2 includes a main scanner 21 and a sub-scanner 22 . The main scanner 21 is fixedly disposed at one end of the beam 11 , and the sub-scanner 22 is fixedly disposed at the other end of the beam 11 .

[0042] The main scanner 21 and the sub-scanner 22 acquire the point cloud data of the storage area containing the steel coil 6 and the point cloud data of the steel coil 6, and synthesize the point cloud data into the world coordinate system through calibration parameters.

[0043] The main scanner 21 and the sub-scanner 22 transmit the point cloud data of the warehouse area and the point cloud data of the steel coil 6 to the algorithm module 4 .

[0044] The algorithm module 4 calculates the coordinate point of the steel coil 6 in the world coordinate system and the size of the steel coil 6, and transmits the coordinate point in the world coordinate system to the PLC control module 3 and the inventory information system 5. The inventory information system 5 records the in-and-out information of the steel coil 6 of this size.

[0045] In order to improve the grabbing efficiency of the spreader clamp 121, a preferred embodiment is that the vertical drop vehicle 12 further includes a laser sensor 122, and the laser sensor 122 is fixedly arranged on the spreader clamp 121. The relative position of the spreader clamp 121 and the steel coil 6 is determined by the laser sensor 122 to ensure the reliability of grabbing.

[0046] The following describes the use of the steel coil positioning, grabbing and warehousing system of the present invention:

[0047] S1, synthetic point cloud data:

[0048] The point cloud data obtained by the auxiliary scanner 22 is converted into the coordinate system formed by the point cloud data of the main scanner 21, and two point cloud data are synthesized;

[0049] S2, establish the world coordinate system:

[0050] The initial positions of the beam 11 and the rappelling vehicle 12 are the origins of the X-axis and the Y-axis in the world coordinate system, and the ground is the origin of the Z-axis in the world coordinate system. At this time, the horizontal moving direction of the beam 11 is the positive direction of the X-axis, the moving direction of the rappelling vehicle 12 on the beam 11 is the positive direction of the Y-axis, and the direction away from the ground is the positive direction of the Z-axis;

[0051] And convert the point cloud data synthesized by S1 into world coordinates;

[0052] S3, determine the rotation matrix of the main scanner 21 to the world coordinate system:

[0053] The main scanner 21 and the auxiliary scanner 22 scan the position of the wall in the warehouse. The algorithm module 4 obtains the point cloud data scanned by the main scanner 21 and the auxiliary scanner 22, extracts the ground point cloud ground, fits it into a plane, obtains the unit normal vector normal, calculates the angle angle between the normal vector and the positive direction of the Z axis, and the ground is perpendicular to the Z axis, and obtains a rotation axis and a specified rotation angle.

[0054] Axis axis = normal × UnitZ

[0055] Angle angle = acos(normal·UnitZ)

[0056] Align the point cloud data to the XOY plane of the world coordinate system after selecting the angle angle for axis. Similarly, another plane rotation matrix is ​​obtained.

[0057] Select a feature area in the point cloud data, fit the feature points, use the measuring equipment to measure the coordinates of the feature points in the world coordinate system, compare the offsets of the two feature points, subtract the coordinates of the two feature points to obtain the translation vector and the transformation matrix Mat_world converted to the world coordinates;

[0058] S4, calibration of the main scanner 21 and the auxiliary scanner 22:

[0059] The point cloud data of the secondary scanner 22 is converted to the coordinate system of the main scanner 21. The point cloud cloud_primary of the main scanner 21 and the point cloud cloud_sub of the secondary scanner 22 are read at the same time. After obtaining the overlapping area, the ICP algorithm is used to fit the point cloud conversion matrix Mat_primary. The conversion matrix of the point cloud of the secondary scanner 22 to the world coordinate system is Mat=Mat_world×Mat_primary.

[0060] S5, steel coil 6 point cloud data fitting:

[0061] The point cloud data of the target steel coil 6 is obtained, and the point cloud data is cut using a straight-through filter to segment the central point cloud data and the point cloud data of the surrounding steel coils, and the point cloud data of the steel coil 6 and the point cloud data of the four surrounding steel coils 6 are segmented;

[0062] Use clustering segmentation and Gaussian filtering to eliminate discrete points and obtain valid point cloud data of steel coil 6. Then use the fitting algorithm to fit the point cloud data into a cylinder, remove erroneous data with excessive deviation and radius out of range, extract the radius of steel coil 6 and the equation of the center line lineCenter. The length direction of steel coil 6 is parallel to the X-axis. Extract the length of steel coil 6. The plane where the center point of steel coil 6 is located is planeCenter. minX and maxX are the minimum and maximum values ​​of the X-axis direction of steel coil 6 respectively. x= (minX+maxX)×0.5 is the plane equation of the plane planeCenter where the center point is located. Calculate the intersection of the line lineCenter and the plane planeCenter to obtain the coordinates of the center point of steel coil 6; Calculate and obtain the length, width, radius value and center point coordinate information of steel coil (6);

[0063] S6, warehousing operation:

[0064] The size of the steel coil 6 is input to the inventory information system 5, and the inventory information system 5 transmits the information to the main scanner 21 and the sub-scanner 22. The main scanner 21 and the sub-scanner 22 obtain the world coordinate point of the steel coil 6, the world coordinate point of the beam 11 and the vertical drop vehicle 12, and the world coordinate point of the placement position of the steel coil 6, and send the above world coordinate point to the PLC control module 3. The PLC control module 3 controls the beam 11 and the vertical drop vehicle 12 to reach the world coordinate point of the steel coil 6, clamps the steel coil 6 through the sling clamp 121, and transfers it to the world coordinate point of the placement position; the laser sensor 122 calibrates the sling clamp 121;

[0065] S7, outbound operation:

[0066] The size of the steel coil 6 is input into the inventory information system 5. The inventory information system 5 transmits the world coordinate point of the outbound steel coil 6, the world coordinate point of the beam 11 and the vertical drop vehicle 12 to the PLC control module 3. The PLC control module 3 controls the beam 11 and the vertical drop vehicle 12 to reach the world coordinate point of the steel coil 6. The laser sensor 122 calibrates the sling clamp 121. The steel coil 6 is clamped by the sling clamp 121 to complete the outbound delivery.

[0067] During the warehousing and outbound operations, the algorithm module 4 needs to calculate the distance between adjacent steel coils 6 and the effective grabbing points of the sling clamp 121, the world coordinate points of the beam 11 and the vertical drop vehicle 12, and calculate whether a collision will occur and whether the operation can continue. If the operation cannot continue, a warning message will be issued and manual intervention will be initiated.

[0068] When grabbing the steel coil 6, the target position has the information of the steel coil 6. At the same time, in the Y-axis direction, the distance between the hanger clamp 121 and the steel coil 6 can meet the working distance of the hanger clamp 121. Through the calculation of the algorithm module 4, the hanger clamp 121 is opened to an appropriate width, the hanger clamp 121 moves to the target position, and when the laser emitted by the laser sensor 122 is not blocked for 0.5 to 1 second, the hanger clamp 121 is closed to complete the grabbing.

[0069] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for using a steel coil positioning, grabbing, taking-in and taking-out storage system, the steel coil positioning, grabbing, taking-in and taking-out storage system comprising an overhead crane (1), a scanning device (2), a PLC control module (3), an algorithm module (4) and an inventory information system (5), wherein: Features: The overhead crane (1) comprises a crossbeam (11) and a vertical descending vehicle (12); The PLC control module (3) controls the crossbeam (11) to move along the plane where the overhead crane (1) is located; The PLC control module (3) controls the vertical drop vehicle (12) to move perpendicular to the plane; The vertical drop vehicle (12) further comprises a sling clamp (121), on which a steel coil (6) is clamped, and a PLC control module (3) controls the sling clamp (121) to clamp and place the steel coil (6); The scanning device (2) comprises a main scanner (21) and a sub-scanner (22), wherein the main scanner (21) is fixedly arranged at one end of the crossbeam (11), and the sub-scanner (22) is fixedly arranged at the other end of the crossbeam (11); The main scanner (21) and the auxiliary scanner (22) acquire point cloud data of the storage area containing the steel coil (6) and point cloud data of the steel coil (6), and synthesize the point cloud data into a world coordinate system by calibrating parameters; The main scanner (21) and the auxiliary scanner (22) transmit the point cloud data of the warehouse area and the point cloud data of the steel coil (6) to the algorithm module (4); The algorithm module (4) calculates the coordinate points of the steel coil (6) in the world coordinate system and the size of the steel coil (6), and transmits the coordinate points in the world coordinate system to the PLC control module (3) and the inventory information system (5); The inventory information system (5) records the in-and-out information of the steel coil (6) of the size; The vertical drop vehicle (12) further comprises a laser sensor (122), wherein the laser sensor (122) is fixedly arranged on the hanger clamp (121); The method for using the steel coil positioning, grabbing and warehousing system comprises the following steps: Synthetic point cloud data: The point cloud data obtained by the auxiliary scanner (22) is converted into a coordinate system formed by the point cloud data of the main scanner (21), and two point cloud data are synthesized; Establish the world coordinate system: The initial positions of the crossbeam (11) and the vertical drop vehicle (12) are the origins of the X-axis and the Y-axis in the world coordinate system, and the ground is the origin of the Z-axis in the world coordinate system. At this time, the direction in which the crossbeam (11) moves horizontally is the positive direction of the X-axis, the direction in which the vertical drop vehicle (12) moves on the crossbeam (11) is the positive direction of the Y-axis, and the direction away from the ground is the positive direction of the Z-axis. And convert the point cloud data synthesized by S1 into world coordinates; Determine the rotation matrix of the main scanner (21) to the world coordinate system: The main scanner (21) and the auxiliary scanner (22) scan the position of the wall in the warehouse. The algorithm module (4) obtains the point cloud data scanned by the main scanner (21) and the auxiliary scanner (22), extracts the ground point cloud ground, fits it into a plane, obtains the unit normal vector normal, calculates the angle angle between the normal vector and the positive direction of the Z axis, and obtains a rotation axis and a specified rotation angle. Axis axis = normal × UnitZ Angle angle = acos(normal·UnitZ) Align the point cloud data to the XOY plane of the world coordinate system after selecting the angle angle for axis. Similarly, another plane rotation matrix is ​​obtained. Select a feature area in the point cloud data, fit the feature points, use the measuring equipment to measure the coordinates of the feature points in the world coordinate system, compare the offsets of the two feature points, subtract the coordinates of the two feature points to obtain the translation vector and the transformation matrix Mat_world converted to the world coordinates; The main scanner (21) and the auxiliary scanner (22) are calibrated: The point cloud data of the secondary scanner (22) is converted to the coordinate system of the main scanner (21), and the point cloud cloud_primary of the main scanner (21) and the point cloud cloud_sub of the secondary scanner (22) are read at the same time. After obtaining the overlapping area, the ICP algorithm is used to fit the point cloud transformation matrix Mat_primary. The transformation matrix of the point cloud of the secondary scanner (22) to the world coordinate system is Mat=Mat_world×Mat_primary; The point cloud data fitting of the steel coil (6): Obtain the point cloud data of the target steel coil (6), use straight-through filtering to cut the point cloud data, separate the central point cloud data and the point cloud data of the surrounding steel coils, and separate the point cloud data of the steel coil (6) and the point cloud data of the four surrounding steel coils (6); Cluster segmentation and Gaussian filtering are used to eliminate discrete points and obtain valid steel coil (6) point cloud data. Then, a fitting algorithm is used to fit the point cloud data into a cylinder to remove erroneous data with excessive deviation and radius out of range. The radius of the steel coil (6) and the center line equation lineCenter are extracted. The length direction of the steel coil (6) is parallel to the X-axis. The length of the steel coil (6) is extracted. The plane where the center point of the steel coil (6) is located is planeCenter. minX and maxX are the minimum and maximum values ​​of the steel coil (6) in the X-axis direction, respectively. x= (minX+maxX)×0.5 is the plane equation of the plane where the center point is located. The intersection of the line lineCenter and the plane planeCenter is calculated to be the coordinates of the center point of the steel coil (6). The length, width, radius value and center point coordinate information of the steel coil (6) are calculated and obtained. The warehousing operation: The size of the steel coil (6) is input into the inventory information system (5), and the inventory information system (5) transmits the information to the main scanner (21) and the sub-scanner (22). The main scanner (21) and the sub-scanner (22) obtain the world coordinate point of the steel coil (6), the world coordinate point of the beam (11) and the vertical drop vehicle (12), and the world coordinate point of the placement position of the steel coil (6), and send the above world coordinate point to the PLC control module (3). The PLC control module (3) controls the beam (11) and the vertical drop vehicle (12) to reach the world coordinate point of the steel coil (6), clamps the steel coil (6) through the sling clamp (121), and transfers it to the world coordinate point of the placement position; the laser sensor (122) calibrates the sling clamp (121).

2. The method for using the steel coil positioning, grabbing and warehousing system according to claim 1, characterized in that: Outbound operation: The size of the steel coil (6) is input into the inventory information system (5), and the inventory information system (5) transmits the world coordinate point of the steel coil (6) to be shipped out, the world coordinate point of the beam (11) and the vertical drop vehicle (12), to the PLC control module (3), and the PLC control module (3) controls the beam (11) and the vertical drop vehicle (12) to reach the world coordinate point of the steel coil (6), and the laser sensor (122) calibrates the sling clamp (121); the steel coil (6) is clamped by the sling clamp (121) to complete the shipment.

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