Gis-based off-road mobile machine work track tracing method and system

Abstract

This application provides a GIS-based method and system for tracing the operational trajectory of non-road mobile machinery, relating to the fields of geographic information processing and machinery operation supervision. Specifically, this application generates a spatiotemporal trajectory of the machinery by acquiring its location and lifting stress data; projects this trajectory onto a yard elevation model to generate a model-mapped trajectory; reads synchronous lifting stress data along the model-mapped trajectory; separates the model-mapped trajectory at points where the lifting stress data experiences continuous steps and the spatial coordinates are located at container storage nodes, extracting the initial full-load trajectory; further, it segments the initial full-load trajectory based on the volume reduction of the container's occupied area along the initial full-load trajectory, discarding idling trajectories and retaining valid full-load trajectories; finally, it connects all valid full-load trajectories in chronological order of data collection to form the actual operational trajectory. This application can accurately reconstruct the actual container flow process and improve the reliability of operational trajectory traceability.

Description

Technical Field

[0001] This application relates to the fields of geographic information processing and machinery operation supervision technology, and in particular to a GIS-based method and system for tracing the operation trajectory of non-road mobile machinery. Background Technology

[0002] Non-road mobile machinery refers to engineering machinery and equipment used in non-road locations such as ports, storage yards, mines, and construction sites for material handling, loading, unloading, and stacking operations. Common examples include reach stackers, stackers, empty container stackers, gantry cranes, wheel loaders, and forklifts. In port container handling operations, non-road mobile machinery is responsible for the transfer of containers within the storage yard and between the storage yard and the terminal / gate. Accurate tracking of their operational trajectories is crucial for optimizing storage yard scheduling, calculating workload, verifying energy consumption, tracking carbon emissions, and holding violators accountable.

[0003] Geographic Information System (GIS) is a computer system used to collect, store, manage, analyze, and display data related to spatial location. Combining GIS with the operation of non-road mobile machinery allows for the visualization and historical tracking of the machinery's movement status in the form of spatial geographic coordinates, making it an important technological means for the current digitalization of ports and the construction of smart storage yards.

[0004] Existing methods for recording the operational trajectories of non-road mobile machinery largely rely on the equipment's built-in Global Navigation Satellite System (GNSS) positioning module. The location points collected by the positioning module at a fixed sampling period are connected sequentially over time to form a continuous operational trajectory. However, in developing this application, the inventors discovered the following shortcomings in existing methods: First, trajectories formed solely based on position sequences cannot distinguish between different operational states such as unloaded movement, fully loaded circulation, or stationary idling, resulting in a large number of invalid paths unrelated to container circulation within the trajectory. Second, due to the high stacking density of containers in the yard and the strong three-dimensionality of the machinery's operational space, planar trajectories cannot reflect the vertical positional changes of containers, leading to low spatial fidelity in the operational process. Third, some machinery operators may engage in fictitious round trips or empty bucket operations to meet workload targets; relying solely on position trajectories is insufficient to eliminate such invalid operations from the actual circulation process, thus affecting the objectivity and accuracy of supervision. Summary of the Invention

[0005] In view of this, the present application provides a GIS-based method and system for tracing the operation trajectory of non-road mobile machinery, in order to overcome the problems of existing operation trajectory recording methods being unable to effectively distinguish between valid and invalid operations, having low spatial fidelity, and being easily interfered with by false operations, thereby obtaining an operation trajectory that can truly reflect the container circulation process.

[0006] In a first aspect, embodiments of this application provide a GIS-based method for tracing the operational trajectory of non-road mobile machinery, including:

[0007] The machine position data collected by the positioning module on the non-road mobile machinery and the lifting stress data collected by the lifting assembly of the non-road mobile machinery are obtained. The acquisition time corresponding to the machine position data and the lifting stress data is extracted. The machine position data and the lifting stress data are synchronized according to the acquisition time to generate the machine spatiotemporal trajectory.

[0008] Retrieve the container yard elevation model that records the distribution of containers in the port container transfer yard from the geographic information system, and project the mechanical spatiotemporal trajectory onto the container yard elevation model according to spatial coordinates to generate the model mapping trajectory.

[0009] Read the synchronous lifting stress data along the model mapping trajectory. When the lifting stress data makes a continuous step and the spatial coordinate is located at the container storage node of the yard elevation model, separate the model mapping trajectory and extract the initial full-load trajectory of the lifting component under force.

[0010] Calculate the volume occupied by the container in the area traversed by the initial full-load trajectory in the yard elevation model. According to the volume reduction of the container's occupied volume within the corresponding time period of the initial full-load trajectory, divide the initial full-load trajectory, eliminate idling movement trajectories that do not cause changes in the physical space, and retain the effective full-load trajectory.

[0011] All valid full-load trajectories are connected in chronological order of collection time, and combined to form the actual operation trajectory of container flow. The actual operation trajectory is then imported into the geographic information system for storage.

[0012] Optionally, the mechanical position data and the lifting stress data are synchronized according to the acquisition time to generate a mechanical spatiotemporal trajectory, including:

[0013] Extract the positioning timestamp of the mechanical position data and the force timestamp of the lifting stress data;

[0014] The positioning timestamp is established as the synchronization time reference axis;

[0015] According to the time flow nodes on the synchronous time reference axis, the lifting stress data is filled with nodes so that the time node density of the lifting stress data is consistent with the mechanical position data.

[0016] The mechanical position data and the lifting stress data at the same time node on the synchronous time reference axis are combined and bound to generate a three-dimensional spatial node with force values.

[0017] All three-dimensional spatial nodes with force values ​​are connected according to the time sequence of the synchronous time reference axis to generate a mechanical spatiotemporal trajectory.

[0018] Optionally, the mechanical spatiotemporal trajectory is projected onto the stockpile elevation model according to spatial coordinates to generate a model mapping trajectory, including:

[0019] The basic grid coordinate system of the aforementioned stockpile elevation model is analyzed;

[0020] The spatial coordinates of the mechanical spatiotemporal trajectory are converted into grid node coordinates under the basic grid coordinate system;

[0021] Search the three-dimensional grid cell into which the coordinates of the grid node fall in the stockyard elevation model;

[0022] Following the movement of the mechanical spatiotemporal trajectory, the mechanical spatiotemporal trajectory is nested and fitted onto the surface spatial contour of the three-dimensional mesh unit to output a model mapping trajectory with embedded container spatial topological distribution features.

[0023] Optionally, synchronous lifting stress data is read along the model mapping trajectory. When the lifting stress data experiences continuous step changes and the spatial coordinates are located at the container storage node of the yard elevation model, the model mapping trajectory is separated to extract the initial full-load trajectory of the lifting assembly under stress, including:

[0024] The synchronized lifting stress data is read point by point along the path of the model mapping trajectory;

[0025] The trend of stress value change between adjacent reading points is detected, and the segment in the lifting stress data that meets the first preset condition is marked as the stress step segment;

[0026] Extract the starting coordinates of the stress step section and determine whether the starting coordinates fall within the range of the container storage node that records the container stacking attributes in the yard elevation model.

[0027] If it falls within the container storage node range that records container stacking attributes, the starting point of the stress step section is taken as the separation start point, and the physical inflection point where the lifting stress data changes from a stable state to a decreasing state is taken as the separation end point.

[0028] If the container does not fall within the range of the container storage node that records the container stacking attributes, it is determined to be an invalid stress fluctuation, and the process returns to the step of reading the synchronized lifting stress data point by point along the path of the model mapping trajectory.

[0029] Extract the model mapping trajectory segment between the separation start end and the separation end end as the initial full-load trajectory.

[0030] Optionally, the trend of stress value changes between adjacent reading points is detected, and the segment in the lifting stress data that meets the first preset condition is marked as a stress step segment, including:

[0031] The lifting stress data is divided into moving observation windows that slide at fixed step sizes;

[0032] The number of peak nodes showing an increase in stress value within the moving observation window is counted.

[0033] The cumulative stress increment is obtained by summing the stress increase difference between two adjacent wave crest nodes;

[0034] Based on the inherent force fluctuation amplitude generated by the gravity of the lifting assembly's own physical structure, when the cumulative force increment exhibits a physical abrupt increase exceeding the inherent force fluctuation amplitude, it is determined that an actual external cargo load has been generated.

[0035] The segment containing the moving observation window that generates actual external cargo load and whose subsequent stress value fluctuations remain within a fixed and stable range is identified as the stress step zone.

[0036] Optionally, the volume occupied by the container in the area traversed by the initial full-load trajectory in the yard elevation model is calculated. Based on the volume reduction of the container's occupied volume within the corresponding time period of the initial full-load trajectory, the initial full-load trajectory is segmented, and idling movement trajectories that do not cause changes in physical space are discarded, retaining the valid full-load trajectories, including:

[0037] In the stockyard elevation model, delineate a three-dimensional bounding box that covers the initial full-load trajectory.

[0038] At the start of the time period corresponding to the initial full-load trajectory, the initial occupied volume of the entity stack inside the three-dimensional bounding box of space is read.

[0039] At the end of the time period corresponding to the initial full-load trajectory, the final occupied volume of the stacked entities inside the three-dimensional bounding box of the space is read.

[0040] Subtracting the final occupied volume from the initial occupied volume yields the reduction in the volume occupied by the box.

[0041] When the volume reduction meets the second preset condition, the corresponding segment is determined to be the idling movement trajectory and spatial cut-off is performed, while the remaining effective segment is retained as the effective full-load trajectory.

[0042] Optionally, all valid full-load trajectories are connected in chronological order of collection time to form the actual operation trajectory of container flow, and the actual operation trajectory is imported into the geographic information system for storage, including:

[0043] From all valid fully loaded trajectories, identify the set of trajectories belonging to the same non-road mobile machinery equipment identifier;

[0044] Read the acquisition time bound to the start and end endpoints of each valid full-load trajectory in the trajectory set;

[0045] According to the rule of collecting data in chronological order, the valid fully loaded trajectories belonging to the same non-road mobile machinery equipment are arranged in timeline;

[0046] Spatial lines are used to connect the terminating endpoint of the first-ordered valid full-load trajectory to the starting endpoint of the second-ordered valid full-load trajectory, thus piecing together the actual operation trajectory.

[0047] Record the identification of the non-road mobile machinery equipment corresponding to the actual operation trajectory and import it into the traceability database of the geographic information system for persistent storage.

[0048] Secondly, this application provides a GIS-based non-road mobile machinery operation trajectory tracing system, including:

[0049] The acquisition module is used to acquire the mechanical position data collected by the positioning module on the non-road mobile machinery and the lifting stress data collected by the lifting assembly of the non-road mobile machinery, extract the acquisition time corresponding to the mechanical position data and the lifting stress data, synchronize the mechanical position data and the lifting stress data according to the acquisition time, and generate the mechanical spatiotemporal trajectory.

[0050] The model mapping module is used to retrieve the yard elevation model that records the distribution of containers in the port container transfer yard in the geographic information system, and project the mechanical spatiotemporal trajectory into the yard elevation model according to the spatial coordinates to generate the model mapping trajectory.

[0051] The separation module is used to read synchronous lifting stress data along the model mapping trajectory. When the lifting stress data experiences continuous step changes and the spatial coordinates are located at the container storage node of the yard elevation model, the model mapping trajectory is separated to extract the initial full-load trajectory of the lifting component under force.

[0052] The calculation module is used to calculate the volume occupied by the container in the area through which the initial full-load trajectory passes in the yard elevation model. According to the volume reduction of the container volume occupied during the corresponding time period of the initial full-load trajectory, the initial full-load trajectory is divided, and the idle movement trajectory that does not cause changes in the physical space is eliminated, and the effective full-load trajectory is retained.

[0053] The connection module is used to connect all valid full-load trajectories in chronological order of collection time, combine them into the actual operation trajectory of container flow, and import the actual operation trajectory into the geographic information system for storage.

[0054] Thirdly, embodiments of this application provide a computing device, including a processing component and a storage component; the storage component stores one or more computer instructions; the one or more computer instructions are invoked and executed by the processing component to realize the above-mentioned GIS-based non-road mobile machinery operation trajectory tracing method.

[0055] Fourthly, embodiments of this application provide a computer storage medium storing a computer program, which, when executed by a computer, implements the above-described GIS-based method for tracing the operation trajectory of non-road mobile machinery.

[0056] Compared with the prior art, the embodiments of this application have the following beneficial effects:

[0057] First, this application generates a mechanical spatiotemporal trajectory that simultaneously carries spatial coordinates and load status information by synchronously binding the mechanical position data output by the positioning module with the lifting stress data output by the lifting component according to the acquisition time. This solves the problem that the existing solution only expresses the operation process with planar position points and cannot distinguish between unloaded movement and fully loaded flow, so that the operation status judgment has a quantifiable physical basis.

[0058] Second, this application utilizes the three-dimensional distribution characteristics of containers recorded in GIS by the yard elevation model to nest and fit the mechanical spatiotemporal trajectory onto the three-dimensional grid cells of the model. The generated model mapping trajectory contains the spatial topology information of container stacking, which can fully reflect the positional changes of the mechanical operation process in the vertical direction, thus improving the spatial fidelity.

[0059] Third, this application uses two screening steps: stress step determination and reduction in container volume. First, it extracts the initial full-load trajectory based on the combination of continuous stress step and whether the position falls into the container storage node. Then, it eliminates empty-running trajectories based on whether the container volume in the area traversed by the trajectory has actually decreased. This can effectively identify and filter out false operations such as intentional empty bucket lifting and false round trips in place, retaining only the valid full-load trajectory corresponding to the change in the physical space of the container, significantly improving the objectivity of operation trajectory traceability and the accuracy of supervision.

[0060] Fourth, this application imports the actual operation trajectory obtained by stitching together into the geographic information system according to the mechanical equipment identification for persistent solidification, which facilitates subsequent access, visualization and statistical analysis of the operation trajectory by equipment dimension and time dimension, and provides reliable data support for yard operation accounting, violation accountability, scheduling optimization and other business operations. Attached Figure Description

[0061] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0062] Figure 1 A flowchart illustrating the overall process of the GIS-based non-road mobile machinery operation trajectory tracing method provided in this application embodiment;

[0063] Figure 2 A schematic diagram illustrating the principle of synchronously generating a mechanical spatiotemporal trajectory from mechanical position data and lifting stress data provided in the embodiments of this application;

[0064] Figure 3 A schematic diagram of the spatial structure of the mechanical spatiotemporal trajectory projected onto the stockpile elevation model to generate the model mapping trajectory, provided in an embodiment of this application;

[0065] Figure 4 A schematic diagram illustrating the process of stress step section identification and initial full-load trajectory separation provided in the embodiments of this application;

[0066] Figure 5 A logical diagram illustrating how the initial full-load trajectory is segmented based on the volume reduction within a three-dimensional bounding box, as provided in this embodiment of the application.

[0067] Figure 6 This is a schematic diagram of the structure of a GIS-based non-road mobile machinery operation trajectory tracing system provided in an embodiment of this application. Detailed Implementation

[0068] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0069] Before providing a detailed description of the embodiments of this application, the following explanations are given for the purpose of understanding certain terms appearing in this document.

[0070] Non-road mobile machinery refers to engineering machinery used in non-public road areas such as port yards, mines, and construction sites. In this application embodiment, front-end cranes, empty container stackers, and gantry cranes in port container yards are typical examples, which are generally equipped with lifting components for grabbing or lifting containers.

[0071] Machine location data refers to a data sequence formed by the spatial geographic coordinates of the machine arranged in chronological order, which is continuously collected by a positioning module installed on non-road mobile machinery according to a fixed sampling period. The positioning module is, for example, a receiving terminal based on a global navigation satellite system, and the sampling period can be set from 1Hz to 10Hz. The specific sampling period can be set according to the actual operation accuracy requirements.

[0072] Lifting stress data refers to a data sequence formed by stress detection sensors arranged on the lifting components of non-road mobile machinery (such as boom hydraulic cylinders, lifting wire rope tension sensors, and lifting pin force sensors) according to a fixed sampling period, and the stress values ​​borne by the lifting components are arranged in chronological order.

[0073] A container yard elevation model is a three-dimensional digital model stored in a geographic information system that depicts the distribution characteristics of containers in the horizontal and vertical directions within a port container yard. Its underlying layer uses a basic grid coordinate system to regularly divide the yard space. Each grid cell records stacking attribute information such as whether a container is currently stacked at that location, the number of stacking layers, and the container type.

[0074] A container storage node refers to a grid node in the yard elevation model that records the container stacking attributes, i.e., a discrete location where containers exist or have existed before.

[0075] like Figure 1 As shown in the figure, the GIS-based non-road mobile machinery operation trajectory tracing method provided in this application includes steps S1 to S5. Each step will be described in detail below with reference to the accompanying drawings.

[0076] Step S1: Obtain the mechanical position data collected by the positioning module on the non-road mobile machinery and the lifting stress data collected by the lifting assembly of the non-road mobile machinery; extract the acquisition time corresponding to the mechanical position data and the lifting stress data; synchronize the mechanical position data and the lifting stress data according to the acquisition time; and generate the mechanical spatiotemporal trajectory.

[0077] Specifically, the machine position data is collected by a GNSS positioning module installed on the top of the off-road mobile machinery or outside the driver's cab. Each position point records longitude, latitude, elevation, and the corresponding positioning timestamp. The lifting stress data is collected by stress detection sensors arranged on the lifting assembly structure. Each stress point records the stress value and the corresponding stress timestamp. Considering that the sampling frequencies of the positioning module and the stress detection sensor may be inconsistent (for example, the GNSS sampling frequency is 1Hz, while the stress detection sensor sampling frequency can reach 50Hz or 100Hz), time synchronization processing is required to form a one-to-one spatiotemporal trajectory between the two.

[0078] like Figure 2 As shown, the synchronization process between mechanical position data and lifting stress data includes the following sub-steps.

[0079] Sub-step S11 involves extracting the positioning timestamp of the mechanical position data and the stress timestamp of the lifting stress data. Specifically, the data acquisition terminal can stamp the two types of data according to a unified standard time (e.g., UTC time), and the accuracy of both the positioning timestamp and the stress timestamp can reach the millisecond level.

[0080] Sub-step S12 establishes the positioning timestamp as the synchronization time reference axis. Since mechanical operation trajectory tracing focuses on the evolution of spatial coordinates over time, using the positioning timestamp as the synchronization time reference axis ensures the continuity of the subsequently generated spatiotemporal trajectory in the spatial dimension.

[0081] Sub-step S13 involves filling in the lifting stress data according to the time flow nodes on the synchronous time reference axis, ensuring that the time node density of the lifting stress data matches that of the mechanical position data. In cases of inconsistent sampling frequencies, node filling can be performed in one of the following ways: when the lifting stress data sampling frequency is higher than the positioning timestamp sampling frequency, the average or median of multiple stress points falling within the same positioning timestamp neighborhood is taken as the stress value at that time node; when the lifting stress data sampling frequency is lower than the positioning timestamp sampling frequency, linear interpolation is used between two adjacent stress points to fill in the missing stress value at the node, for example, for a stress point located at the stress timestamp... (Stress value) ) and the force timestamp (Stress value) A location timestamp between ) ( < < The corresponding stress value F can be calculated using the linear interpolation formula. The calculation yielded the result. The specific compensation method can be set according to the actual sampling frequency differences.

[0082] Sub-step S14 involves combining and binding the mechanical position data and the lifting stress data at the same time node on the synchronous time reference axis to generate a three-dimensional spatial node with stress values. The data structure of each three-dimensional spatial node includes, for example, a positioning timestamp, longitude, latitude, elevation, and the stress value at that moment.

[0083] Sub-step S15 connects all the three-dimensional spatial nodes with force values ​​according to the time sequence of the synchronous time reference axis to generate the mechanical spatiotemporal trajectory. Compared with a simple position trajectory, the mechanical spatiotemporal trajectory has an additional lifting stress dimension, so that each trajectory segment not only contains information about where the machine is going, but also contains physical information about whether the lifting component is currently bearing external cargo load, providing a key basis for subsequent trajectory segmentation.

[0084] Step S2: Retrieve the yard elevation model that records the distribution of containers in the port container transfer yard from the geographic information system, and project the mechanical spatiotemporal trajectory onto the yard elevation model according to the spatial coordinates to generate the model mapping trajectory.

[0085] The spatiotemporal trajectory of the machinery generated in step S1 is a geometric sequence using latitude, longitude, and elevation as spatial coordinates, and does not contain topological information about the physical space of containers within the yard. In order to have a spatial reference for subsequent determinations such as whether the machinery has passed through container storage nodes or whether the volume occupied by the container has changed, the spatiotemporal trajectory of the machinery needs to be projected onto the yard elevation model that can describe the distribution of container entities, so that the trajectory is correlated with the stacking state of the containers within the yard.

[0086] like Figure 3 As shown, the process of generating the model mapping trajectory includes the following sub-steps.

[0087] Sub-step S21 involves analyzing the basic grid coordinate system of the yard elevation model. The yard elevation model uses a regular three-dimensional raster structure to divide the yard space. For example, the side length of the grid unit is set based on the dimensions of a single standard container (e.g., 12.192 meters long, 2.438 meters wide, and 2.591 meters high), ensuring that each three-dimensional grid unit can accommodate an integer number of standard containers, facilitating subsequent calculations of the container's volume. The basic grid coordinate system uses a fixed reference corner point of the yard as its origin, and establishes three mutually orthogonal coordinate axes along the east, north, and vertical directions.

[0088] Sub-step S22 converts the spatial coordinates of the mechanical spatiotemporal trajectory into grid node coordinates in the basic grid coordinate system. Specifically, map projection methods such as Universal Transverse Mercator (UTM) can be used to convert latitude and longitude coordinates into Cartesian coordinates in meters, and then combine them with elevation values ​​to convert them into (X, Y, Z) coordinates in the basic grid coordinate system.

[0089] Sub-step S23 involves searching the yard elevation model for the three-dimensional grid cells into which the coordinates of the grid nodes fall. "Penetration" refers to the three-dimensional spatial nodes on the mechanical spatiotemporal trajectory falling into or passing through the three-dimensional grid cells in the yard elevation model. In actual calculations, spatial indexes (such as octrees or R-trees) can be used to accelerate the search efficiency to handle high-frequency queries in large-scale yard scenarios.

[0090] Sub-step S24 involves nesting and fitting the mechanical spatiotemporal trajectory along its movement path onto the surface spatial contour of the three-dimensional grid unit, outputting a model mapping trajectory embedded with the spatial topological distribution characteristics of the container. Nesting and fitting means that when the mechanical spatiotemporal trajectory passes over a three-dimensional grid unit with a stacked container, the elevation of that trajectory segment is corrected to the height corresponding to the top surface of that grid unit, thus ensuring the trajectory matches the actual contact contour of the container's top surface. When the mechanical spatiotemporal trajectory passes over a three-dimensional grid unit without a stacked container, the trajectory elevation is recorded according to the machine's own operating height. The final generated model mapping trajectory retains the shape of the machine's operating trajectory and corresponds one-to-one with the elevation fluctuations formed by the actual stacking of containers in the yard, laying the foundation for subsequent steps to identify whether the machine has performed container handling actions at container storage nodes.

[0091] Step S3: Read the synchronous lifting stress data along the model mapping trajectory. When the lifting stress data experiences continuous step changes and the spatial coordinates are located at the container storage node of the yard elevation model, separate the model mapping trajectory and extract the initial full-load trajectory of the lifting component under force.

[0092] The model mapping trajectory obtained in step S2 includes both the unloaded mechanical movement segment and the fully loaded mechanical flow segment, and the latter needs to be separated. In this embodiment, the inventors observed that when the machinery changes from an unloaded state to a fully loaded state, the stress borne by the lifting assembly undergoes a physical change from the baseline level to the load-bearing level, and this change inevitably occurs at the container storage node in the yard where containers are already stacked. Based on this pattern, a method combining stress step and container storage node location is proposed to extract the initial fully loaded trajectory.

[0093] like Figure 4 As shown, the process of extracting the initial full-load trajectory includes the following sub-steps.

[0094] Sub-step S31: Read the synchronized lifting stress data point by point along the path of the model mapping trajectory.

[0095] Sub-step S32 involves detecting the trend of stress value changes between adjacent reading points and marking the segments in the lifting stress data that meet the first preset condition as stress step segments. The so-called first preset condition is a condition used to determine whether a continuous physical jump caused by actual external cargo load has occurred in the lifting stress data, and its specific setting method will be explained in detail below.

[0096] Sub-step S33 involves extracting the starting coordinates of the stress step section and determining whether the starting coordinates fall within the range of container storage nodes recorded in the yard elevation model that have container stacking attributes. Specifically, this can be achieved by spatially intersecting the starting coordinates with the occupied volumes of all container storage nodes recorded in the yard elevation model. This determination step is introduced because relying solely on stress step may mistakenly classify situations such as machinery passing over potholes or lifting component vibrations as full load. Requiring the step starting point to be located at a container storage node further ensures that the stress step is indeed caused by grabbing a container, thereby improving the accuracy of the determination.

[0097] In sub-step S34, if the location falls within the container storage node range that records container stacking attributes, the starting point of the stress step segment is taken as the separation start point, and the physical inflection point where the lifting stress data changes from a stable state to a decreasing state is taken as the separation end point. If a stress step is detected but the location does not fall within the container storage node, the fluctuation is determined to be a non-operational disturbance (such as road bumps), and the system does not perform trajectory separation. Instead, it continues to execute step S31 to read data along the trajectory until a matching operation node is found. The so-called physical inflection point refers to the turning point where the stress value begins to continuously decrease from a nearly stable load level when the lifting component transitions from a loaded state to an unloaded state, corresponding to the moment when the machinery lowers the container.

[0098] Sub-step S35: Extract the model mapping trajectory segment between the separation start end and the separation end as the initial full-load trajectory. This initial full-load trajectory completely covers the entire movement process of the machine from grabbing the container to placing it down.

[0099] Furthermore, the specific identification method for the stress step segment in sub-step S32 includes the following sub-steps:

[0100] Sub-step S321 involves dividing the lifting stress data into a moving observation window that slides at a fixed step size. The window width and sliding step size of the moving observation window can be set according to the sampling frequency of the lifting stress data and the typical operating rhythm. For example, the window width can be set to 3 to 10 seconds and the sliding step size can be set to 1 second. The specific settings can be made according to actual needs.

[0101] Sub-step S322: Count the number of peak nodes where stress values ​​increase within the moving observation window. A peak node refers to a stress data point that exhibits a local maximum value relative to its preceding and following adjacent reading points.

[0102] Sub-step S323 involves summing the stress increase difference between two adjacent wave crest nodes to obtain the cumulative stress increment. This cumulative stress increment reflects the magnitude of the overall stress increase within the observation window.

[0103] Sub-step S324 involves considering the inherent stress fluctuation amplitude caused by the gravity of the lifting assembly's own physical structure. When the cumulative stress increment exhibits a physical abrupt increase exceeding the inherent stress fluctuation amplitude, it is determined that an actual external cargo load has occurred. The inherent stress fluctuation amplitude refers to the range of stress fluctuations caused by factors such as hydraulic system vibration, mechanical vibration, and sensor noise when the lifting assembly is not gripping any external object and is only bearing its own weight. An upper limit can be obtained through statistical calibration under no-load conditions, for example, three times the standard deviation of stress fluctuations under no-load conditions can be taken as this upper limit.

[0104] Sub-step S325 identifies the segment of the moving observation window where the actual external cargo load is generated and the subsequent stress value fluctuation remains within a fixed stable range as the stress step segment. The fixed stable range refers to the range where the stress value fluctuates around the load level without exceeding a certain threshold (e.g., within 5% of the load level). The specific threshold can be set according to actual needs. The fact that the subsequent stress value remains within the fixed stable range indicates that the container has been successfully grabbed and stably lifted, rather than experiencing a brief shaking followed by a fall, further ensuring the reliability of the stress step determination.

[0105] Step S4: Calculate the volume occupied by the container in the area traversed by the initial full-load trajectory in the yard elevation model. According to the volume reduction of the container volume occupied during the corresponding time period of the initial full-load trajectory, divide the initial full-load trajectory, eliminate idling movement trajectories that do not cause changes in the physical space, and retain the effective full-load trajectory.

[0106] The initial full-load trajectory extracted in step S3 was only screened based on lifting stress, and the following situations may still exist: Although the machinery grabbed and lifted the container, due to the operator's deliberate spurious operation (such as grabbing and then putting it back in place, or repeatedly lifting and lowering it in a short period of time), it did not actually cause a real change in the spatial distribution of the containers in the yard. In order to further eliminate this type of trajectory segment that does not produce an actual flow effect, this step compares the volume change of the stacked containers in the area traversed by the initial full-load trajectory to determine whether it has caused an actual displacement of the container space.

[0107] like Figure 5 As shown, the process of obtaining the effective full-load trajectory includes the following sub-steps.

[0108] Sub-step S41 involves defining a three-dimensional bounding box in the yard elevation model that covers the initial fully loaded trajectory. Specifically, the (X, Y, Z) coordinates of all nodes on the initial fully loaded trajectory are traversed, and the minimum and maximum values ​​in the X, Y, and Z directions are calculated respectively. These six extreme values ​​are used to form a cuboid as the three-dimensional bounding box. This three-dimensional bounding box covers all the three-dimensional mesh cells traversed by the initial fully loaded trajectory.

[0109] Sub-step S42: At the start of the time period corresponding to the initial full-load trajectory, read the initial occupied volume of the solid stacks inside the spatial three-dimensional bounding box. The preset time period is the time period corresponding to the time span of the initial full-load trajectory. The initial occupied volume refers to the total volume of containers already stacked in all three-dimensional grid cells covered by the spatial three-dimensional bounding box at the start of this time period, which can be obtained by accumulating the stacking attributes of each three-dimensional grid cell in the yard elevation model.

[0110] Sub-step S43: At the end of the time period corresponding to the initial full-load trajectory, read the final occupied volume of the stacked entities inside the three-dimensional bounding box. The reading method is the same as sub-step S42, only the time node changes from the start time to the end time.

[0111] Sub-step S44: Subtract the final occupied volume from the initial occupied volume to obtain the volume reduction of the container's occupied volume. This volume reduction reflects the total volume of containers moved from this spatial area within the time period corresponding to the initial full-load trajectory.

[0112] In sub-step S45, when the volume reduction meets the second preset condition, the corresponding segment is determined to be the idling movement trajectory and spatially cut off, retaining the remaining valid segments as valid full-load trajectories. The second preset condition is used to determine whether the initial full-load trajectory segment has not actually caused a change in the container space. For example, it can be set as follows: if the volume reduction is less than a preset percentage (e.g., 10%) of the volume of a standard container, it is considered that there is basically no actual handling, and the segment is determined to be an idling movement trajectory; the specific threshold can be set according to the actual operational accuracy requirements. The remaining segments that meet the requirement of a volume reduction exceeding this percentage are retained as valid full-load trajectories.

[0113] Step S5: Connect all valid full-load trajectories according to the order of collection time, combine them into the actual operation trajectory of container flow, and import the actual operation trajectory into the geographic information system for storage.

[0114] The effective full-load trajectories obtained after the two screening steps S3 and S4 are several discrete trajectory segments, each corresponding to a single container transfer. In actual supervision and statistical analysis, it is often necessary to view the entire operation trajectory from the perspective of mechanical equipment. This step involves piecing together these discrete segments according to mechanical identification and time sequence into a complete and accurate operation trajectory.

[0115] Specifically, step S5 includes the following sub-steps.

[0116] Sub-step S51 involves filtering out a set of trajectories belonging to the same non-road mobile machinery equipment identifier from all valid fully loaded trajectories. The equipment identifier is, for example, the equipment number of the machinery or the hardware serial number of the positioning module. Each valid fully loaded trajectory is associated with and recorded with the equipment identifier of the machinery it belongs to when it is generated.

[0117] Sub-step S52: Read the acquisition time bound to the start and end endpoints of each valid full-load trajectory in the trajectory set.

[0118] Sub-step S53: Arrange the valid fully loaded trajectories belonging to the same non-road mobile machinery equipment identifier in a timeline according to the order of the collection time.

[0119] Sub-step S54 involves using spatial lines to connect the termination endpoint of the first-ordered valid full-load trajectory to the starting endpoint of the second-ordered valid full-load trajectory, thus assembling the actual operation trajectory. The spatial lines can be simple straight lines, or they can be filled in using actual path backfilling based on the unloaded movement data between adjacent full-load sections of the machinery. This embodiment does not limit the specific path.

[0120] Sub-step S55 records the non-road mobile machinery equipment identifier corresponding to the actual operation trajectory and imports it into the traceability database of the geographic information system for persistent storage. The stored actual operation trajectory can be visualized and statistically queried in the geographic information system according to the equipment dimension and time dimension, thereby supporting business functions such as operation accounting, violation accountability, and scheduling optimization.

[0121] Based on the above method, this application also provides a GIS-based non-road mobile machinery operation trajectory tracing system, such as... Figure 6 As shown, the system includes an acquisition module, a model mapping module, a separation module, a calculation module, and a connection module.

[0122] The acquisition module is used to acquire mechanical position data collected by the positioning module on the non-road mobile machinery and lifting stress data collected by the lifting assembly of the non-road mobile machinery, extract the acquisition time corresponding to the mechanical position data and the lifting stress data, synchronize the mechanical position data and the lifting stress data according to the acquisition time, and generate the mechanical spatiotemporal trajectory. This module corresponds to the function performed in step S1 and its sub-steps above.

[0123] The model mapping module is used to retrieve the yard elevation model that records the distribution of containers in the port container transfer yard from the geographic information system, and project the mechanical spatiotemporal trajectory onto the yard elevation model according to spatial coordinates to generate a model mapping trajectory. This module corresponds to the function performed in step S2 and its sub-steps above.

[0124] The separation module is used to read synchronous lifting stress data along the model mapping trajectory. When the lifting stress data experiences continuous step changes and the spatial coordinates are located at the container storage node of the yard elevation model, the model mapping trajectory is separated to extract the initial full-load trajectory of the lifting assembly under stress. This module corresponds to the function performed in step S3 and its sub-steps above.

[0125] The calculation module is used to calculate the volume occupied by the container in the area traversed by the initial full-load trajectory in the yard elevation model. Based on the volume reduction of the container's occupied volume within the corresponding time period of the initial full-load trajectory, the initial full-load trajectory is segmented, idling trajectories that do not cause changes in physical space are discarded, and valid full-load trajectories are retained. This module corresponds to the function performed in step S4 and its sub-steps described above.

[0126] The connection module is used to connect all valid full-load trajectories in chronological order of data collection, combine them into a real operational trajectory for container flow, and import the real operational trajectory into the geographic information system for storage. This module corresponds to the function performed in step S5 and its sub-steps above.

[0127] This application also provides a computing device, including a processing component and a storage component. The processing component can be a general-purpose processor, such as a central processing unit (CPU), digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), or other devices with data processing capabilities, or a combination thereof. The storage component can be a non-volatile memory, such as a hard disk, solid-state drive, or flash memory. The storage component stores one or more computer instructions, which are invoked and executed by the processing component to implement the GIS-based non-road mobile machinery operation trajectory tracing method described in any of the above embodiments.

[0128] This application also provides a computer storage medium storing a computer program. When the computer program is executed by a computer, it implements the GIS-based non-road mobile machinery operation trajectory tracing method described in any of the above embodiments. The computer storage medium includes, but is not limited to, optical discs, USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), etc.

[0129] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A GIS-based method for tracing the operational trajectory of non-road mobile machinery, characterized in that, include: The machine position data collected by the positioning module on the non-road mobile machinery and the lifting stress data collected by the lifting assembly of the non-road mobile machinery are obtained. The acquisition time corresponding to the machine position data and the lifting stress data is extracted. The machine position data and the lifting stress data are synchronized according to the acquisition time to generate the machine spatiotemporal trajectory. Retrieve the container yard elevation model that records the distribution of containers in the port container transfer yard from the geographic information system, and project the mechanical spatiotemporal trajectory onto the container yard elevation model according to spatial coordinates to generate the model mapping trajectory. Read the synchronous lifting stress data along the model mapping trajectory. When the lifting stress data makes a continuous step and the spatial coordinate is located at the container storage node of the yard elevation model, separate the model mapping trajectory and extract the initial full-load trajectory of the lifting component under force. Calculate the volume occupied by the container in the area traversed by the initial full-load trajectory in the yard elevation model. According to the volume reduction of the container's occupied volume within the corresponding time period of the initial full-load trajectory, divide the initial full-load trajectory, eliminate idling movement trajectories that do not cause changes in the physical space, and retain the effective full-load trajectory. All valid full-load trajectories are connected in chronological order of collection time, and combined to form the actual operation trajectory of container flow. The actual operation trajectory is then imported into the geographic information system for storage.

2. The method according to claim 1, characterized in that, Synchronize the mechanical position data and the lifting stress data according to the acquisition time to generate the mechanical spatiotemporal trajectory, including: Extract the positioning timestamp of the mechanical position data and the force timestamp of the lifting stress data; The positioning timestamp is established as the synchronization time reference axis; According to the time flow nodes on the synchronous time reference axis, the lifting stress data is filled with nodes so that the time node density of the lifting stress data is consistent with the mechanical position data. The mechanical position data and the lifting stress data at the same time node on the synchronous time reference axis are combined and bound to generate a three-dimensional spatial node with force values. All three-dimensional spatial nodes with force values ​​are connected according to the time sequence of the synchronous time reference axis to generate a mechanical spatiotemporal trajectory.

3. The method according to claim 1, characterized in that, The mechanical spatiotemporal trajectory is projected onto the stockpile elevation model according to spatial coordinates to generate a model mapping trajectory, including: The basic grid coordinate system of the aforementioned stockpile elevation model is analyzed; The spatial coordinates of the mechanical spatiotemporal trajectory are converted into grid node coordinates under the basic grid coordinate system; Search the three-dimensional grid cell into which the coordinates of the grid node fall in the stockyard elevation model; Following the movement of the mechanical spatiotemporal trajectory, the mechanical spatiotemporal trajectory is nested and fitted onto the surface spatial contour of the three-dimensional mesh unit to output a model mapping trajectory with embedded container spatial topological distribution features.

4. The method according to claim 1, characterized in that, Read synchronized lifting stress data along the model mapping trajectory. When the lifting stress data experiences continuous step changes and the spatial coordinates are located at the container storage node of the yard elevation model, separate the model mapping trajectory and extract the initial full-load trajectory of the lifting assembly under stress, including: The synchronized lifting stress data is read point by point along the path of the model mapping trajectory; The trend of stress value change between adjacent reading points is detected, and the segment in the lifting stress data that meets the first preset condition is marked as the stress step segment; Extract the starting coordinates of the stress step section and determine whether the starting coordinates fall within the range of the container storage node that records the container stacking attributes in the yard elevation model. If it falls within the container storage node range that records container stacking attributes, the starting point of the stress step section is taken as the separation start point, and the physical inflection point where the lifting stress data changes from a stable state to a decreasing state is taken as the separation end point. If the container does not fall within the range of the container storage node that records the container stacking attributes, it is determined to be an invalid stress fluctuation, and the process returns to the step of reading the synchronized lifting stress data point by point along the path of the model mapping trajectory. Extract the model mapping trajectory segment between the separation start end and the separation end end as the initial full-load trajectory.

5. The method according to claim 4, characterized in that, The stress value change trend between adjacent reading points is detected, and the segment in the lifting stress data that meets the first preset condition is marked as the stress step segment, including: The lifting stress data is divided into moving observation windows that slide at fixed step sizes; The number of peak nodes showing an increase in stress value within the moving observation window is counted. The cumulative stress increment is obtained by summing the stress increase difference between two adjacent wave crest nodes; Based on the inherent force fluctuation amplitude generated by the gravity of the lifting assembly's own physical structure, when the cumulative force increment exhibits a physical abrupt increase exceeding the inherent force fluctuation amplitude, it is determined that an actual external cargo load has been generated. The segment containing the moving observation window that generates actual external cargo load and whose subsequent stress value fluctuations remain within a fixed and stable range is identified as the stress step zone.

6. The method according to claim 1, characterized in that, Calculate the volume occupied by the container in the area traversed by the initial full-load trajectory in the yard elevation model. Based on the volume reduction of the container's occupied volume within the corresponding time period of the initial full-load trajectory, segment the initial full-load trajectory, discarding idling trajectories that do not cause changes in physical space, and retaining valid full-load trajectories, including: In the stockyard elevation model, delineate a three-dimensional bounding box that covers the initial full-load trajectory. At the start of the time period corresponding to the initial full-load trajectory, the initial occupied volume of the entity stack inside the three-dimensional bounding box of space is read. At the end of the time period corresponding to the initial full-load trajectory, the final occupied volume of the stacked entities inside the three-dimensional bounding box of the space is read. Subtracting the final occupied volume from the initial occupied volume yields the reduction in the volume occupied by the box. When the volume reduction meets the second preset condition, the corresponding segment is determined to be the idling movement trajectory and spatial cut-off is performed, while the remaining effective segment is retained as the effective full-load trajectory.

7. The method according to claim 1, characterized in that, All valid full-load trajectories are connected in chronological order of collection time, and combined to form the actual operational trajectory of container flow. This actual operational trajectory is then imported into a geographic information system for storage, including: From all valid fully loaded trajectories, identify the set of trajectories belonging to the same non-road mobile machinery equipment identifier; Read the acquisition time bound to the start and end endpoints of each valid full-load trajectory in the trajectory set; According to the rule of collecting data in chronological order, the valid fully loaded trajectories belonging to the same non-road mobile machinery equipment are arranged in timeline; Spatial lines are used to connect the terminating endpoint of the first-ordered valid full-load trajectory to the starting endpoint of the second-ordered valid full-load trajectory, thus piecing together the actual operation trajectory. Record the identification of the non-road mobile machinery equipment corresponding to the actual operation trajectory and import it into the traceability database of the geographic information system for persistent storage.

8. A GIS-based system for tracing the operational trajectory of non-road mobile machinery, characterized in that, include: The acquisition module is used to acquire the mechanical position data collected by the positioning module on the non-road mobile machinery and the lifting stress data collected by the lifting assembly of the non-road mobile machinery, extract the acquisition time corresponding to the mechanical position data and the lifting stress data, synchronize the mechanical position data and the lifting stress data according to the acquisition time, and generate the mechanical spatiotemporal trajectory. The model mapping module is used to retrieve the yard elevation model that records the distribution of containers in the port container transfer yard in the geographic information system, and project the mechanical spatiotemporal trajectory into the yard elevation model according to the spatial coordinates to generate the model mapping trajectory. The separation module is used to read synchronous lifting stress data along the model mapping trajectory. When the lifting stress data experiences continuous step changes and the spatial coordinates are located at the container storage node of the yard elevation model, the model mapping trajectory is separated to extract the initial full-load trajectory of the lifting component under force. The calculation module is used to calculate the volume occupied by the container in the area through which the initial full-load trajectory passes in the yard elevation model. According to the volume reduction of the container volume occupied during the corresponding time period of the initial full-load trajectory, the initial full-load trajectory is divided, and the idle movement trajectory that does not cause changes in the physical space is eliminated, and the effective full-load trajectory is retained. The connection module is used to connect all valid full-load trajectories in chronological order of collection time, combine them into the actual operation trajectory of container flow, and import the actual operation trajectory into the geographic information system for storage.

9. A computing device, characterized in that, It includes a processing component and a storage component; the storage component stores one or more computer instructions; the one or more computer instructions are invoked and executed by the processing component to implement the GIS-based non-road mobile machinery operation trajectory tracing method as described in any one of claims 1 to 7.

10. A computer storage medium, characterized in that, The system contains a computer program that, when executed by a computer, implements a GIS-based method for tracing the operation trajectory of non-road mobile machinery as described in any one of claims 1 to 7.

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