A method for realizing grab closed-loop anti-swing based on laser radar calculation

Abstract

This invention relates to the field of ship unloader technology and discloses a method for achieving closed-loop anti-sway control of the grab bucket based on lidar calculation. The method includes: obtaining point cloud data of the grab bucket using lidar scanning during coal unloading operations; calculating the seven-dimensional parameters of the grab bucket's three-dimensional detection frame corresponding to the point cloud data using a grab bucket spatial positioning algorithm; matching the seven-dimensional parameters with the actual position of the grab bucket in the global coordinate system using spatial coordinate registration technology to calculate the grab bucket's pose in three-dimensional space; calculating the real-time spatial swing angle of the grab bucket using a spatial geometric interpolation algorithm; predicting the instantaneous velocity vector of the grab bucket at the lowest point of its swing trajectory using a dynamic model; generating a reverse velocity command that is opposite in direction and matches the magnitude of the instantaneous velocity vector; and applying the reverse velocity command to the grab bucket to achieve closed-loop anti-sway control. This invention achieves closed-loop anti-sway control of the grab bucket during dynamic ship unloading operations, improving the safety of ship unloading operations.

Description

Technical Field

[0001] This invention relates to the field of ship unloader technology, and specifically to a method for achieving closed-loop anti-swaying of the grab bucket based on lidar calculation. Background Technology

[0002] During the operation of the grab unloader, the grab and the trolley are flexibly connected by a steel wire rope. When the trolley moves, the grab swings back and forth due to inertia. Therefore, anti-sway control of the grab is required.

[0003] In existing technologies, an open-loop anti-sway method is typically used, which periodically increases or decreases the trolley speed to achieve anti-sway. However, this control method cannot adapt to the dynamic changes in the grab bucket's sway and cannot guarantee that the grab bucket's sway is effectively controlled. Summary of the Invention

[0004] This invention provides a method for achieving closed-loop anti-sway of grab bucket based on lidar calculation, in order to solve the problem that the existing technology uses an open-loop anti-sway method, which cannot guarantee that the swing of the grab bucket can be effectively controlled.

[0005] In a first aspect, the present invention provides a method for achieving closed-loop anti-swaying of a grab bucket based on lidar calculations, applicable to a system for achieving closed-loop anti-swaying of a grab bucket based on lidar calculations. The system includes a grab bucket and a trolley, which are flexibly connected by a steel wire rope. The method includes: When the unloader is performing coal unloading operations, the grab bucket is scanned by lidar to obtain point cloud data of the grab bucket; The grab bucket spatial positioning algorithm is called to calculate the seven-dimensional parameters of the grab bucket three-dimensional detection box corresponding to the point cloud data. The seven-dimensional parameters include the spatial center coordinates, columnar dimensions, and rotation angle around the Z-axis. By using spatial coordinate registration technology, the seven-dimensional parameters are matched with the actual position of the grab bucket in the global coordinate system, and the pose of the grab bucket in three-dimensional space is calculated. Based on the pose of the grab bucket in three-dimensional space, combined with the real-time acquired trolley coordinates, the spatial swing angle of the grab bucket relative to the target position of the trolley below is calculated using a spatial geometric interpolation algorithm. The swing period characteristics of the grab are analyzed, and the instantaneous velocity vector of the grab at the lowest point of the swing trajectory is predicted by the dynamic model. Generate a reverse velocity command that is opposite in direction and matches the magnitude of the instantaneous velocity vector velocity, apply the reverse velocity command to the grab bucket, and perform closed-loop anti-sway.

[0006] This invention uses lidar to scan the grab bucket, acquires point cloud data, and calls a grab bucket spatial positioning algorithm to calculate seven-dimensional parameters, providing a data foundation for pose calculation. Spatial coordinate registration technology is used to match the seven-dimensional parameters with the actual position of the grab bucket in the global coordinate system, thus resolving the discrepancy between the lidar detection coordinates and the equipment's operating coordinates. The grab bucket's pose is calculated, its motion characteristics are reconstructed, and the spatial swing angle of the grab bucket relative to the trolley target position is calculated, providing a quantitative basis for swing state analysis. The swing period characteristics are analyzed, and the instantaneous velocity vector is predicted to generate anti-velocity commands. In the dynamic unloading operation, closed-loop anti-sway control of the grab bucket is achieved, improving the safety of the unloading operation.

[0007] In one alternative implementation, the grab spatial positioning algorithm is based on the OpenPCDet open-source framework, uses a lightweight PointPillar backbone network, is jointly optimized with historical unloading data and on-site incremental samples, and is trained end-to-end with the grab as a single target to identify grab discrimination features.

[0008] This invention uses the OpenPCDet open-source framework as the framework for the grab bucket spatial positioning algorithm. It utilizes the mature open-source framework to quickly process point cloud data, selects the lightweight PointPillar backbone network to reduce computing power consumption, integrates historical unloading data and on-site incremental samples for joint optimization to enhance the algorithm's generalization ability, and adopts single-target training to improve anti-interference ability.

[0009] In one optional implementation, the grab spatial positioning algorithm is invoked to calculate the seven-dimensional parameters of the grab's three-dimensional detection box corresponding to the point cloud data, including: The point cloud data is subjected to dual spatiotemporal filtering based on constraints such as the ship's cabin outline, the trolley's safety domain, and the dynamic operation window. The grab spatial positioning algorithm is deployed on edge computing nodes, and the scanning frequency and single forward time are set to generate seven-dimensional parameters of the grab 3D detection box.

[0010] This invention reduces interference from invalid data by performing dual filtering on point cloud data, and deploys the grab bucket spatial positioning algorithm on edge computing nodes to achieve high-speed local computing, adapting to the real-time detection requirements of ship unloaders.

[0011] In one optional implementation, spatial coordinate registration technology is used to match the seven-dimensional parameters with the actual position of the grab in the global coordinate system, thereby calculating the grab's pose in three-dimensional space, including: A global coordinate system for the unloading operation scenario is established with the fixed point of the unloader beam as the origin, the direction along the beam extension as the X-axis, the direction perpendicular to the beam as the Y-axis, and the vertical upward direction as the Z-axis. Spatial coordinate registration technology is used to establish a correspondence between the spatial center coordinates and the physical coordinates in the spatial center coordinates; By combining the column dimensions and the rotation angle around the Z-axis, the position and posture of the grab bucket in real three-dimensional space are restored.

[0012] This invention establishes a global coordinate system, determines a unified detection benchmark, eliminates coordinate deviations, establishes a correspondence between the spatial center coordinates and the physical coordinates within the spatial center coordinates, achieves precise spatial mapping of parameters, restores the pose of the grab bucket in real three-dimensional space, and realizes high-precision calculation of the grab bucket's pose.

[0013] In one optional implementation, by combining the real-time acquired trolley coordinates and using a spatial geometric interpolation algorithm, the spatial swing angle of the grab bucket relative to the target position of the trolley below is calculated, including: Calculate the offset vectors of the actual center coordinates of the grab bucket and the trolley coordinates in three-dimensional space; Using a spatial geometric interpolation algorithm with the offset vector as the interpolation node and combining the physical properties of the wire rope, the offset trajectory of the grab relative to the target position of the trolley is fitted, and the horizontal and vertical swing angle components are calculated. The horizontal and vertical swing angle components together constitute the spatial swing angle.

[0014] This invention calculates the spatial swing angle of the grab bucket using a spatial geometric interpolation algorithm, accurately quantifies the actual swing amplitude of the grab bucket, and reflects the swing state of the grab bucket.

[0015] In one optional implementation, the swing period characteristics of the grab are analyzed, and the instantaneous velocity vector of the grab at the lowest point of the swing trajectory is predicted using a dynamic model, including: Calculate the length of the wire rope used for grab bucket swinging; The length of the wire rope is used as the pendulum length, and the swing period of the grab bucket is calculated based on the pendulum period formula. Calculate the real-time swing speed of the grab bucket; Based on the swing period and swing speed, the instantaneous velocity vector of the grab is predicted when the grab position and the trolley position are synchronized, which is the moment when the grab moves to the lowest point of the swing trajectory.

[0016] This invention utilizes the physical laws of a pendulum to calculate the instantaneous velocity vector of the grab bucket based on the swing period and swing speed, thereby achieving dynamic sensing of the instantaneous velocity vector.

[0017] Secondly, the present invention provides a device for achieving closed-loop anti-swaying of a grab bucket based on lidar calculation, applied to a system for achieving closed-loop anti-swaying of a grab bucket based on lidar calculation. The system includes a grab bucket and a trolley, which are flexibly connected by a steel wire rope. The device includes: The scanning module is used to scan the grab bucket with lidar and obtain point cloud data of the grab bucket when the ship unloader is performing coal unloading operations. The first calculation module is used to call the grab bucket spatial positioning algorithm to calculate the seven-dimensional parameters of the grab bucket three-dimensional detection box corresponding to the point cloud data. The seven-dimensional parameters include the spatial center coordinates, columnar dimensions, and rotation angle around the Z-axis. The matching module is used to match the seven-dimensional parameters with the actual position of the grab bucket in the global coordinate system using spatial coordinate registration technology, and calculate the pose of the grab bucket in three-dimensional space. The second calculation module is used to calculate the spatial swing angle of the grab relative to the target position of the trolley below, based on the pose of the grab bucket in three-dimensional space and the real-time acquired position coordinates of the trolley. The prediction module is used to analyze the swing cycle characteristics of the grab bucket and predict the instantaneous velocity vector of the grab bucket at the lowest point of the swing trajectory through a dynamic model. The anti-sway module is used to generate a reverse speed command that is opposite in direction and matches the magnitude of the instantaneous velocity vector speed, and apply the reverse speed command to the grab bucket to perform closed-loop anti-sway.

[0018] Thirdly, the present invention provides an electronic device, comprising: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to perform the method for achieving closed-loop anti-swaying of the grab bucket based on lidar calculation as described in the first aspect or any corresponding embodiment.

[0019] Fourthly, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to execute the method for implementing closed-loop anti-sway of a grab bucket based on lidar calculation, as described in the first aspect above or any corresponding embodiment.

[0020] Fifthly, the present invention provides a computer program product, including computer instructions, which are used to cause a computer to execute the method for implementing closed-loop anti-sway of a grab bucket based on lidar calculation in the first aspect or any corresponding embodiment described above. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a flowchart illustrating a method for implementing closed-loop anti-swaying of a grab bucket based on lidar calculation according to an embodiment of the present invention. Figure 2This is an overall schematic diagram of a grab bucket closed-loop anti-sway system based on lidar calculation according to an embodiment of the present invention; Figure 3 This is a structural block diagram of a device for implementing closed-loop anti-swaying of a grab bucket based on lidar calculation according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the hardware structure of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] It is understood that before using the technical solutions disclosed in the various embodiments of the present invention, users should be informed of the types, scope of use, and usage scenarios of the personal information involved in the present invention and their authorization should be obtained in accordance with relevant laws and regulations through appropriate means.

[0025] In related technologies, during the fully automated operation of ship unloaders, the traditional open-loop anti-sway method is still commonly used to control the grab bucket's sway, achieving anti-sway by periodically increasing or decreasing the trolley speed. However, this control method cannot ensure that every swing of the grab bucket is effectively controlled. Once the grab bucket swings too much, timely intervention by personnel is required; otherwise, it may cause damage to the ship and the ship unloader.

[0026] According to an embodiment of the present invention, a method embodiment for implementing closed-loop anti-sway of a grab bucket based on lidar calculation is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0027] This embodiment provides a method for achieving closed-loop anti-sway of the grab bucket based on lidar calculation. Figure 1 This is a flowchart of a method for implementing closed-loop anti-swaying of a grab bucket based on lidar calculation according to an embodiment of the present invention, as shown below. Figure 1 As shown, the process includes the following steps: Step S101: When the unloader is performing coal unloading operations, the grab bucket is scanned using lidar to obtain point cloud data of the grab bucket.

[0028] In embodiments of the present invention, such as Figure 2As shown, a three-dimensional lidar is installed at the head of the beam. When the unloader is performing coal unloading operations, the lidar is used to continuously scan the grab bucket in real time to obtain dynamically changing, high-precision point cloud data.

[0029] Understandably, a three-dimensional digital model of the grab is constructed based on the acquired point cloud data in order to accurately reproduce the overall spatial shape and other features of the grab.

[0030] Step S102: Call the grab bucket spatial positioning algorithm to calculate the seven-dimensional parameters of the grab bucket three-dimensional detection box corresponding to the point cloud data.

[0031] In this embodiment of the invention, a grab bucket spatial positioning algorithm is invoked. Point cloud data is input into the grab bucket spatial positioning algorithm deployed on an edge computing node for real-time inference. After inference calculation, seven-dimensional parameters of a three-dimensional detection box characterizing the spatial state of the grab bucket are output. These seven-dimensional parameters include the spatial center coordinates (x, y, z), cylindrical dimensions (l, w, h), and rotation angle around the Z-axis. .

[0032] Step S103: Use spatial coordinate registration technology to match the seven-dimensional parameters with the actual position of the grab bucket in the global coordinate system, and calculate the pose of the grab bucket in three-dimensional space.

[0033] In this embodiment of the invention, the seven-dimensional parameters of the calculated three-dimensional detection frame of the grab bucket are precisely matched with the actual position of the grab bucket in the global coordinate system by using spatial coordinate registration technology, thereby calculating the precise pose of the grab bucket in three-dimensional space, which includes position and attitude.

[0034] Step S104: Based on the pose of the grab bucket in three-dimensional space and combined with the real-time acquired trolley coordinates, the spatial swing angle of the grab bucket relative to the target position of the trolley below is calculated using a spatial geometric interpolation algorithm.

[0035] In this embodiment of the invention, an encoder is installed on the trolley's traveling mechanism to accurately measure the trolley's real-time position information. Based on the calculated pose of the grab bucket in three-dimensional space, combined with the real-time acquired trolley position coordinates, a spatial geometric interpolation algorithm is used to calculate the spatial swing angle of the grab bucket relative to the target position of the trolley below.

[0036] Step S105: Analyze the swing period characteristics of the grab bucket and predict the instantaneous velocity vector of the grab bucket at the lowest point of the swing trajectory using a dynamic model.

[0037] In this embodiment of the invention, after obtaining the swing angle of the grab bucket, the swing period characteristics of the grab bucket are further analyzed by the position change of the wire rope. Based on the swing period characteristics, the instantaneous velocity vector of the grab bucket at the lowest point of the swing trajectory is accurately predicted by calculating through a dynamic model.

[0038] Step S106: Generate a reverse speed command that is opposite in direction and matches the magnitude of the instantaneous velocity vector velocity, and apply the reverse speed command to the grab bucket to perform closed-loop anti-swaying.

[0039] In this embodiment of the invention, the core of anti-sway control lies in applying a reverse speed command to the grab bucket at the appropriate time, which is opposite in direction and matches the magnitude of the speed at the predicted lowest point. This forms an efficient and autonomous real-time closed-loop control that can continuously sense the grab bucket's state and apply the optimal control quantity in real time. Thus, in the dynamic unloading operation, the grab bucket can achieve precise and stable anti-sway control. This active intervention can effectively counteract the swaying energy and achieve rapid sway reduction and stabilization of the grab bucket.

[0040] This embodiment provides a method for achieving closed-loop anti-sway control of the grab bucket based on LiDAR calculation. It uses LiDAR to scan the grab bucket, acquires point cloud data, and calls a grab bucket spatial positioning algorithm to calculate seven-dimensional parameters, providing a data foundation for pose calculation. Spatial coordinate registration technology is used to match the seven-dimensional parameters with the actual position of the grab bucket in the global coordinate system, thus resolving the deviation between the LiDAR detection coordinates and the equipment's operating coordinates. The grab bucket's pose is calculated, its motion characteristics are restored, and the spatial swing angle of the grab bucket relative to the trolley target position is calculated, providing a quantitative basis for swing state analysis. The swing period characteristics are analyzed, and the instantaneous velocity vector is predicted to generate an anti-velocity command. In the dynamic unloading operation, closed-loop anti-sway control of the grab bucket is achieved, improving the safety of the unloading operation.

[0041] This embodiment provides a method for achieving closed-loop anti-sway of the grab bucket based on lidar calculation. The process includes the following steps: Step S201: When the unloader is performing coal unloading operations, the grab bucket is scanned using lidar to obtain point cloud data of the grab bucket.

[0042] Please see details Figure 1 Step S101 of the illustrated embodiment will not be described again here.

[0043] Step S202: Call the grab bucket spatial positioning algorithm to calculate the seven-dimensional parameters of the grab bucket three-dimensional detection box corresponding to the point cloud data.

[0044] Specifically, the grab spatial positioning algorithm is based on the OpenPCDet open-source framework, uses a lightweight PointPillar backbone network, is jointly optimized with historical unloading data and on-site incremental samples, and is trained end-to-end with the grab as a single target to identify the grab's discrimination features.

[0045] In this embodiment of the invention, the grab bucket spatial positioning algorithm is based on the OpenPCDet open source framework, adopts a lightweight PointPillar backbone network, and is jointly optimized with large-scale historical unloading data and on-site incremental samples. It conducts end-to-end training only for the single target of the grab bucket, and fully learns the high discriminative features of the grab bucket under extreme working conditions such as coal dust, backlight, shaking, and partial obstruction.

[0046] By using the OpenPCDet open-source framework as the framework for the grab bucket spatial positioning algorithm, the mature open-source framework is used to quickly process point cloud data. The lightweight PointPillar backbone network is selected to reduce computing power consumption. Historical unloading data and on-site incremental samples are combined for joint optimization to enhance the algorithm's generalization ability. Single-target training is adopted to improve anti-interference ability.

[0047] Specifically, step S202 includes: Step S2021: Using the cabin outline, the trolley safety domain, and the dynamic operation window as constraints, perform spatiotemporal dual filtering on the point cloud data; Step S2022: Deploy the grab spatial positioning algorithm on the edge computing node, set the scanning frequency and single forward time, and generate the seven-dimensional parameters of the grab 3D detection box.

[0048] In this embodiment of the invention, before the grab spatial positioning algorithm model inference, the original point cloud data is subjected to spatiotemporal dual filtering based on the ship's cabin outline, the trolley's safety domain, and the dynamic operating window to remove redundant background and motion clutter, ensuring that the input data is strongly correlated with the grab. During the grab spatial positioning algorithm model inference stage, the algorithm is deployed on edge computing nodes, with a scanning frequency set to greater than 25Hz and a single forward inference time set to less than 30ms. On the edge computing nodes, the grab spatial positioning algorithm runs in real-time at a frequency greater than 25Hz, with a single forward inference time consistently below 30ms. After the grab spatial positioning algorithm model completes inference, it outputs the seven-dimensional parameters of the grab within the three-dimensional detection frame.

[0049] By performing dual filtering on point cloud data to reduce interference from invalid data, the grab bucket spatial positioning algorithm is deployed on edge computing nodes to achieve high-speed local computation, adapting to the real-time detection requirements of ship unloaders.

[0050] Step S203: Use spatial coordinate registration technology to match the seven-dimensional parameters with the actual position of the grab bucket in the global coordinate system, and calculate the pose of the grab bucket in three-dimensional space.

[0051] Specifically, step S203 includes: Step S2031: Establish a global coordinate system for the unloading operation scenario with the fixed point of the unloading machine beam as the origin, the X-axis as the direction along the beam extension, the Y-axis as the direction perpendicular to the beam, and the Z-axis as the vertical upward direction. Step S2032: Use spatial coordinate registration technology to establish a correspondence between the spatial center coordinates and the physical coordinates in the spatial center coordinates; Step S2033: Combine the column dimensions and the rotation angle around the Z-axis to restore the pose of the grab bucket in real three-dimensional space.

[0052] In this embodiment of the invention, the core of spatial coordinate registration is to establish a mapping relationship between the spatial center coordinates in the seven-dimensional parameters and the physical spatial coordinates of the grab bucket in the global coordinate system, so as to lay a coordinate reference for pose restoration.

[0053] First, a global coordinate system for the unloading operation scenario is established with the fixed point of the unloading machine beam as the origin, the direction along the beam extension as the X-axis, the direction perpendicular to the beam as the Y-axis, and the vertical upward direction as the Z-axis, thus clarifying a unified spatial reference benchmark.

[0054] Then, through spatial coordinate registration technology, a precise one-to-one correspondence is established between the spatial center coordinates and the physical space of the unloading operation in the global coordinate system.

[0055] Finally, using the spatial center coordinates as the geometric center and the columnar dimensions as the parameters of the 3D detection frame, a 3D detection frame for the grab is constructed in the global coordinate system, restoring the grab's spatial positioning in the real 3D space. Using the Z-axis as the rotation reference and a rotation angle around the Z-axis, the 3D detection frame is rotated and matched to restore the grab's oscillation in the real 3D space, thus completing the restoration of the grab's pose in the real 3D space in the global coordinate system.

[0056] By establishing a global coordinate system, determining a unified detection benchmark, eliminating coordinate deviations, and establishing a correspondence between the spatial center coordinates and the physical coordinates within the spatial center coordinates, precise spatial mapping of parameters is achieved, restoring the grab's pose in real three-dimensional space, and realizing high-precision calculation of the grab's pose.

[0057] Step S204: Based on the pose of the grab bucket in three-dimensional space and combined with the real-time acquired position coordinates of the trolley, the real-time spatial swing angle of the grab bucket relative to the target position of the trolley below is calculated using a spatial geometric interpolation algorithm.

[0058] Specifically, step S204 includes: Step S2041: Calculate the offset vectors of the actual center coordinates of the grab bucket and the target coordinates of the trolley in three-dimensional space; Step S2042: Using a spatial geometric interpolation algorithm, with the offset vector as the interpolation node, and combined with the physical properties of the wire rope, the offset trajectory of the grab relative to the target coordinates of the trolley is fitted, and the horizontal and vertical swing angle components are calculated. Step S2043: Combine the horizontal swing angle component and the vertical swing angle component to form the spatial swing angle.

[0059] In this embodiment of the invention, taking the actual center coordinates of the grab bucket as (x1, y1, z1) and the target coordinates of the trolley as (x2, y2, z2) as an example, the offset vector between the actual center coordinates of the grab bucket and the target coordinates of the trolley in three-dimensional space is calculated as follows: ,in, This is the offset along the x-axis. This is the offset along the y-axis. This represents the offset along the z-axis.

[0060] Because lidar scanning contains slight noise and the grab's swing is a continuous trajectory, a spatial geometric interpolation algorithm is used to smooth and filter the continuously sampled offset vectors, remove discrete noise, and fit the continuous vector trajectory of the grab's offset.

[0061] The grab bucket and the trolley are flexibly connected by a steel wire rope. Its swing follows the physical characteristics of a pendulum. The steel wire rope is the pendulum rope, and the grab bucket is the pendulum. The difference between the vertical height of the trolley's lifting drum and the actual vertical height of the grab bucket is the effective length of the steel wire rope. The effective length of the steel wire rope is the pendulum length of the grab bucket's pendulum motion. The target coordinates of the trolley are the center of the swing angle circle, and the effective length of the steel wire rope is the radius of the arc. The spatial offset trajectory of the grab bucket is an arc curve in three-dimensional space. Using a spatial geometric interpolation algorithm, with continuously sampled offset vectors as interpolation nodes, the offset trajectory of the grab bucket relative to the target coordinates of the trolley in three-dimensional space is fitted.

[0062] Project the offset vector onto a horizontal plane and calculate the horizontal offset. Using the target coordinates of the trolley as the center, the length of the wire rope as the hypotenuse, and the horizontal offset as the opposite side, calculate the horizontal swing angle component using the arcsine trigonometric function. Using the length of the wire rope as the hypotenuse and the vertical offset as the opposite side, calculate the numerical swing angle component using the arcsine trigonometric function again. Combine the horizontal and vertical swing angle components in three-dimensional space to obtain the spatial swing angle.

[0063] The spatial swing angle of the grab is calculated by using a spatial geometric interpolation algorithm, which accurately quantifies the actual swing amplitude of the grab and reflects the swing state of the grab.

[0064] Step S205: Analyze the swing period characteristics of the grab bucket and predict the instantaneous velocity vector of the grab bucket at the lowest point of the swing trajectory through dynamic model calculation.

[0065] Specifically, step S205 includes: Step S2051: Calculate the length of the wire rope for the grab bucket to swing. Step S2052: Using the length of the wire rope as the pendulum length, calculate the swing period of the grab bucket based on the pendulum period formula; Step S2053: Calculate the real-time swing speed of the grab bucket; Step S2054: Based on the swing period and swing speed, the instantaneous velocity vector of the grab is predicted when the grab position and the trolley position are synchronized, taking the moment when the grab moves to the lowest point of the swing trajectory.

[0066] In this embodiment of the invention, the effective length of the wire rope is defined as the difference between the vertical height of the hoisting drum of the trolley and the actual vertical height of the grab bucket, and the effective length of the wire rope is defined as the pendulum length of the grab bucket's pendulum motion.

[0067] Calculate the grab's swing period based on the core formula for the simple pendulum period:

[0068] in, T For the oscillation period, L Let g be the pendulum length and g be the acceleration due to gravity.

[0069] The real-time swing speed of the grab is approximated by the grab's position change rate between adjacent frames, based on the grab's position scanned by the lidar.

[0070] When the position of the grab bucket and the position of the trolley are synchronized, it is the moment when the grab bucket moves to the lowest point of the swing trajectory. The instantaneous velocity vector at that moment is synthesized by the instantaneous velocity components of the grab bucket on the X-axis, Y-axis and Z-axis of the global coordinate system.

[0071] Step S206: Generate a reverse speed command that is opposite in direction and matches the magnitude of the instantaneous velocity vector velocity, and apply the reverse speed command to the grab bucket to perform closed-loop anti-swaying.

[0072] Please see details Figure 1 Step S106 of the illustrated embodiment will not be described again here.

[0073] The method for achieving closed-loop anti-swaying of the grab bucket based on lidar calculation provided in this embodiment calculates the instantaneous velocity vector of the grab bucket based on the swing period and swing speed according to the physical law of pendulum, so as to achieve dynamic perception of the instantaneous velocity vector.

[0074] This embodiment also provides a device for implementing closed-loop anti-sway of the grab bucket based on lidar calculation. This device is used to implement the above embodiments and preferred embodiments, and details already described will not be repeated. As used below, the term "module" can be a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0075] This embodiment provides a device for achieving closed-loop anti-swaying of a grab bucket based on lidar calculations. It is applied to a system for achieving closed-loop anti-swaying of a grab bucket based on lidar calculations. This system includes a grab bucket and a trolley, which are flexibly connected by a steel wire rope. Figure 3 As shown, it includes: The scanning module 301 is used to scan the grab bucket with lidar and obtain the point cloud data of the grab bucket when the unloader is performing coal unloading operations. The first calculation module 302 is used to call the grab bucket spatial positioning algorithm to calculate the seven-dimensional parameters of the grab bucket three-dimensional detection box corresponding to the point cloud data. The seven-dimensional parameters include the spatial center coordinates, columnar dimensions, and rotation angle around the Z-axis. The matching module 303 is used to match the seven-dimensional parameters with the actual position of the grab bucket in the global coordinate system using spatial coordinate registration technology, and calculate the pose of the grab bucket in three-dimensional space. The second calculation module 304 is used to calculate the spatial swing angle of the grab relative to the target position of the trolley below, based on the pose of the grab bucket in three-dimensional space and the real-time acquired position coordinates of the trolley. The prediction module 305 is used to analyze the swing period characteristics of the grab bucket and predict the instantaneous velocity vector of the grab bucket at the lowest point of the swing trajectory through a dynamic model. The anti-sway module 306 is used to generate a reverse speed command that is opposite in direction and matches the magnitude of the instantaneous velocity vector velocity, and apply the reverse speed command to the grab bucket to perform closed-loop anti-sway.

[0076] In some alternative implementations, the first computing module 302 includes: The filtering unit is used to perform spatiotemporal dual filtering on point cloud data, constrained by the ship's cabin outline, the trolley's safety domain, and the dynamic operation window. The parameter generation unit is used to deploy the grab bucket spatial positioning algorithm on the edge computing node, set the scanning frequency and single forward time, and generate seven-dimensional parameters of the grab bucket three-dimensional detection box.

[0077] In some alternative implementations, the matching module 303 includes: The coordinate system establishment unit is used to establish a global coordinate system for the unloading operation scenario, with the fixed point of the unloading machine beam as the origin, the X-axis along the beam extension direction as the X-axis, the direction perpendicular to the beam as the Y-axis, and the vertical upward direction as the Z-axis. The correspondence establishment unit is used to establish a correspondence between the spatial center coordinates and the physical coordinates in the spatial center coordinates using spatial coordinate registration technology. The pose restoration unit is used to restore the pose of the grab bucket in real three-dimensional space by combining the columnar dimensions and the rotation angle around the Z-axis.

[0078] In some alternative implementations, the second computing module 304 includes: The first calculation unit is used to calculate the offset vectors of the actual center coordinates of the grab bucket and the trolley coordinates in three-dimensional space; The fitting unit is used to fit the offset trajectory of the grab relative to the target position of the trolley using a spatial geometric interpolation algorithm, with the offset vector as the interpolation node, combined with the physical properties of the wire rope, and to calculate the horizontal and vertical swing angle components. The swing angle component unit is used to combine the horizontal and vertical swing angle components to form a spatial swing angle.

[0079] In some alternative implementations, the prediction module 305 includes: The second calculation unit is used to calculate the length of the wire rope for the grab bucket's swing. The third calculation unit is used to calculate the swing period of the grab bucket based on the pendulum period formula, using the length of the wire rope as the pendulum length. The fourth calculation unit is used to calculate the real-time swing speed of the grab bucket; The prediction unit is used to predict the instantaneous velocity vector of the grab bucket based on the swing period and swing speed, with the moment when the grab bucket position and the trolley position are synchronized as the moment when the grab bucket moves to the lowest point of the swing trajectory.

[0080] The device for achieving closed-loop anti-swaying of the grab bucket based on lidar calculation provided in this embodiment of the invention can execute the method for achieving closed-loop anti-swaying of the grab bucket based on lidar calculation provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method. Further functional descriptions of the above modules and units are the same as in the corresponding embodiments described above, and will not be repeated here.

[0081] Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention.

[0082] The following is a detailed reference. Figure 4 This diagram illustrates a structural schematic suitable for implementing an electronic device according to embodiments of the present invention. The electronic device may include a processor (e.g., a central processing unit, graphics processor, etc.) 401, which can perform various appropriate actions and processes according to a program stored in read-only memory (ROM) 402 or a program loaded from memory 408 into random access memory (RAM) 403. The RAM 403 also stores various programs and data required for the operation of the electronic device. The processor 401, ROM 402, and RAM 403 are interconnected via a bus 404. An input / output (I / O) interface 405 is also connected to the bus 404.

[0083] Typically, the following devices can be connected to I / O interface 405: input devices 406 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 407 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; memory devices 408 including, for example, magnetic tapes, hard disks, etc.; and communication devices 409. Communication device 409 allows electronic devices to communicate wirelessly or wiredly with other devices to exchange data. Although Figure 4 Electronic devices with various devices are shown, but it should be understood that it is not required to implement or have all of the devices shown, and more or fewer devices may be implemented or have instead.

[0084] In particular, according to embodiments of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product comprising a computer program carried on a non-transitory computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device 409, or installed from a memory 408, or installed from a ROM 402. When the computer program is executed by the processor 401, it performs the functions defined in the method for implementing closed-loop anti-swaying of a grab bucket based on lidar calculations according to embodiments of the present invention.

[0085] Figure 4 The electronic device shown is merely an example and should not be construed as limiting the functionality and scope of use of the embodiments of the present invention.

[0086] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code. When the software or computer code is accessed and executed by the computer, processor, or hardware, the method for implementing closed-loop anti-sway of the grab bucket based on lidar calculation shown in the above embodiments is implemented.

[0087] A portion of this invention can be applied as a computer program product, such as computer program instructions, which, when executed by a computer, can invoke or provide the methods and / or technical solutions according to the invention through the operation of the computer. Those skilled in the art will understand that the forms in which computer program instructions exist in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include, but are not limited to: the computer directly executing the instructions, or the computer compiling the instructions and then executing the corresponding compiled program, or the computer reading and executing the instructions, or the computer reading and installing the instructions and then executing the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible to a computer.

[0088] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and all such modifications and variations fall within the scope defined by the appended invention.

Claims

1. A method for achieving closed-loop anti-swaying of a grab bucket based on lidar calculation, characterized in that, An application is made to a system for achieving closed-loop anti-swaying of a grab bucket based on lidar calculations. The system includes a grab bucket and a trolley, which are flexibly connected by a steel wire rope. The method includes: When the unloader is performing coal unloading operations, the grab bucket is scanned by lidar to obtain point cloud data of the grab bucket; The grab bucket spatial positioning algorithm is called to calculate the seven-dimensional parameters of the grab bucket three-dimensional detection box corresponding to the point cloud data. The seven-dimensional parameters include the spatial center coordinates, columnar dimensions, and rotation angle around the Z-axis. The seven-dimensional parameters are matched with the actual position of the grab bucket in the global coordinate system using spatial coordinate registration technology, and the pose of the grab bucket in three-dimensional space is calculated. Based on the pose of the grab bucket in three-dimensional space, combined with the real-time acquired trolley coordinates, the spatial swing angle of the grab bucket relative to the target position of the trolley below is calculated using a spatial geometric interpolation algorithm. The swing period characteristics of the grab are analyzed, and the instantaneous velocity vector of the grab at the lowest point of the swing trajectory is predicted by the dynamic model. A reverse velocity command is generated that is opposite in direction and matches the magnitude of the instantaneous velocity vector. The reverse velocity command is then applied to the grab bucket to perform closed-loop anti-swaying.

2. The method according to claim 1, characterized in that, The grab spatial positioning algorithm is based on the OpenPCDet open-source framework, uses a lightweight PointPillar backbone network, is jointly optimized with historical unloading data and on-site incremental samples, and is trained end-to-end with the grab as a single target to identify grab discrimination features.

3. The method according to claim 1, characterized in that, The step of calling the grab spatial positioning algorithm to calculate the seven-dimensional parameters of the grab 3D detection box corresponding to the point cloud data includes: The point cloud data is subjected to spatiotemporal dual filtering based on the ship's cabin outline, the trolley's safety domain, and the dynamic operation window. The grab spatial positioning algorithm is deployed on edge computing nodes, and the scanning frequency and single forward time are set to generate seven-dimensional parameters of the grab 3D detection box.

4. The method according to claim 3, characterized in that, The process of matching the seven-dimensional parameters with the actual position of the grab in the global coordinate system using spatial coordinate registration technology to calculate the grab's pose in three-dimensional space includes: A global coordinate system for the unloading operation scenario is established with the fixed point of the unloader beam as the origin, the direction along the beam extension as the X-axis, the direction perpendicular to the beam as the Y-axis, and the vertical upward direction as the Z-axis. A spatial coordinate registration technique is used to establish a correspondence between the spatial center coordinates and the physical coordinates within the spatial center coordinates. By combining the columnar dimensions and the rotation angle around the Z-axis, the position and posture of the grab bucket in real three-dimensional space are restored.

5. The method according to claim 1, characterized in that, The method of combining the real-time acquired trolley coordinates and using a spatial geometric interpolation algorithm to calculate the spatial swing angle of the grab bucket relative to the target position of the trolley below includes: Calculate the offset vectors of the actual center coordinates of the grab bucket and the trolley coordinates in three-dimensional space; Using a spatial geometric interpolation algorithm, with the offset vector as the interpolation node, and combined with the physical properties of the wire rope, the offset trajectory of the grab relative to the target position of the trolley is fitted, and the horizontal and vertical swing angle components are calculated. The horizontal swing angle component and the vertical swing angle component together constitute the spatial swing angle.

6. The method according to claim 1, characterized in that, The analysis of the grab's swing period characteristics, using a dynamic model to predict the grab's instantaneous velocity vector at the lowest point of its swing trajectory, includes: Calculate the length of the wire rope used for grab bucket swinging; The length of the steel wire rope is used as the pendulum length, and the swing period of the grab bucket is calculated based on the pendulum period formula. Calculate the real-time swing speed of the grab bucket; Based on the swing period and the swing speed, the instantaneous velocity vector of the grab is predicted when the grab position and the trolley position are synchronized, with the grab moving to the lowest point of the swing trajectory.

7. A device for achieving closed-loop anti-swaying of a grab bucket based on lidar calculation, characterized in that, An application to a system for achieving closed-loop anti-sway of a grab bucket based on lidar calculations, the system comprising a grab bucket and a trolley, the grab bucket and the trolley being flexibly connected by a steel wire rope, the device comprising: The scanning module is used to scan the grab bucket with lidar and obtain point cloud data of the grab bucket when the ship unloader is performing coal unloading operations. The first calculation module is used to call the grab bucket spatial positioning algorithm to calculate the seven-dimensional parameters of the grab bucket three-dimensional detection box corresponding to the point cloud data. The seven-dimensional parameters include the spatial center coordinates, columnar dimensions, and rotation angle around the Z-axis. The matching module is used to match the seven-dimensional parameters with the actual position of the grab bucket in the global coordinate system using spatial coordinate registration technology, and calculate the pose of the grab bucket in three-dimensional space. The second calculation module is used to calculate the spatial swing angle of the grab relative to the target position of the trolley below, based on the pose of the grab bucket in three-dimensional space and the real-time acquired trolley coordinates, using a spatial geometric interpolation algorithm. The prediction module is used to analyze the swing cycle characteristics of the grab bucket and predict the instantaneous velocity vector of the grab bucket at the lowest point of the swing trajectory through a dynamic model. The anti-sway module is used to generate a reverse speed command that is opposite in direction and matches the magnitude of the instantaneous velocity vector, and apply the reverse speed command to the grab bucket to perform closed-loop anti-sway.

8. An electronic device, characterized in that, include: The system includes a memory and a processor, which are interconnected. The memory stores computer instructions, and the processor executes the computer instructions to perform the method for achieving closed-loop anti-swaying of the grab bucket based on lidar calculation, as described in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to execute the method for achieving closed-loop anti-sway of the grab bucket based on lidar calculation as described in any one of claims 1 to 6.

10. A computer program product, characterized in that, The method includes computer instructions for causing a computer to execute the method for achieving closed-loop anti-swaying of a grab bucket based on lidar calculations as described in any one of claims 1 to 6.

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