An unmanned scrap grabber grabbing system and method for a bar-shaped scrap

Abstract

This invention relates to an unmanned steel grabber system and method for grasping strip-shaped scrap steel, belonging to the field of automation. The method involves: pre-processing the strip-shaped scrap steel before grasping; using a sensing system to select strip-shaped scrap steel with lengths within a certain deviation range; calculating the center of gravity of the strip-shaped scrap steel; arranging the strip-shaped scrap steel closely in the same direction with their center of gravity aligned in a straight line; then, the end effector grasps all the strip-shaped scrap steel at their center of gravity, and the working arm is raised until all the strip-shaped scrap steel is suspended in the air; finally, the working arm is swung, and ground sensing sensors detect whether the center of gravity has shifted outside the stable range. This invention enhances the stability of the unmanned steel grabber in grasping strip-shaped scrap steel, increases the success rate of the grasping process and the safety during operation, improves work efficiency, and reduces the hazards to equipment and personnel caused by the strip-shaped scrap steel shifting or slipping during the movement of the working arm.

Description

Technical Field

[0001] This invention belongs to the field of automation and relates to an unmanned steel grabbing system and method for grabbing strip-shaped scrap steel. Background Technology

[0002] Strips of scrap steel vary in length, thickness, and shape. Existing scrap steel production lines require highly skilled operators to handle these strips; otherwise, the scrap steel can easily slip during handling, causing equipment or personnel injury, or shift, making placement in the production equipment more difficult. Unmanned scrap steel handling presents a significant challenge in ensuring the success rate and stability of strip-shaped scrap steel handling. Summary of the Invention

[0003] In view of this, the purpose of this invention is to provide an unmanned steel grabbing system and method for grabbing strip-shaped scrap steel. Before grabbing, the strip-shaped scrap steel is pre-processed. A sensing system selects strip-shaped scrap steel with lengths within a certain deviation range, calculates the center of gravity of the strip-shaped scrap steel, and arranges the strip-shaped scrap steel closely in the same direction with their center of gravity on a straight line. Then, the end effector grabs all the strip-shaped scrap steel at the center of gravity, and the working arm is raised until all the strip-shaped scrap steel is suspended in the air. Finally, the working arm is swung, and a ground sensing sensor detects whether the center of gravity has shifted outside the stable range. If so, the working arm is lowered, the end effector is released, and the grabbing, swaying, and detection of the strip-shaped scrap steel is repeated; if not, the working arm is moved to operate normally.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] An unmanned steel grabbing system for strip-shaped scrap steel, the system comprising sensors, a data acquisition module, a data processing module and a control unit connected in sequence;

[0006] The data acquisition module collects data on the strip-shaped scrap steel through sensors and sends it to the data processing module.

[0007] The data processing module includes a center of gravity calculation submodule, a center of gravity detection submodule, and a process control submodule;

[0008] The center of gravity calculation submodule receives a request from the process control submodule and calculates the center of gravity of the strip scrap steel.

[0009] ① For scrap steel with the same cross-sectional size, the center point is taken as the center of gravity;

[0010] ②The algorithm for calculating the centroid of cross-sections with different sizes and tetrahedral shapes is as follows;

[0011] The cross-section of the strip of scrap steel is divided into vertices (x0, y0), (x1, y1)...(x n-1 ,y n-1 The centroid of the polygon defined is (C).x C y ),in,

[0012]

[0013]

[0014] A is the area of ​​the polygon:

[0015]

[0016] In three-dimensional space, the centroid of a tetrahedron is its four vertices (x, y, z). i ,y i ,z i Arithmetic mean of 1 / 2 1 / 3 ...

[0017]

[0018]

[0019]

[0020] The center of gravity is (C x C y C z );

[0021] ③ For strip-shaped scrap steel with different cross-sectional sizes and polyhedral shapes, the centroid calculation method is as follows:

[0022] The polyhedron is tetrahedralized, and then the barycenter coordinates of the tetrahedrons are averaged by volume weighting to obtain n tetrahedrons. The barycenters are represented by three-dimensional vectors, namely... The volumes are V1...V n The center of gravity is:

[0023]

[0024] The final calculated center of gravity is returned to the process control submodule;

[0025] The center of gravity detection submodule receives a request from the process control submodule after the grabbing is complete, and detects the three-dimensional coordinates of the center of gravity of the grabbed strip of scrap steel: P1(x1,y1,z1), and the relative coordinates of the end effector: P0(x0,y0,z0). The distance between the two points is... After the end effector vibrates, a request is received from the process control submodule to detect the three-dimensional coordinates of the center of gravity of the strip scrap steel, P2(x2,y2,z2), and the three-dimensional coordinates of the end effector, P4(x4,y4,z4). The distance between the two points is... Calculate the offset Δd = d2 - d1 and return it to the process control submodule;

[0026] The process control submodule sends requests to the center of gravity calculation submodule and the center of gravity detection submodule, and formulates a control process based on the returned calculation results and outputs it to the control unit.

[0027] The unmanned steel grabber method for grabbing strip-shaped scrap steel based on the system includes the following steps:

[0028] S0: Initiate a data scraping task;

[0029] S1: Sensor scans strip-shaped scrap steel pile;

[0030] S2: The process control submodule requests the center of gravity calculation submodule using the scanned sensing data. The center of gravity calculation submodule calculates the center of gravity of the strip scrap steel based on the sensing data and returns it to the process control submodule.

[0031] S3: The process control submodule uses the center of gravity position as the grab point, calculates the pre-processing placement point, arranges the strip scrap steel according to the center of gravity position, formulates the control process, and outputs it to the control unit.

[0032] S4: The end effector of the steel grabber grabs a strip of scrap steel at the center of gravity and moves it to the pre-treatment placement point;

[0033] S5: Repeat S4 to make the strips of scrap steel overlap and their centers of gravity be in a straight line until the weight threshold is reached. The end effector has a weighing sensor to obtain the weight of the gripped material.

[0034] S6: The end effector grabs all the pre-treated strips of scrap steel, moves the working arm, and raises the end effector in a straight line until all the strips of scrap steel are suspended in the air and reach a certain height;

[0035] S7: Shake the end effector to obtain the current sensing data of the strip scrap steel through the sensor. The process control submodule uses the sensing data to request the center of gravity detection submodule. The center of gravity detection submodule calculates the offset and returns it to the process control submodule.

[0036] S8: The process control submodule formulates a control process based on the comparison results of the offset and the threshold: if the threshold is exceeded, it indicates that the gripping is unstable, and the control process is sent to the control unit, the steel grabber lowers its working arm, releases the grabbed strip of scrap steel, and executes S3; if the threshold is within the range, it indicates that the gripping is stable, and the control process is sent to the control unit, so that the steel grabber moves its working arm to continue working.

[0037] The beneficial effects of this invention are: it enhances the stability of the unmanned steel grabber in grabbing strip scrap steel, increases the success rate of the unmanned steel grabber in grabbing and the safety during operation, improves the operation efficiency, and reduces the harm to equipment and personnel caused by the deviation or slippage of strip scrap steel when the working arm moves.

[0038] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0039] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0040] Figure 1 This is a system structure diagram of the present invention;

[0041] Figure 2 This is a flowchart of the method of the present invention;

[0042] Figure 3 This is a schematic diagram showing the arrangement of the center of gravity positions of the strip-shaped scrap steel in this invention. Detailed Implementation

[0043] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0044] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0045] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0046] like Figure 1 As shown, the grasping system includes sensors, a data acquisition module, a data processing module, and a control unit connected in sequence; the data processing module includes a center of gravity calculation submodule, a center of gravity detection submodule, and a process control submodule.

[0047] 1) The data acquisition module collects data on strip-shaped scrap steel through ground and vehicle-mounted sensing sensors, providing data support for other modules.

[0048] 2) Data processing module:

[0049] A. The center of gravity calculation submodule receives requests (including sensing data) from the process control submodule and calculates the center of gravity of the strip scrap steel:

[0050] ① For scrap steel with the same cross-sectional size, the center point is taken as the center of gravity;

[0051] ② For cross-sections of different sizes and in tetrahedral shape (the unscanned faces are estimated based on the scanned faces), the centroid calculation algorithm is as follows;

[0052] The cross-section of the strip-shaped scrap steel has several vertices (x0, y0), (x1, y1)...(x n-1 ,y n-1 The centroid of the polygon defined is (C). x C y ),in,

[0053]

[0054]

[0055] A is the area of ​​the polygon (with a symbol);

[0056]

[0057] In three-dimensional space, the centroid of a tetrahedron is its four vertices (x, y, z). i ,y i ,z i Arithmetic mean of 1 / 2 1 / 3 ...

[0058]

[0059]

[0060]

[0061] The center of gravity is (C x C y C z );

[0062] ③ For strip-shaped scrap steel with different cross-sectional sizes and polyhedral shapes, the centroid calculation method is as follows:

[0063] The polyhedron is tetrahedralized, and then the centroid coordinates of the tetrahedrons are averaged by volume to obtain n tetrahedrons, with their centroids being (three-dimensional vectors). The volumes are V1...V n The center of gravity is:

[0064]

[0065] The final calculated center of gravity is returned to the process control submodule.

[0066] B. The center of gravity detection submodule receives a request (including sensing data) from the process control submodule after the grabbing is complete. It detects the three-dimensional coordinates of the center of gravity of the grabbed strip of scrap steel: P1(x1,y1,z1), and the relative coordinates of the end effector: P0(x0,y0,z0). The distance between the two points is... After the end effector shakes, it receives a request (including sensing data) from the process control submodule, detects the three-dimensional coordinates of the center of gravity of the strip scrap steel P2(x2,y2,z2), and the three-dimensional coordinates of the end effector P4(x4,y4,z4), with a distance between the two points. Calculate the offset Δd = d2 - d1 and return it to the process control submodule.

[0067] C. The process control submodule requests the center of gravity calculation submodule and the center of gravity detection submodule, and formulates a control process output to the control unit based on the returned calculation results.

[0068] like Figure 2 As shown, the scraping method is as follows:

[0069] S0: Initiate a data scraping task;

[0070] S1: Ground and vehicle-mounted sensing sensors scan the strip-shaped scrap steel pile;

[0071] S2: The process control submodule requests the center of gravity calculation submodule using the scanned sensing data. The center of gravity calculation submodule calculates the center of gravity of the strip scrap steel based on the sensing data and returns it to the process control submodule.

[0072] S3: The process control submodule uses the center of gravity position as the grab point and calculates preprocessing (arranging the strip scrap steel according to the center of gravity position, such as...). Figure 3 (As shown) Placement point, define control flow, and output to control unit;

[0073] S4: The end effector of the steel grabber grabs a strip of scrap steel at the center of gravity and moves it to the pre-treatment placement point;

[0074] S5: Repeat S4 to make the strips of scrap steel overlap tightly and the center of gravity converge in a straight line as much as possible until the weight threshold is reached (the end effector has a weighing sensor to obtain the weight of the gripped material).

[0075] S6: The end effector grabs all the pre-treated strips of scrap steel, moves the working arm, and raises the end effector in a straight line until all the strips of scrap steel are suspended in the air and reach a safe height (to prevent the strips of scrap steel from swaying and hitting the ground).

[0076] S7: Shake the end effector to obtain the current sensing data of the strip scrap steel through ground and vehicle-mounted sensing sensors. The process control submodule uses the sensing data to request the center of gravity detection submodule. The center of gravity detection submodule calculates the offset and returns it to the process control submodule.

[0077] S8: The process control submodule formulates a control process based on the comparison results of the offset and the threshold: if the threshold is exceeded, it indicates that the gripping is unstable, and the control process is sent to the control unit, the steel grabber lowers its working arm, releases the grabbed strip of scrap steel, and executes S3; if the threshold is within the range, it indicates that the gripping is stable, and the control process is sent to the control unit, so that the steel grabber moves its working arm to continue working.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A non-manual steel grabbing system for strip-shaped scrap steel, characterized in that: The system includes a sensor, a data acquisition module, a data processing module, and a control unit connected in sequence. The data acquisition module collects data on the strip-shaped scrap steel through sensors and sends it to the data processing module. The data processing module includes a center of gravity calculation submodule, a center of gravity detection submodule, and a process control submodule; The center of gravity calculation submodule receives a request from the process control submodule and calculates the center of gravity of the strip scrap steel. ① For scrap steel with the same cross-sectional size, the center point is taken as the center of gravity; ②The algorithm for calculating the centroid of cross-sections with different sizes and tetrahedral shapes is as follows; The cross-section of the strip of scrap steel consists of various vertices. The centroid of the defined polygon is ,in, A is the area of ​​the polygon: In three-dimensional space, the center of gravity of a tetrahedron is its four vertices. Arithmetic mean: Center of gravity ; ③ For strip-shaped scrap steel with different cross-sectional sizes and polyhedral shapes, the centroid calculation method is as follows: The polyhedron is tetrahedralized, and then the barycenter coordinates of the tetrahedrons are averaged by volume weighting to obtain n tetrahedrons. The barycenters are represented by three-dimensional vectors, namely... The volumes are respectively The center of gravity is: The final calculated center of gravity is returned to the process control submodule; After the grabbing is completed, the center of gravity detection submodule receives a request from the process control submodule to detect the three-dimensional coordinates of the center of gravity of the grabbed strip of scrap steel. Relative coordinates of the end effector The distance between the two points is After the end effector shakes, it receives a request from the process control submodule to detect the three-dimensional coordinates of the center of gravity of the strip of scrap steel. Three-dimensional coordinates of the end effector The distance between the two points is Calculate the offset And return to the process control submodule; The process control submodule sends requests to the center of gravity calculation submodule and the center of gravity detection submodule, and formulates a control process based on the returned calculation results and outputs it to the control unit. The process control submodule uses the center of gravity position returned by the center of gravity calculation submodule as the grab point, calculates the pre-processing placement point, and arranges the strips of scrap steel according to the center of gravity position until the weight threshold is reached; the process control submodule then calculates the offset based on the offset. Based on the comparison results with the threshold, a control process is established: when the offset... When the threshold is exceeded, the control process is sent to the control unit to lower the working arm of the steel grabber and release the grabbed strip of scrap steel. The steps of using the center of gravity position as the grabbing point, calculating the pre-processing placement point, and arranging the strip of scrap steel according to the center of gravity position are repeated. When offset When the threshold is within the specified range, a control procedure is sent to the control unit to enable the steel grabber to continue operating.

2. A method for unmanned steel grabber to grasp strip-shaped scrap steel based on the system described in claim 1, characterized in that: The method includes the following steps: S0: Initiate a data scraping task; S1: Sensor scans strip-shaped scrap steel pile; S2: The process control submodule requests the center of gravity calculation submodule using the scanned sensing data. The center of gravity calculation submodule calculates the center of gravity of the strip scrap steel based on the sensing data and returns it to the process control submodule. S3: The process control submodule uses the center of gravity position as the grab point, calculates the pre-processing placement point, arranges the strip scrap steel according to the center of gravity position, formulates the control process, and outputs it to the control unit. S4: The end effector of the steel grabber grabs a strip of scrap steel at the center of gravity and moves it to the pre-treatment placement point; S5: Repeat S4 to make the strips of scrap steel overlap and their centers of gravity be in a straight line until the weight threshold is reached. The end effector has a weighing sensor to obtain the weight of the gripped material. S6: The end effector grabs all the pre-treated strips of scrap steel, moves the working arm, and raises the end effector in a straight line until all the strips of scrap steel are suspended in the air and reach a certain height; S7: Shake the end effector to obtain the current sensing data of the strip scrap steel through the sensor. The process control submodule uses the sensing data to request the center of gravity detection submodule. The center of gravity detection submodule calculates the offset and returns it to the process control submodule. S8: The process control submodule formulates a control process based on the comparison results of the offset and the threshold: if the threshold is exceeded, it indicates that the gripping is unstable, and the control process is sent to the control unit, the steel grabber lowers its working arm, releases the grabbed strip of scrap steel, and executes S3; if the threshold is within the range, it indicates that the gripping is stable, and the control process is sent to the control unit, so that the steel grabber moves its working arm to continue working.

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