Anti-hoisting detection method, device and system based on single-line laser radar

Abstract

The invention relates to the technical field of lifting prevention, and particularly discloses a lifting prevention detection method, device and system based on a single-line laser radar, and the method comprises the steps: obtaining the laser point cloud data information of the single-line laser radar; preprocessing the laser point cloud data information to obtain a target point cloud area with container scanning line information; according to the container truck scanning point cloud search result in the target point cloud area, whether the container is separated from the container truck or not is judged; when it is determined that the container and the container truck are not separated, whether the container truck is lifted or not is determined according to the lifting height of the container scanning line; when it is determined that the container is separated from the container truck, whether the container truck is lifted or not is determined according to the lifting height of the container truck; when it is determined that the container truck is hoisted, an alarm signal is generated and sent. According to the anti-hoisting detection method based on the single-line laser radar, anti-hoisting detection can be efficiently and reliably carried out so as to reduce the accident rate.

Description

Technical Field

[0001] The present invention relates to the field of anti-lifting technology, and in particular to an anti-lifting detection method based on a single-line laser radar, an anti-lifting detection device based on a single-line laser radar, and an anti-lifting detection system based on a single-line laser radar. Background Art

[0002] Gantry cranes are the primary container handling equipment at port yards. While they improve loading and unloading efficiency, they also present significant safety risks. With existing technology, cranes can easily lift containers and pallets during unloading due to incomplete latching of pallets, resulting in equipment damage and even casualties, posing a serious safety hazard.

[0003] Therefore, how to efficiently and reliably perform anti-lifting detection to reduce the accident rate has become a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0004] The present invention provides an anti-lifting detection method based on a single-line laser radar, an anti-lifting detection device based on a single-line laser radar, and an anti-lifting detection system based on a single-line laser radar, which solve the problem in related technologies that anti-lifting detection cannot be performed efficiently and reliably.

[0005] As a first aspect of the present invention, a single-line laser radar-based anti-lifting detection method is provided, which includes:

[0006] Obtain laser point cloud data information of single-line laser radar;

[0007] Preprocessing the laser point cloud data information to obtain a target point cloud area with container scanning line information;

[0008] Determine whether the container and the truck are separated based on the search results of the truck scanning point cloud within the target point cloud area;

[0009] When it is determined that the container and the container truck are not separated, determining whether the container truck is lifted according to the lifting height of the container scanning line;

[0010] When it is determined that the container is separated from the container truck, whether the container truck is lifted is determined based on the lifting height of the container truck;

[0011] When it is determined that the container truck is lifted, an alarm signal is generated and sent.

[0012] Furthermore, determining whether the container and the container truck are separated based on the search results of the container truck scanning point cloud within the target point cloud area includes:

[0013] Determine whether there is a container truck scanning point cloud within the target point cloud area;

[0014] If there is a container truck scanning point cloud, it is determined that the container is separated from the container truck;

[0015] If there is no container truck scanning point cloud, it is determined that the container and the container truck are not separated.

[0016] Furthermore, when it is determined that the container and the container truck are not separated, determining whether the container truck is lifted according to the lifting height of the container scanning line includes:

[0017] When it is determined that the container and the container truck are not separated, calculating the lifting height of the lower edge endpoint of the container scanning line;

[0018] If the lifting height of the lower edge endpoint of the container scanning line is greater than a preset safety threshold, it is determined that the container truck is lifted;

[0019] If the lifting height of the lower edge endpoint of the container scanning line is not greater than a preset safety threshold, it is determined that the container truck is not lifted.

[0020] Furthermore, when it is determined that the container is separated from the container truck, determining whether the container truck is lifted according to the lifting height of the container truck includes:

[0021] When it is determined that the container is separated from the truck, whether the current truck's lifting height is normal is determined based on the truck's top lifting height and the difference between the top lifting heights of two adjacent trucks.

[0022] If the lifting height of the current container truck is abnormal, the lifting height of the current container truck is corrected and the corrected normal lifting height is obtained;

[0023] If the current lifting height of the container truck is the normal lifting height, calculate the horizontal deviation rate of the current container truck;

[0024] Whether the current container truck is lifted is determined based on the normal lifting height of the current container truck and the horizontal deviation rate of the current container truck.

[0025] Furthermore, determining whether the current container truck is lifted according to the normal lifting height of the current container truck and the horizontal deviation rate of the current container truck includes:

[0026] Comparing the normal lifting height of the current container truck with a preset safety threshold, and comparing the horizontal deviation rate of the current container truck with a preset deviation rate threshold;

[0027] If the normal lifting height of the current container truck is greater than a preset safety threshold, or the horizontal deviation rate of the current container truck is greater than a preset deviation rate threshold, it is determined that the container truck is lifted;

[0028] If the normal lifting height of the current container truck is not greater than the preset safety threshold, and the horizontal deviation rate of the current container truck is not greater than the preset deviation rate threshold, it is determined that the container truck is not lifted.

[0029] Furthermore, the horizontal deviation rate of the current container truck is calculated, including:

[0030] Construct a standardized reference point set for the card point cloud;

[0031] Obtain real-time point cloud of the container truck during the lifting process;

[0032] Matching each point in the container truck real-time point cloud according to the standardized reference point set and matching each point in the container truck real-time point cloud with the standardized point set to obtain a valid matching result and an offset matching result for bidirectional matching;

[0033] A dynamic offset evaluation is performed based on the offset matching result and the effective matching result to obtain the horizontal offset rate of the current container truck.

[0034] Furthermore, the lifting height of the current container truck is corrected, including:

[0035] Calculate the top height of the previous frame and the top height of the current frame of the container truck, and calculate the bottom height of the previous frame and the bottom height of the current frame of the container;

[0036] Determine whether the point cloud of the container truck is separated from the container based on the top height difference between the top height of the current frame of the container truck and the top height of the previous frame, and the difference between the top height difference and the bottom height difference of the container;

[0037] If it is determined that part of the point cloud of the container truck is separated from the container, the reference height of the container truck and the top height of the previous frame of the container truck are reset to the top height of the current frame of the container truck, and the lifting height of the top of the container truck is reset to 0;

[0038] Record the top height of the truck and the bottom height of the container in the current frame.

[0039] Furthermore, the laser point cloud data information is preprocessed, including:

[0040] performing clustering processing on the laser point cloud data information to obtain a plurality of laser point cloud clusters;

[0041] Linear fitting is performed on each laser point cloud cluster to obtain the target point cloud area with container scanning line information;

[0042] Searching in the target point cloud area with the container scanning information based on the prior knowledge of the container's geometric features to obtain the container scanning line;

[0043] Determine a container truck search area according to the container scanning line;

[0044] The container truck scanning point cloud is searched in the container truck search area to obtain the container truck scanning point cloud search result.

[0045] As another aspect of the present invention, a single-line laser radar-based anti-lifting detection device is provided, which is used to implement the above-mentioned single-line laser radar-based anti-lifting detection method, including:

[0046] Acquisition module, used to obtain laser point cloud data information of single-line laser radar;

[0047] A preprocessing module, configured to preprocess the laser point cloud data information to obtain a target point cloud area with container scanning line information;

[0048] A determination module, configured to determine whether the container and the container truck are separated based on the search results of the container truck scanning point cloud within the target point cloud area;

[0049] a non-separation determination module, configured to determine whether the container truck is lifted based on the lifting height of the container scanning line when it is determined that the container and the container truck are not separated;

[0050] A separation determination module is used to determine whether the container truck is lifted according to the lifting height of the container truck when it is determined that the container is separated from the container truck;

[0051] The alarm module is used to generate and send an alarm signal when it is determined that the container truck is lifted.

[0052] As another aspect of the present invention, an anti-lifting detection system based on a single-line laser radar is provided, which includes: a controller and the anti-lifting detection device based on the single-line laser radar as described above, the controller is communicatively connected with the anti-lifting detection device based on the single-line laser radar, and the anti-lifting detection device based on the single-line laser radar can generate an alarm signal when it is determined that the container truck is lifted and send the alarm signal to the controller.

[0053] The anti-lifting detection method based on a single-line laser radar provided by the present invention obtains point cloud information of the container and the container truck in real time through the single-line laser radar, analyzes the separation status of the container and the container truck pallet, and triggers an alarm signal when it is determined that the container truck is lifted. This avoids the accident of the crane accidentally lifting the container and the container truck pallet together when unloading the container, improves the safety and efficiency during operation, and the anti-lifting detection method based on the single-line laser radar can realize anti-lifting detection efficiently and reliably. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention, but do not constitute a limitation of the present invention.

[0055] Figure 1 This is a flow chart of the anti-lifting detection method based on single-line laser radar provided by the present invention.

[0056] Figure 2 This is a flowchart of preprocessing laser point cloud data information provided by the present invention.

[0057] Figure 3 This is a schematic diagram of the single-line laser radar scanning point cloud provided by the present invention.

[0058] Figure 4 This is a flow chart for determining whether a container and a container truck are separated, provided by the present invention.

[0059] Figure 5 The present invention provides a flow chart for determining whether a container truck is lifted according to the lifting height of a container scanning line.

[0060] Figure 6 This is a schematic diagram of the entire point cloud of the container truck provided by the present invention connected with the container.

[0061] Figure 7 This is a schematic diagram of the container being separated from the container truck after being lifted to a certain height provided by the present invention.

[0062] Figure 8 This is a schematic diagram of determining whether a container truck is lifted according to the lifting height of the container truck provided by the present invention.

[0063] Figure 9 The present invention provides a flow chart for correcting the lifting height of the current container truck.

[0064] Figure 10 This is a flow chart for calculating the horizontal deviation rate of the current container truck provided by the present invention.

[0065] Figure 11 This is a schematic diagram of detecting anomalies through the horizontal offset rate of the truck point cloud provided by the present invention.

[0066] Figure 12 The present invention provides a flow chart for determining whether the current container truck is lifted according to the normal lifting height of the current container truck and the horizontal deviation rate of the current container truck.

[0067] Figure 13 This is a schematic diagram of the connection between the point cloud of the container truck just lifted by the spreader provided by the present invention and the container.

[0068] Figure 14This is a schematic diagram of the point cloud separation of the connection between the truck and the container when the spreader provided by the present invention is lifted to a certain height.

[0069] Figure 15 This is a schematic diagram of the present invention before lifting with the single lock buckle on the side away from the radar unfastened.

[0070] Figure 16 This is a structural block diagram of the anti-lifting detection device based on single-line laser radar provided by the present invention.

[0071] Figure 17 This is a structural block diagram of the anti-lifting detection system based on single-line laser radar provided by the present invention. DETAILED DESCRIPTION

[0072] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention may be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0073] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described 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 making creative efforts should fall within the scope of protection of the present invention.

[0074] It should be noted that the terms "first," "second," and the like in the specification and claims of the present invention and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate for the embodiments of the present invention described herein. In addition, the terms "including," "having," and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to these processes, methods, products, or apparatuses.

[0075] In this embodiment, a single-line laser radar-based anti-lifting detection method is provided. Figure 1 FIG. 1 is a flow chart of a method for detecting anti-lifting based on a single-line laser radar according to an embodiment of the present invention. Figure 1 Shown, including:

[0076] S100, obtaining laser point cloud data information of a single-line laser radar;

[0077] In an embodiment of the present invention, a single-line laser radar is installed on the container, and laser point cloud data information is formed through the scanning information of the single-line laser radar.

[0078] S200, pre-processing the laser point cloud data information to obtain a target point cloud area with container scanning line information;

[0079] The laser point cloud data information is preprocessed, specifically the laser point cloud data information can be clustered and linearly fitted, and the target point cloud area with container scanning line information can be extracted.

[0080] S300, determining whether the container and the container truck are separated based on the search results of the container truck scanning point cloud within the target point cloud area;

[0081] In an embodiment of the present invention, whether the container and the container truck are separated is determined based on the container truck scanning point cloud search results within the target point cloud area. It should be understood that the container truck scanning point cloud search results within the target point cloud area may specifically include the existence of the container truck scanning point cloud or the absence of the container truck scanning point cloud.

[0082] S400: When it is determined that the container and the container truck are not separated, determining whether the container truck is lifted according to the lifting height of the container scanning line;

[0083] When it is determined based on the search results of the container truck scanning point cloud that the current container and the container truck are not separated, the lifting height of the container scanning line is calculated to determine whether the container truck is lifted.

[0084] S500: When it is determined that the container is separated from the container truck, determining whether the container truck is lifted according to the lifting height of the container truck;

[0085] When it is determined that the current container and the container truck are separated according to the search results of the container truck scanning point cloud, it is determined whether the container truck is lifted according to the lifting height of the container truck and whether the lifting height of the container truck is abnormal.

[0086] S600: When it is determined that the container truck is lifted, generate and send an alarm signal.

[0087] It should be understood that when it is determined that the container truck is lifted, an alarm signal is generated and sent to the controller.

[0088] In summary, the anti-lifting detection method based on single-line laser radar provided by the present invention obtains the point cloud information of the container and the container truck in real time through the single-line laser radar, and analyzes the separation status of the container and the container truck pallet, and triggers an alarm signal when it is determined that the container truck is lifted. This avoids the accident that the crane accidentally lifts the container and the container truck pallet together when unloading the container, improves the safety and efficiency during operation, and the anti-lifting detection method based on single-line laser radar can realize anti-lifting detection efficiently and reliably.

[0089] In an embodiment of the present invention, the laser point cloud data information is preprocessed, such as Figure 2 Shown, including:

[0090] S210, performing clustering processing on the laser point cloud data information to obtain multiple laser point cloud clusters;

[0091] Specifically, the obtained laser point cloud data information is clustered using the DBSCAN algorithm to obtain multiple point cloud clusters.

[0092] S220, performing linear fitting on each laser point cloud cluster to obtain a target point cloud region with container scanning line information;

[0093] In this embodiment of the present invention, a linear fit is performed on each point cloud cluster. Specifically, to avoid the influence of outliers in the point cloud cluster on the fitting results, the RANSAC algorithm is used to remove outliers before fitting. Then, the least squares method is used to fit a straight line. The formula for the straight line fitting is as follows:

[0094]

[0095] Among them, k and b represent the slope and intercept of the fitted straight line, n represents the number of points in the point cloud cluster, and x i ,y i They represent the horizontal and vertical coordinates of the i-th point in the point cloud cluster respectively.

[0096] S230. Searching in the target point cloud region with the container scanning information based on prior knowledge of the container's geometric features to obtain a container scanning line;

[0097] Specifically, the length and direction of the container scanning line can be roughly estimated based on the installation position of the lidar and the height of the container. Using these two prior features as indicators, the scanning line L corresponding to the container can be extracted from multiple point cloud clusters, as shown in the following example: Figure 3 shown.

[0098] S240, determining a container truck search area according to the container scanning line;

[0099] In an embodiment of the present invention, the rectangular space below the container scanning line is determined as the container truck search area. A search is performed within the container truck search area. If a cluster of a certain size exists, it is the scanning point cloud of the container truck, indicating that the container and the container truck are separated.

[0100] Specifically, the scanning point cloud of the container truck is located below the container scanning line. A rectangular area is defined by the horizontal line where the lower edge endpoint of the container scanning line is located, the horizontal line 0.5m below, the vertical line 2.5m to the left, and the vertical line 0.5m to the right. Figure 3 As shown, all points within the rectangular area are extracted.

[0101] S250: Search the container truck scanning point cloud in the container truck search area to obtain the container truck scanning point cloud search result.

[0102] It should be noted that in this embodiment of the present invention, to prevent the influence of noise points on the extraction of container truck height features, the DBSCAN algorithm is used to cluster the extracted container truck scan point cloud. By retaining all the resulting point cloud clusters, sparse and scattered noise points can be eliminated. The point set consisting of all the points in the retained point cloud clusters is denoted as T. If the number of points in T is greater than 10, T is considered to be a valid container truck scan point cloud.

[0103] In the embodiment of the present invention, it is determined whether the container and the truck are separated based on the search results of the truck scanning point cloud within the target point cloud area. Figure 4 Shown, including:

[0104] S310, determining whether there is a container truck scanning point cloud within the target point cloud area;

[0105] S320: If there is a container truck scanning point cloud, determine that the container is separated from the container truck;

[0106] S330: If there is no container truck scanning point cloud, it is determined that the container and the container truck are not separated.

[0107] It should be understood that whether the container and the container truck are separated is determined based on whether the container truck scanning point cloud can be extracted in the target area. When the container truck scanning point cloud exists in the target point cloud area, it is determined that the container and the container truck are separated; otherwise, it is determined that the container and the container truck are not separated.

[0108] In this embodiment of the present invention, if the scan point cloud of the container truck is absent, it indicates that the container and the container truck have not been separated. In this case, the lifting height of the lower edge endpoint of the container scanning line is observed. If it exceeds a predetermined threshold, the container truck is determined to be lifted and an alarm signal is sent to the controller.

[0109] Specifically, when it is determined that the container and the container truck are not separated, it is determined whether the container truck is lifted according to the lifting height of the container scanning line, such as Figure 5 Shown, including:

[0110] S410: When it is determined that the container and the container truck are not separated, calculating the lifting height of the lower edge endpoint of the container scanning line;

[0111] S420: If the lifting height of the lower edge endpoint of the container scanning line is greater than a preset safety threshold, it is determined that the container truck is lifted;

[0112] S430: If the lifting height of the lower edge endpoint of the container scanning line is not greater than a preset safety threshold, it is determined that the container truck is not lifted.

[0113] like Figure 6 As shown in Figure 1, when the spreader just starts to lift, the container scan line and all the point clouds of the container truck are connected together. The extracted container scan line L contains the scan point clouds of the container and the container truck. The height of the lower edge endpoint of L is h L , then h L It can be roughly regarded as the height of the bottom of the truck. Let the height of the bottom of the truck before lifting be h1, then the real-time lifting height of the truck Δh=h L -h1; If Δh>thresh1, it is determined that the container truck is lifted and an alarm signal should be sent to the controller immediately for protection. If it is a normal working condition, after the spreader is lifted to a certain height, the container and the container truck will separate, such as Figure 7 As shown, the container truck will be detected, and whether the container truck is lifted is determined based on the lifting height of the container truck.

[0114] In the embodiment of the present invention, when it is determined that the container is separated from the container truck, it is determined whether the container truck is lifted according to the lifting height of the container truck, such as Figure 8 Shown, including:

[0115] S510: When it is determined that the container is separated from the truck, determine whether the current truck's lifting height is a normal lifting height based on the truck's top lifting height and the difference between the top lifting heights of two adjacent trucks;

[0116] It should be noted that when it is determined that the container is separated from the truck, it is necessary to further determine whether the lifting height of the current truck is normal, so as to avoid the phenomenon that although the scanning point cloud of the truck is extracted, the lifting height of the top of the truck increases sharply due to the connection between other parts of the truck and the container, thereby causing a false alarm. Therefore, it is necessary to determine whether the lifting height of the current truck is normal based on the top lifting height and the difference between the top lifting heights of two adjacent truck frames.

[0117] If the top lifting height of the container truck is greater than the preset safety threshold, and the difference in the top lifting heights of two adjacent container trucks is greater than the preset difference threshold, it is determined that the lifting height of the current container truck is abnormal. Conversely, if the difference in the top lifting heights of two adjacent container trucks is not greater than the preset difference threshold, it is determined that the lifting height of the current container truck is normal.

[0118] In an embodiment of the present invention, the calculation process of the top lifting height of the container truck includes:

[0119] The height of the top of the container truck before lifting the spreader As a reference height, the same method can be used to obtain the height h of the top of the real-time truck point cloud. top During the lifting process of the spreader, calculate the lifting height h of the top of the container truck hoist =h top -h top_ref , if h hoist If the preset safety threshold h_threshold is exceeded, it is determined that the container truck is lifted and an alarm signal should be sent to the PLC immediately for protection. In the embodiment of the present invention, based on experience, h_threshold is set to 0.18m.

[0120] S520: If the lifting height of the current container truck is abnormal, correct the lifting height of the current container truck and obtain a normal lifting height after correction;

[0121] In an embodiment of the present invention, if the lifting height of the current container truck is abnormal, the lifting height of the current container truck is corrected to avoid subsequent false alarms.

[0122] Specifically, the lifting height of the current container truck is corrected, such as Figure 9 Shown, including:

[0123] S521, respectively calculating the top height of the previous frame and the top height of the current frame of the container truck, and calculating the bottom height of the previous frame and the bottom height of the current frame of the container;

[0124] Specifically, the height h of the top of the container truck in the previous frame is calculated according to the calculation process of the top lifting height of the container truck in the previous text. top_last .

[0125] According to the container scanning line L extracted above, the bottom height of the container is the height of the lower edge endpoint of L, from which the bottom height of the container in the previous frame h can be obtained. container_bottom_last .

[0126] Therefore, the height h of the top of the truck in the current frame can be calculated top , height of the bottom of the container h container_bottom .

[0127] S522: Determine whether the point cloud of the container truck is separated from the container based on a top height difference between a top height of the current frame of the container truck and a top height of a previous frame, and a difference between the top height difference and a bottom height difference of the container;

[0128] If in the current frame, h top -h top_last >0.05 and |h top -h top_last -(h container_bottom -h container_bottom_last )|<0.03If both conditions are met at the same time, it means that part of the point cloud of the truck is separated from the container, such as Figure 13 and Figure 14 As shown, Figure 13 The point cloud of the container truck just lifted by the spreader is connected to the container. Figure 14 The figure shows the separation of the point cloud of the connection between the truck and the container when the spreader is lifted to a certain height.

[0129] S523. If it is determined that part of the point cloud of the container truck is separated from the container, the reference height of the container truck and the top height of the previous frame of the container truck are reset to the top height of the current frame of the container truck, and the lifting height of the top of the container truck is reset to 0;

[0130] In the embodiment of the present invention, when it is determined that part of the point cloud of the container truck is separated from the container, h top_ref With h top_last Reset to h top , h hoi Set to 0.

[0131] S524: Record the top height of the truck and the bottom height of the container in the current frame.

[0132] Specifically, record the height between the top of the truck and the bottom of the container in the current frame, and set h container_bottom_last Updated to h container_bottom , h top_last Updated to h top .

[0133] S530: If the current lifting height of the container truck is the normal lifting height, calculate the horizontal deviation rate of the current container truck;

[0134] It should be noted that under certain specific working conditions (such as the side of the container truck away from the laser radar is lifted, such as Figure 15 As shown in FIG, even if the spreader has been lifted to a sufficient height, the lifting height of the container truck top will not exceed the set safety threshold, resulting in missed reports. To avoid missed reports, in an embodiment of the present invention, the horizontal deviation rate of the current container truck is calculated, such as Figure 10 Shown, including:

[0135] S531, construct a standardized reference point set for the card point cloud;

[0136] Specifically, the reference benchmark of the container truck point cloud is established: when the container truck is in a stationary and unlifted state, a standardized reference point set R is established, such as Figure 11 The blue point cloud shown is constructed using R’s KD-Tree spatial index.

[0137] S532. Acquire a real-time point cloud of the container truck during the lifting process;

[0138] Specifically, the real-time point cloud index of the container truck is constructed: the real-time point cloud T of the container truck during the lifting process is obtained, such as Figure 8 The red point cloud in and construct the KD-Tree spatial index of T.

[0139] S533, matching each point in the standardized reference point set in the real-time point cloud of the container truck and matching each point in the real-time point cloud of the container truck in the standardized point set to obtain a valid matching result and an offset matching result for bidirectional matching;

[0140] In the embodiment of the present invention, a bidirectional matching analysis is performed to achieve an accurate assessment of whether the truck is offset. Specifically, in the first matching stage: for each point r in the reference point set R i , perform a circular search with a radius of 0.1m in the real-time point set T. If there is a point t that meets the conditions j ∈T, such that ||r i -t j ||<0.1m, the valid match counter C_match increases, and when ||r i -t j When ||<0.025m, the offset counter C_offset increases; the second matching stage: for each point t in the real-time point set T k , perform a circular search with a radius of 0.1m in the reference point set R, if there is a point r that meets the conditions m ∈R, such that ||t k -r m ||<0.1m, the valid match counter C_match increases. When ||t k -r m When ||<0.025m, the offset counter C_offset increases.

[0141] S534: Perform dynamic offset evaluation based on the offset matching result and the valid matching result to obtain the horizontal offset rate of the current container truck.

[0142] Specifically, dynamic offset assessment involves calculating a composite offset ratio, η, which equals C_offset / C_match. When η exceeds a preset offset ratio threshold, η_threshold, the container truck is deemed to be lifted, and an alarm signal is immediately sent to the PLC for protection. It should be noted that the preset offset ratio threshold, η_threshold, in this embodiment of the present invention is empirically set to 0.4.

[0143] S540: Determine whether the current container truck is lifted according to the normal lifting height of the current container truck and the horizontal deviation rate of the current container truck.

[0144] Whether the container truck is lifted is determined based on whether the container truck is horizontally offset at the normal lifting height of the container truck. Specifically, whether the current container truck is lifted is determined based on the normal lifting height of the current container truck and the horizontal offset rate of the current container truck, such as Figure 12 Shown, including:

[0145] S541, comparing the normal lifting height of the current container truck with a preset safety threshold, and comparing the horizontal deviation rate of the current container truck with a preset deviation rate threshold;

[0146] S542: If the normal lifting height of the current container truck is greater than a preset safety threshold, or the horizontal deviation rate of the current container truck is greater than a preset deviation rate threshold, determine that the container truck is lifted;

[0147] S543: If the normal lifting height of the current container truck is not greater than the preset safety threshold, and the horizontal deviation rate of the current container truck is not greater than the preset deviation rate threshold, it is determined that the container truck is not lifted.

[0148] It should be noted that, in the embodiment of the present invention, whether the container truck is lifted is detected by taking into account the abnormality of the container truck's lifting height and the container truck's deviation, that is, by comprehensively considering the specific working conditions of the container truck, thereby being more in line with actual application scenarios and effectively avoiding accidents.

[0149] Therefore, the anti-lifting detection method based on a single-line laser radar provided by the present invention acquires the point cloud information of the container and the container truck in real time through the laser radar, and analyzes the separation status of the container and the container truck pallet in combination with an algorithm. Moreover, due to the comprehensive consideration of various specific working conditions of the container truck, it can more accurately detect the abnormality of the container truck. When an abnormality is detected, an alarm signal is triggered to avoid accidents and improve the safety and efficiency during operation. In summary, the anti-lifting detection method based on a single-line laser radar provided by the present invention can handle specific working conditions where the container is connected to part or all of the container truck point cloud, effectively reducing the false alarm rate and the missed alarm rate; for some abnormal working conditions where the lifting height of the container truck changes slowly, the horizontal offset rate estimation method based on bidirectional stable point screening can timely capture the occurrence of abnormal working conditions, thereby avoiding danger earlier.

[0150] As another embodiment of the present invention, a single-line laser radar-based anti-lifting detection device 10 is provided for implementing the aforementioned single-line laser radar-based anti-lifting detection method, wherein: Figure 16 Shown, including:

[0151] The acquisition module 100 is used to obtain laser point cloud data information of a single-line laser radar;

[0152] A preprocessing module 200 is used to preprocess the laser point cloud data information to obtain a target point cloud area with container scanning line information;

[0153] A determination module 300 is configured to determine whether the container and the container truck are separated based on the search results of the container truck scanning point cloud within the target point cloud area;

[0154] The non-separation determination module 400 is used to determine whether the container truck is lifted according to the lifting height of the container scanning line when it is determined that the container and the container truck are not separated;

[0155] A separation determination module 500 is used to determine whether the container truck is lifted according to the lifting height of the container truck when it is determined that the container is separated from the container truck;

[0156] The alarm module 600 is configured to generate and send an alarm signal when it is determined that the container truck is lifted.

[0157] The anti-lifting detection device based on a single-line laser radar provided by the present invention obtains point cloud information of the container and the container truck in real time through the single-line laser radar, and analyzes the separation status of the container and the container truck pallet, and triggers an alarm signal when it is determined that the container truck is lifted, thereby avoiding the accident of the crane accidentally lifting the container and the container truck pallet together when unloading the container, improving the safety and efficiency during operation, and the anti-lifting detection method based on the single-line laser radar can realize anti-lifting detection efficiently and reliably.

[0158] Regarding the specific working process of the anti-lifting detection device based on the single-line laser radar provided by the present invention, please refer to the description of the anti-lifting detection method based on the single-line laser radar in the previous text, which will not be repeated here.

[0159] As another embodiment of the present invention, an anti-lifting detection system 1 based on a single-line laser radar is provided, which includes: a controller 20 and the anti-lifting detection device 10 based on the single-line laser radar as described above, the controller 20 is communicatively connected with the anti-lifting detection device 10 based on the single-line laser radar, and the anti-lifting detection device 10 based on the single-line laser radar can generate an alarm signal when it is determined that the container truck is lifted and send the alarm signal to the controller.

[0160] The anti-lifting detection system based on single-line laser radar provided by the present invention adopts the anti-lifting detection device based on single-line laser radar mentioned above, obtains point cloud information of containers and container trucks in real time through single-line laser radar, and analyzes the separation status of containers and container truck pallets, and triggers an alarm signal when it is determined that the container truck is lifted, thereby avoiding the accident of the crane accidentally lifting the container and the container truck pallet together when unloading the container, improving the safety and efficiency during operation, and the anti-lifting detection method based on single-line laser radar can realize anti-lifting detection efficiently and reliably.

[0161] In the embodiment of the present invention, the controller 20 may specifically be a PLC.

[0162] Regarding the specific working process of the anti-lifting detection device based on the single-line laser radar provided by the present invention, please refer to the description of the anti-lifting detection method based on the single-line laser radar in the previous text, which will not be repeated here.

[0163] It will be understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present invention, and the present invention is not limited thereto. Those skilled in the art will appreciate that various modifications and improvements can be made without departing from the spirit and substance of the present invention, and such modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A single-line laser radar-based anti-lifting detection method, characterized in that: include: Obtain laser point cloud data information of single-line laser radar; Preprocessing the laser point cloud data information to obtain a target point cloud area with container scanning line information; Determine whether the container and the truck are separated based on the search results of the truck scanning point cloud within the target point cloud area; When it is determined that the container and the container truck are not separated, determining whether the container truck is lifted according to the lifting height of the container scanning line; When it is determined that the container is separated from the container truck, whether the container truck is lifted is determined based on the lifting height of the container truck; When it is determined that the container truck is lifted, an alarm signal is generated and sent.

2. The anti-lifting detection method based on single-line laser radar according to claim 1 is characterized in that: Determining whether the container and the truck are separated based on the search results of the truck scanning point cloud within the target point cloud area includes: Determine whether there is a truck scanning point cloud within the target point cloud area; If there is a container truck scanning point cloud, it is determined that the container is separated from the container truck; If there is no container truck scanning point cloud, it is determined that the container and the container truck are not separated.

3. The anti-lifting detection method based on single-line laser radar according to claim 1 is characterized in that: When it is determined that the container and the container truck are not separated, determining whether the container truck is lifted according to the lifting height of the container scanning line includes: When it is determined that the container and the container truck are not separated, calculating the lifting height of the lower edge endpoint of the container scanning line; If the lifting height of the lower edge endpoint of the container scanning line is greater than a preset safety threshold, it is determined that the container truck is lifted; If the lifting height of the lower edge endpoint of the container scanning line is not greater than a preset safety threshold, it is determined that the container truck is not lifted.

4. The anti-lifting detection method based on single-line laser radar according to claim 1 is characterized in that: When it is determined that the container is separated from the truck, the truck is lifted according to its lifting height, including: When it is determined that the container is separated from the truck, whether the current truck's lifting height is normal is determined based on the truck's top lifting height and the difference between the top lifting heights of two adjacent trucks. If the lifting height of the current container truck is abnormal, the lifting height of the current container truck is corrected and the corrected normal lifting height is obtained; If the current lifting height of the container truck is the normal lifting height, calculate the horizontal deviation rate of the current container truck; Whether the current container truck is lifted is determined based on the normal lifting height of the current container truck and the horizontal deviation rate of the current container truck.

5. The anti-lifting detection method based on single-line laser radar according to claim 4 is characterized in that: Determine whether the current container truck is lifted based on its normal lifting height and horizontal deviation rate, including: Comparing the normal lifting height of the current container truck with a preset safety threshold, and comparing the horizontal deviation rate of the current container truck with a preset deviation rate threshold; If the normal lifting height of the current container truck is greater than a preset safety threshold, or the horizontal deviation rate of the current container truck is greater than a preset deviation rate threshold, it is determined that the container truck is lifted; If the normal lifting height of the current container truck is not greater than the preset safety threshold, and the horizontal deviation rate of the current container truck is not greater than the preset deviation rate threshold, it is determined that the container truck is not lifted.

6. The anti-lifting detection method based on single-line laser radar according to claim 4 is characterized in that: Calculate the horizontal deviation rate of the current container truck, including: Construct a standardized reference point set for the card point cloud; Obtain real-time point cloud of the container truck during the lifting process; Matching each point in the container truck real-time point cloud according to the standardized reference point set and matching each point in the container truck real-time point cloud with the standardized point set to obtain a valid matching result and an offset matching result for bidirectional matching; A dynamic offset evaluation is performed based on the offset matching result and the effective matching result to obtain the horizontal offset rate of the current container truck.

7. The anti-lifting detection method based on single-line laser radar according to claim 4 is characterized in that: Correct the current lifting height of the container truck, including: Calculate the top height of the previous frame and the top height of the current frame of the container truck, and calculate the bottom height of the previous frame and the bottom height of the current frame of the container; Determine whether the point cloud of the container truck is separated from the container based on the top height difference between the top height of the current frame of the container truck and the top height of the previous frame, and the difference between the top height difference and the bottom height difference of the container; If it is determined that part of the point cloud of the container truck is separated from the container, the reference height of the container truck and the top height of the previous frame of the container truck are reset to the top height of the current frame of the container truck, and the lifting height of the top of the container truck is reset to 0; Record the top height of the truck and the bottom height of the container in the current frame.

8. The anti-lifting detection method based on a single-line laser radar according to any one of claims 1 to 7, characterized in that: Preprocessing the laser point cloud data information includes: performing clustering processing on the laser point cloud data information to obtain a plurality of laser point cloud clusters; Linear fitting is performed on each laser point cloud cluster to obtain the target point cloud area with container scanning line information; Searching in the target point cloud area with the container scanning information based on the prior knowledge of the container's geometric features to obtain the container scanning line; Determine a container truck search area according to the container scanning line; The container truck scanning point cloud is searched in the container truck search area to obtain the container truck scanning point cloud search result.

9. An anti-lifting detection device based on a single-line laser radar, used to implement the anti-lifting detection method based on a single-line laser radar according to any one of claims 1 to 8, characterized in that: include: Acquisition module, used to obtain laser point cloud data information of single-line laser radar; A preprocessing module, configured to preprocess the laser point cloud data information to obtain a target point cloud area with container scanning line information; A determination module, configured to determine whether the container and the container truck are separated based on the search results of the container truck scanning point cloud within the target point cloud area; a non-separation determination module, configured to determine whether the container truck is lifted based on the lifting height of the container scanning line when it is determined that the container and the container truck are not separated; A separation determination module is used to determine whether the container truck is lifted according to the lifting height of the container truck when it is determined that the container is separated from the container truck; The alarm module is used to generate and send an alarm signal when it is determined that the container truck is lifted.

10. An anti-lifting detection system based on a single-line laser radar, characterized in that: include: The controller is in communication connection with the anti-lifting detection device based on the single-line laser radar as described in claim 9, and the anti-lifting detection device based on the single-line laser radar can generate an alarm signal and send the alarm signal to the controller when it determines that the container truck is lifted.

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