Linear cultural heritage data collection method and apparatus based on unmanned aerial vehicle remote sensing

Abstract

Disclosed in the present invention are a linear cultural heritage data collection method and apparatus based on unmanned aerial vehicle remote sensing. The method comprises: establishing digital twin precision systems; determining, on a satellite map, measurement ranges for different measurement objects of cultural heritages; determining data collection parameters of an unmanned aerial vehicle remote sensing device combination for each measurement object; determining a flight height on the basis of the minimum ground resolution corresponding to each measurement object and the data collection parameters; performing flight task planning on each measurement object to obtain a task planning result; obtaining image data collected by the unmanned aerial vehicle remote sensing device combination, and processing the image data to generate a two-dimensional digital result and a three-dimensional digital result, wherein the image data is obtained by means of the unmanned aerial vehicle remote sensing device combination performing data collection on linear cultural heritages according to the data collection parameters, the flight height and the task planning result; and constructing digital twin models with different levels of precision and forming a linear cultural heritage digital twin. The present invention can achieve high data collection efficiency and high data quality.

Description

Linear cultural heritage data collection method and device based on UAV remote sensing

[0001] This application claims priority to Chinese patent application No. 202410028591.7 filed on January 8, 2024, entitled “Linear cultural heritage data collection method and device based on UAV remote sensing”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the field of cultural heritage protection data collection and modeling technology, and in particular to a linear cultural heritage data collection method and device based on unmanned aerial vehicle remote sensing. Background Art

[0003] This section is intended to provide a background or context to the embodiments of the invention that are recited in the claims. No statement herein is admitted to be prior art by virtue of its inclusion in this section.

[0004] As the cost of drone manufacturing and use decreases and their technical performance improves, civilian drones are becoming increasingly popular, and the use of drones for remote sensing research on cultural heritage is gaining increasing attention. Different types of drones (fixed-wing, rotary-wing, etc.) can carry different types of sensors (visible light, multispectral, infrared, LiDAR, etc.), enabling diverse explorations of cultural heritage sites across diverse regions, eras, and categories.

[0005] Compared to satellite, manned, and ground-based remote sensing, drone remote sensing offers unique advantages for cultural heritage preservation and scientific research: minimal environmental impact, greater operational flexibility, and high-quality data. First, compared to satellites and manned aircraft, drones operate at lower altitudes, avoiding issues such as loss of remote sensing data caused by clouds and fog. Furthermore, drones can operate even in hazardous environments, winds below force 8, and light rain, making them relatively immune to environmental impact. Second, satellite and manned aircraft remote sensing operations lack maneuverability, are limited in operating angles, and inevitably face obstruction from terrain. These issues are mitigated by drone remote sensing. Furthermore, compared to the narrow field of view and complex, tedious workflows inherent to ground-based remote sensing, drone remote sensing offers exceptional operational flexibility, allowing for flexible acquisition of diverse data types from varying altitudes and angles through a combination of planned and manual flights. Finally, since drone remote sensing can reach locations that are difficult for human beings to reach conveniently, promptly and contactlessly, and combined with close-up photogrammetry technology, it can obtain data with up to millimeter-level accuracy, this can be used to quickly, efficiently and non-destructively collect various types of high-quality data for cultural heritage sites such as the Great Wall located on cliffs, towering wooden pagodas, and the Hanging Temple that looks like a castle in the sky.

[0006] In recent years, with the advancement of drones and sensor equipment, as well as advances in computer science, the application of drone remote sensing in cultural heritage research has increased significantly. However, current drone remote sensing data collection often falls into a one-sided pursuit of scale and comprehensiveness, resulting in low data efficiency and high noise. Consequently, there is a lack of efficient and high-quality solutions for collecting cultural heritage data using drone remote sensing.

[0007] Summary of the Invention

[0008] The present invention provides a method for collecting linear cultural heritage data based on drone remote sensing, which is used to collect drone remote sensing data of cultural heritage based on the actual needs of engineering drawing. The method has high efficiency and high data quality. The method includes:

[0009] Establish a digital twin accuracy system for cultural heritage data collection, with each digital twin accuracy system used to represent engineering drawings of different scales and the corresponding minimum ground resolution;

[0010] Determine the measurement ranges of different measurement objects of cultural heritage on satellite images based on the digital twin accuracy system;

[0011] Determine the data collection parameters of the UAV remote sensing equipment combination for each measurement object;

[0012] Determining the flight altitude based on the minimum ground resolution corresponding to each measurement object and the data acquisition parameters;

[0013] According to the measurement range of each measurement object, flight mission planning is performed for each measurement object to obtain mission planning results;

[0014] Obtaining image data collected by the UAV remote sensing device assembly, processing the image data, and generating a two-dimensional digital product and a three-dimensional digital product, wherein the image data is obtained by the UAV remote sensing device assembly through data collection of the linear cultural heritage according to the data collection parameters, the flight altitude, and the mission planning results;

[0015] Based on two-dimensional and three-dimensional digital results, digital twin models of different precisions are constructed to form a linear cultural heritage digital twin.

[0016] The present invention also provides a linear cultural heritage data collection device based on drone remote sensing, which is used to collect cultural heritage remote sensing data based on the actual needs of engineering drawing. The device has high efficiency and high data quality. The device includes:

[0017] A digital twin precision system establishment module is used to establish a digital twin precision system for cultural heritage data collection. Each digital twin precision system is used to represent engineering drawings of different scales and the corresponding minimum ground resolution.

[0018] a measurement range determination module, configured to determine the measurement ranges of different measurement objects of the cultural heritage on a satellite image based on the digital twin accuracy system;

[0019] A data acquisition parameter determination module, used to determine the data acquisition parameters of the UAV remote sensing equipment combination for each measurement object;

[0020] A flight altitude determination module, configured to determine the flight altitude based on the minimum ground resolution corresponding to each measurement object and the data acquisition parameters;

[0021] A flight mission planning module is used to plan a flight mission for each measurement object according to the measurement range of each measurement object and obtain a mission planning result;

[0022] An image data acquisition and processing module is used to obtain image data collected by the UAV remote sensing device combination, process the image data, and generate two-dimensional digital products and three-dimensional digital products, wherein the image data is obtained by the UAV remote sensing device combination through data collection of linear cultural heritage according to the data collection parameters, the flight altitude, and the mission planning results;

[0023] The linear cultural heritage digital twin construction module is used to construct digital twin models of different accuracies based on two-dimensional digital achievements and three-dimensional digital achievements, and form a linear cultural heritage digital twin.

[0024] An embodiment of the present invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the above-mentioned linear cultural heritage data collection method based on drone remote sensing is implemented.

[0025] An embodiment of the present invention also provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the above-mentioned linear cultural heritage data collection method based on drone remote sensing.

[0026] An embodiment of the present invention further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, it implements the above-mentioned linear cultural heritage data collection method based on drone remote sensing.

[0027] In an embodiment of the present invention, a digital twin precision system for cultural heritage data collection is established, and each digital twin precision system is used to represent engineering drawings of different scales and the corresponding minimum ground resolution; according to the digital twin precision system, the measurement range of different measurement objects of the cultural heritage is determined on the satellite map; the data collection parameters of the drone remote sensing equipment combination for each measurement object are determined; according to the minimum ground resolution corresponding to each measurement object and the data collection parameters, the flight altitude is determined; according to the measurement range of each measurement object, a flight mission is planned for each measurement object to obtain a mission planning result; the image data collected by the drone remote sensing equipment combination is obtained, and the image data is processed to generate a two-dimensional digital product and a three-dimensional digital product, wherein the image data is obtained by the drone remote sensing equipment combination by collecting data on the linear cultural heritage according to the data collection parameters, the flight altitude and the mission planning result; according to the two-dimensional digital product and the three-dimensional digital product, digital twin models of different precisions are constructed to form a digital twin of the linear cultural heritage. Through the above steps, the solution proposed in the embodiment of the present invention can perform measurement range analysis and flight mission planning for different measurement objects, thereby realizing accurate and efficient acquisition of image data. After subsequent processing of the image data, a linear cultural heritage digital twin is formed, providing a comprehensive and effective solution for the digital protection and exhibition of cultural heritage, and providing scientific, effective and timely input support for the cultural heritage digital twin. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0029] FIG1 is a flow chart of a method for collecting linear cultural heritage data based on UAV remote sensing according to an embodiment of the present invention;

[0030] FIG2 is a schematic diagram of linear cultural heritage data collection based on UAV remote sensing in an embodiment of the present invention;

[0031] FIG3 is a schematic diagram of a linear object flight mission planning according to an embodiment of the present invention;

[0032] FIG4 is a schematic diagram of a linear cultural heritage data acquisition device based on UAV remote sensing according to an embodiment of the present invention;

[0033] FIG5 is a schematic diagram of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0034] FIG1 is a flow chart of a linear cultural heritage data collection method based on drone remote sensing according to an embodiment of the present invention. FIG2 is a schematic diagram of a linear cultural heritage data collection method based on drone remote sensing according to an embodiment of the present invention, including:

[0035] Step 101: Establish a digital twin accuracy system for cultural heritage data collection, where each digital twin accuracy system is used to represent engineering drawings of different scales and the corresponding minimum ground resolution.

[0036] Step 102: Determine the measurement range of different measurement objects of the cultural heritage on the satellite image based on the digital twin accuracy system;

[0037] Step 103, determining data acquisition parameters of the UAV remote sensing device combination for each measurement object;

[0038] Step 104, determining the flight altitude according to the minimum ground resolution corresponding to each measurement object and the data acquisition parameters;

[0039] Step 105: Perform flight mission planning for each measurement object according to the measurement range of each measurement object to obtain a mission planning result;

[0040] Step 106: Obtain image data collected by the UAV remote sensing device assembly, process the image data, and generate a two-dimensional digital product and a three-dimensional digital product. The image data is obtained by the UAV remote sensing device assembly by collecting data of the linear cultural heritage according to the data collection parameters, the flight altitude, and the mission planning results.

[0041] Step 107: construct digital twin models of different precisions based on the two-dimensional digital results and the three-dimensional digital results, and form a linear cultural heritage digital twin.

[0042] Through the above steps, the solution proposed in the embodiment of the present invention can perform measurement range analysis and flight mission planning for different measurement objects, thereby realizing accurate and efficient acquisition of image data. After subsequent processing of the image data, a linear cultural heritage digital twin is formed, providing a comprehensive and effective solution for the digital protection and exhibition of cultural heritage, and providing scientific, effective and timely input support for the cultural heritage digital twin.

[0043] Referring to Figures 1 and 2, the solution proposed in the embodiment of the present invention involves preliminary preparation, establishment of a digital twin precision system, equipment combination, task planning, field operations, indoor operations, and results export; of course, drone remote sensing operations require repeated work both indoors and outdoors.

[0044] Each step is described in detail below.

[0045] Preliminary Preparation: Currently, there's no unified standard for digital twin accuracy. This invention pre-defines a digital twin accuracy system for different scenarios based on the problems reflected and solved by engineering drawings at different scales. As shown in Figure 2, before commencing field work, extensive preliminary research is required. Crucially, this preliminary work requires clarifying the operational objectives. This means being problem-oriented and approaching field work with a clear goal in mind. This objective involves the accuracy requirements for measuring different ground objects. Because field work is subject to numerous objective constraints, such as time and conditions, this approach can prevent field work from falling into the trap of overly ambitious and comprehensive efforts, thereby greatly improving operational efficiency. Once the objectives are established, the UAV remote sensing system, including the flight platform, sensors, and ground control system, can be assembled. The appropriate combination can improve operational quality and avoid duplication of effort. Based on the determined UAV remote sensing equipment combination, a specific flight plan can be developed, and actual field and office work can then be carried out. After data processing is completed and the first batch of results are obtained, missed measurements or unsatisfactory data are often discovered. Therefore, it is necessary to go back and check whether the equipment combination is reasonable, whether the equipment needs to be updated or replaced, or to modify the flight mission based on the original drone remote sensing equipment combination. In this way, repeated iterations will eventually obtain an ideal set of digital results such as two-dimensional images and three-dimensional models.

[0046] During the preliminary preparation stage, it is also necessary to clarify the attributes of the measurement objects in the digital twin precision system, including but not limited to heritage type (ancient cultural sites, ancient tombs, ancient buildings, grottoes and temples, stone carvings, murals, important modern and contemporary historical sites and representative buildings), construction age (ancient, modern and contemporary), protection level (national, provincial, municipal, county, unclassified), building materials (earthen, stone, brick, mixed), risk type (rainwater erosion, wind erosion, agricultural cultivation, grazing, housing construction, soil erosion, afforestation, tomb robbing, freeze-thaw, water conservancy facilities, power facilities, salinization, tourism development, wall mold, special events, pollution, no need for tourism, improper display). These attributes are used for subsequent analysis.

[0047] In step 101, a digital twin accuracy system for cultural heritage data collection is established, where each digital twin accuracy system is used to represent engineering drawings of different scales and the corresponding minimum ground resolution;

[0048] In one embodiment, a digital twin accuracy system for cultural heritage data collection is established, including:

[0049] Determine the target scale system for digital twins of cultural heritage data collection. The target scale system includes the scale of the existing environment associated with general mapping, the scale of individual buildings associated with architectural mapping, and the scale of disease characteristics associated with detailed mapping. Among them, general mapping, architectural mapping, and detailed mapping are engineering drawings, and the scale of the existing environment, the scale of individual buildings, and the scale of disease characteristics are the target sizes of land features.

[0050] Determine the digital twin accuracy system corresponding to the digital twin target scale system. The digital twin accuracy system includes the scale of each engineering drawing and the corresponding minimum ground resolution. The minimum ground resolution is the accuracy of the ground object size that can be accurately resolved in the image data collected by the drone;

[0051] In the above embodiment, the associated environmental scale for general mapping targets buildings, structures, roads, rivers, and large trees; the scale for individual buildings associated with architectural mapping targets individual buildings and building components; and the scale for defect characteristics associated with detailed mapping targets building material units and defect characteristics. The minimum ground resolution should be sufficiently high to ensure that the characteristics and dimensions of the smallest ground object to be measured can be accurately distinguished.

[0052] For example, in the embodiment of the present invention, the scale of general drawing is 1:500, the scale of architectural drawing is 1:100, and the scale of detailed drawing is 1:1.

[0053] In one embodiment, determining a digital twin accuracy system corresponding to a target scale system of a digital twin includes:

[0054] Determine the scale for each type of engineering drawing;

[0055] The following formula is used to determine the minimum ground resolution for each engineering drawing based on its scale:

[0056] Among them, GSD is the minimum ground resolution, meters / pixel, A is the scale of engineering drawings, and B is the digital image accuracy, pixels / inch.

[0057] Let A be the scale ratio (for example, if the scale is 1:500, then A = 500), then 1 meter on the map represents A meters in reality. Usually, the minimum distance between two points that the human eye can distinguish is 1×10 -4 meter (0.1 mm), then the accuracy of a map drawn at a scale of 1:A is A×10 -4 Meters. Assume that the output digital image accuracy (DPI) is B pixels / inch. The conversion relationship is:

[0058] 1 inch = 0.0254 meters

[0059] digital imaging

[0060] For example, in the context of general mapping, the smallest feature reflected in a 1:500 scale drawing is approximately 0.0423 meters, using a 300dpi digital image accuracy as an example. This means the minimum ground resolution is 0.0423 meters. In the context of architectural mapping, the smallest feature, such as doors, windows, and steps, is considered. Using a 300dpi digital image accuracy as an example, the smallest feature reflected in a 1:100 scale drawing is approximately 0.00847 meters, using a 300dpi digital image accuracy as an example. This means the minimum ground resolution is 0.00847 meters. In the context of detailed mapping, the smallest feature, such as building material units (bricks, stones, and wood), feature defects (such as cracks), and construction year are considered. Using a 300dpi digital image output accuracy as an example, the smallest feature reflected in a 1:1 scale drawing is approximately 0.0000847 meters, using a 1:1 scale drawing as an example. This means the minimum ground resolution is 0.0000847 meters.

[0061] In one embodiment, step 102 (determining the measurement ranges of different measurement objects of the cultural heritage on the satellite image based on the digital twin accuracy system) includes:

[0062] When the measurement object is a planar object, on the satellite image, the linear cultural heritage body is described as multiple continuous straight line segments, with the inflection points of the curvature change of the linear cultural heritage body as the connection points. The linear cultural heritage body is then extended in both directions by a first preset length to generate the measurement range of the planar object. The planar object is all land features involved in the overall map mapping and associated endowment environment scale. The first preset length is determined based on the protection level of the measurement object. For example, if the protection level is national, the first preset length is 500 meters.

[0063] When the measurement object is a linear object, on a satellite image, the linear cultural heritage body is described as a polyline composed of continuous straight lines, with the curvature turning points of the linear cultural heritage body as breakpoints. The polyline is used as a track, and the cross-section width of the linear cultural heritage body at each breakpoint plus a second preset length is used as the cross-section to generate the measurement range of the linear object. The linear object is all ground objects involved in the scale of the building unit associated with the architectural drawing, and the polyline is the centerline of the linear measurement area.

[0064] When the measurement object is a point object, on the satellite image, the corner points of a single independent point object are connected and extended outward by a third preset length to generate the measurement range of the point object. The point object is all the ground objects involved in the detailed mapping associated disease characteristic scale.

[0065] During specific implementation, the second preset length and the third preset length may be the same.

[0066] In step 103, data acquisition parameters for the drone remote sensing device assembly for each measurement object are determined. In one embodiment, the drone remote sensing device assembly includes a drone gimbal and a sensor. The data acquisition parameters include the sensor's focal length, the width of the sensor-captured image, the height and width of the sensor-captured image, and the rotation angle of the drone gimbal. The rotation angle of the drone gimbal is generally 0°-90°.

[0067] In one embodiment, step 104 (determining the flight altitude based on the minimum ground resolution corresponding to each measurement object and the data acquisition parameters) includes:

[0068] Determine the flight altitude corresponding to the scale of each engineering drawing based on the scale of each measurement object in each engineering drawing, the corresponding minimum ground resolution, and the data acquisition parameters, including:

[0069] Use the following formula to calculate the first flight altitude:

[0070] The second flight altitude is calculated using the following formula:

[0071] Among them, F h1 and F h2 are the first flight altitude and the second flight altitude, F l is the focal length of the sensor, I w is the width of the image captured by the sensor, I h is the height of the sensor taking the image, GSD is the minimum ground resolution, S w is the sensor width, S h is the sensor height.

[0072] Determine the minimum value of the first flight altitude and the second flight altitude as the flight altitude corresponding to each scale of the engineering drawing;

[0073] In this embodiment of the present invention, the flight altitude is the height of the measured object, which can also be referred to as the distance from the measured object. This calculation and verification are performed using data from the DJI Phantom 4 RTK aircraft and its camera. Using data collected by the DJI Phantom 4 RTK aircraft, the relationship between the drone's flight altitude Fh, the mapping scale A, and the output digital image accuracy (DPI) B is as follows:

[0074] Verification: When a 1:500 topographic map is required and it is used for 300dpi digital image output,

[0075] In step 105, a flight mission is planned for each measurement object according to the measurement range of each measurement object to obtain a mission planning result;

[0076] In one embodiment, performing flight mission planning for each measurement object based on the measurement range of each measurement object to obtain a mission planning result includes:

[0077] If the terrain of the surface object is flat, the flight routes are arranged in a tic-tac-toe pattern within the measurement range of the surface object, and the heading overlap rate, side overlap rate, and gimbal angle are determined.

[0078] If the terrain of the planar object is non-flat (e.g., hilly, mountainous, or alpine), within the measurement range of the planar object, the flight path is first determined based on the flat terrain and a terrain model is created. Based on the terrain model, a crisscross terrain-simulating flight path is then planned, and the heading and lateral overlap rates, as well as the gimbal angle, are determined. The mission planning results include the flight path, heading and lateral overlap rates, and gimbal angle.

[0079] During specific implementation, the heading overlap rate is generally not less than 60%, and the lateral overlap rate is generally not less than 15%.

[0080] In one embodiment, performing flight mission planning for each measurement object based on the measurement range of each measurement object to obtain a mission planning result includes:

[0081] Within the measurement range of the linear object, a trapezoidal route is generated for each linear object according to the polyline of the linear object as a task planning result, wherein the cross section of the trapezoidal route includes the route surface area at the top of the trapezoid and the route surface areas on both sides of the trapezoid.

[0082] 3 is a schematic diagram of a linear object flight mission planning according to an embodiment of the present invention. The cross section of the trapezoidal route of the linear object is a trapezoidal cross section. The cross section of the measured object is used as a reference and is offset outward by a second preset length F. h =meters; the two vertical edges are rotated outward α degrees (α is equal to the pan / tilt tilt angle) with the upper vertex as the reference point; with the lowest point of the measured object as the base point, a perpendicular line is drawn to the rotated straight line to define the lower edge of the route; similarly, the two vertices on the opposite side are generated; these are connected to form a trapezoidal cross-section of the measured object. Since the linear heritage has been split into several continuous straight lines, forming a polyline, this method is used to generate trapezoidal cross-sections at both ends of the line, thereby obtaining the three route areas at the top and sides. The above steps can prevent the impact of vegetation at the roots of the heritage on flight.

[0083] In one embodiment, performing flight mission planning for each measurement object based on the measurement range of each measurement object to obtain a mission planning result includes:

[0084] Generate a first trapezoidal route section of the point-shaped object within the measurement range, and retain the route surface areas on both sides of the trapezoid in the first trapezoidal route section as a first supplementary range of the measurement range;

[0085] Facing the preset special position of the point-shaped object, a second trapezoidal route section of the preset special position is generated, and the route surface areas on both sides of the trapezoid in the second trapezoidal route section are retained as the second supplementary range of the measurement range;

[0086] A flight route is determined according to the measurement range, the first supplementary range, and the second supplementary range as a mission planning result.

[0087] In a specific implementation, since the measurement range of the point-shaped object has been extended outward by the third preset length F based on the five reference planes of the point-shaped object, h Meters, the measurement range at this time is the first part of the flight area, and then the first trapezoidal route section of the point object is generated according to the method of generating a trapezoidal route for a linear object, and the route area on both sides of the trapezoid in the first trapezoidal route section is retained as the first supplementary range of the measurement range; the special positions are preset as the eaves of the building, indoor areas, etc., and the second trapezoidal route section is generated, and the route area on both sides of the trapezoid in the second trapezoidal route section is retained as the second supplementary range of the measurement range.

[0088] In one embodiment, step 106 (processing the image data to generate a two-dimensional digital product and a three-dimensional digital product) includes:

[0089] De-redundant data is performed on the image data to obtain first image data; this step can ensure the quality and consistency of the image data;

[0090] Use hybrid aerotriangulation to synchronously adjust the first image data to obtain the second image data. This synchronous adjustment can obtain more accurate camera pose and three-dimensional coordinates of the ground object, which helps improve the geometric accuracy of the subsequent three-dimensional model.

[0091] Performing dense image matching on the second image data to obtain feature points and textures of the second image data and generate a three-dimensional model with high-density depth information; when performing dense image matching, the building material and risk type of the measured object may be considered;

[0092] Projecting the second image data onto the generated three-dimensional model to obtain a realistic and detailed texture on the three-dimensional model, wherein the three-dimensional model is a three-dimensional digital product; this step may be referred to as coloring the three-dimensional model; this step can improve the visual quality of the three-dimensional model;

[0093] Extract two-dimensional remote sensing maps from three-dimensional digital products as two-dimensional digital products.

[0094] During specific implementation, the extracted two-dimensional remote sensing maps include plane remote sensing maps, elevation remote sensing maps and perspective views of remote sensing maps at different angles.

[0095] In one embodiment, step 107 (building digital twin models of different precisions based on the two-dimensional digital product and the three-dimensional digital product, and forming a linear cultural heritage digital twin) includes:

[0096] Based on the two-dimensional and three-dimensional digital results and the digital twin accuracy system, digital twin models of different accuracies are constructed. Among them, the accuracies include general mapping, architectural mapping, and detailed mapping. The digital twin model is a model established for the ground object target.

[0097] According to the principle of accuracy first, digital twin models of different accuracies are integrated into a digital twin comprehensive model. Specifically, the digital twin model of the detailed drawing is used to replace the repeated areas in the digital twin model of the building drawing to obtain an intermediate model. The intermediate model is then used to replace the repeated areas in the digital twin model of the general drawing to form a digital twin comprehensive model.

[0098] Record the scales of various engineering drawings; among them, general drawing includes engineering drawings of 1:500, 1:1000, and 1:2000 scales; architectural drawing includes engineering drawings of 1:100, 1:150, 1:200, and 1:300 scales; detailed drawing includes engineering drawings of 1:1, 1:2, 1:5, 1:10, 1:15, 1:20, 1:25, 1:30, and 1:50 scales;

[0099] Based on the digital twin comprehensive model, the semantic information of the smallest building units of linear cultural heritage is organized. Specifically, image segmentation and deep learning techniques are used to identify and count the number of damage distribution and characteristics (such as crack width and collapsed area) of the smallest building units of linear cultural heritage (such as bricks and stones) in the digital twin comprehensive model as semantic information.

[0100] The digital twin comprehensive model, the scale and semantic information of various engineering drawings are integrated, and connected to the deployed Internet of Things data, climate and disaster data to form a linear cultural heritage digital twin. Disaster data can be earthquake disaster data.

[0101] In the method proposed in an embodiment of the present invention, a digital twin precision system for cultural heritage data collection is established, and each digital twin precision system is used to represent engineering drawings of different scales and the corresponding minimum ground resolution; according to the digital twin precision system, the measurement range of different measurement objects of the cultural heritage is determined on the satellite map; the data collection parameters of the drone remote sensing equipment combination for each measurement object are determined; according to the minimum ground resolution corresponding to each measurement object and the data collection parameters, the flight altitude is determined; according to the measurement range of each measurement object, flight mission planning is performed for each measurement object to obtain mission planning results; image data collected by the drone remote sensing equipment combination is obtained, and the image data is processed to generate two-dimensional digital results and three-dimensional digital results, wherein the image data is obtained by the drone remote sensing equipment combination according to the data collection parameters, the flight altitude and the mission planning results for linear cultural heritage; based on the two-dimensional digital results and the three-dimensional digital results, digital twin models of different precisions are constructed to form a digital twin of linear cultural heritage. Through the above steps, the solution proposed in the embodiment of the present invention can perform measurement range analysis and flight mission planning for different measurement objects, thereby realizing accurate and efficient acquisition of image data. After subsequent processing of the image data, a linear cultural heritage digital twin is formed, providing a comprehensive and effective solution for the digital protection and exhibition of cultural heritage, and providing scientific, effective and timely input support for the cultural heritage digital twin.

[0102] An embodiment of the present invention further proposes a linear cultural heritage data collection device based on drone remote sensing, the principle of which is similar to the linear cultural heritage data collection method based on drone remote sensing, and will not be repeated here.

[0103] FIG4 is a schematic diagram of a linear cultural heritage data acquisition device based on drone remote sensing according to an embodiment of the present invention, comprising:

[0104] A digital twin precision system establishment module 401 is used to establish a digital twin precision system for cultural heritage data collection, where each digital twin precision system is used to represent engineering drawings of different scales and the corresponding minimum ground resolution;

[0105] a measurement range determination module 402 for determining the measurement ranges of different measurement objects of the cultural heritage on a satellite image based on the digital twin accuracy system;

[0106] The data acquisition parameter determination module 403 is used to determine the data acquisition parameters of the UAV remote sensing device combination for each measurement object;

[0107] A flight altitude determination module 404 is configured to determine a flight altitude based on a minimum ground resolution corresponding to each measurement object and the data acquisition parameters;

[0108] The flight mission planning module 405 is used to plan a flight mission for each measurement object according to the measurement range of each measurement object and obtain a mission planning result;

[0109] Image data acquisition and processing module 406 is used to obtain image data collected by the UAV remote sensing device assembly, process the image data, and generate two-dimensional and three-dimensional digital products, wherein the image data is obtained by the UAV remote sensing device assembly through data acquisition of linear cultural heritage according to the data acquisition parameters, the flight altitude, and the mission planning results;

[0110] The linear cultural heritage digital twin construction module 407 is used to construct digital twin models of different precisions based on two-dimensional digital achievements and three-dimensional digital achievements, and form a linear cultural heritage digital twin.

[0111] In one embodiment, the digital twin accuracy system establishment module is specifically used to:

[0112] Determine the target scale system for digital twins of cultural heritage data collection. The target scale system includes the scale of the existing environment associated with general mapping, the scale of individual buildings associated with architectural mapping, and the scale of disease characteristics associated with detailed mapping. Among them, general mapping, architectural mapping, and detailed mapping are engineering drawings, and the scale of the existing environment, the scale of individual buildings, and the scale of disease characteristics are the target sizes of land features.

[0113] Determine the digital twin accuracy system corresponding to the target scale system of the digital twin. The digital twin accuracy system includes the scale of each engineering drawing and the corresponding minimum ground resolution. The minimum ground resolution is the accuracy of the ground object size.

[0114] In one embodiment, the digital twin accuracy system establishment module is specifically used to:

[0115] Determine the scale for each type of engineering drawing;

[0116] The following formula is used to determine the minimum ground resolution for each engineering drawing based on its scale:

[0117] Among them, GSD is the minimum ground resolution, meters / pixel, A is the scale of engineering drawings, and B is the digital image accuracy, pixels / inch.

[0118] In one embodiment, the measurement range determination module is specifically configured to:

[0119] When the measurement object is a planar object, on the satellite image, the linear cultural heritage body is described as multiple continuous straight line segments, with the inflection points of the curvature change of the linear cultural heritage body as the connection points. The linear cultural heritage body is extended to both sides by a first preset length to generate the measurement range of the planar object. The planar object is all the land features involved in the overall map mapping and associated endowment environment scale.

[0120] When the measurement object is a linear object, on a satellite image, the linear cultural heritage body is described as a polyline composed of continuous straight lines, with the curvature turning points of the linear cultural heritage body as breakpoints. The polyline is used as a track, and the cross-section width of the linear cultural heritage body at each breakpoint plus a second preset length is used as the cross-section to generate the measurement range of the linear object. The linear object is all ground objects involved in the scale of the building unit associated with the architectural drawing, and the polyline is the centerline of the linear measurement area.

[0121] When the measurement object is a point object, on the satellite image, the corner points of a single independent point object are connected and extended outward by a third preset length to generate the measurement range of the point object. The point object is all the ground objects involved in the detailed mapping associated disease characteristic scale.

[0122] In one embodiment, the drone remote sensing equipment combination includes a drone gimbal and a sensor; the data acquisition parameters include the focal length of the sensor, the width of the image captured by the sensor, the height and sensor width of the image captured by the sensor, and the rotatable angle of the drone gimbal.

[0123] In one embodiment, the flight altitude determination module is specifically configured to:

[0124] Use the following formula to calculate the first flight altitude:

[0125] The second flight altitude is calculated using the following formula:

[0126] Among them, F h1 and F h2 are the first flight altitude and the second flight altitude, F l is the focal length of the sensor, I w is the width of the image captured by the sensor, I h is the height of the sensor taking the image, GSD is the minimum ground resolution, S w is the sensor width, S h is the sensor height.

[0127] The minimum value of the first flight height and the second flight height is determined to be the flight height corresponding to the scale of each engineering drawing.

[0128] In one embodiment, the flight mission planning module is specifically configured to:

[0129] If the terrain of the surface object is flat, the flight routes are arranged in a tic-tac-toe pattern within the measurement range of the surface object, and the heading overlap rate, side overlap rate, and gimbal angle are determined.

[0130] If the terrain of the planar object is non-flat, within the measurement range of the planar object, the flight route is first determined based on the flat terrain and a terrain model is created. Based on the terrain model, a crisscross terrain-simulating flight route is then planned, and the heading overlap rate, lateral overlap rate, and gimbal angle are determined. The mission planning results include the flight route, heading overlap rate, lateral overlap rate, and gimbal angle.

[0131] In one embodiment, the flight mission planning module is specifically configured to:

[0132] Within the measurement range of the linear object, a trapezoidal route is generated for each linear object according to the polyline of the linear object as a task planning result, wherein the cross section of the trapezoidal route includes the route surface area at the top of the trapezoid and the route surface areas on both sides of the trapezoid.

[0133] In one embodiment, the flight mission planning module is specifically configured to:

[0134] Generate a first trapezoidal route section of the point-shaped object within the measurement range, and retain the route surface areas on both sides of the trapezoid in the first trapezoidal route section as a first supplementary range of the measurement range;

[0135] Facing the preset special position of the point-shaped object, a second trapezoidal route section of the preset special position is generated, and the route surface areas on both sides of the trapezoid in the second trapezoidal route section are retained as the second supplementary range of the measurement range;

[0136] A flight route is determined according to the measurement range, the first supplementary range, and the second supplementary range as a mission planning result.

[0137] In one embodiment, the image data acquisition and processing module is specifically configured to:

[0138] De-redundant data is performed on the image data to obtain first image data;

[0139] Synchronously adjusting the first image data using hybrid aerotriangulation to obtain second image data;

[0140] Performing dense image matching on the second image data to obtain feature points and texture of the second image data, and generating a three-dimensional model with high-density depth information;

[0141] Projecting the second image data onto the generated three-dimensional model to obtain a texture with realism and details on the three-dimensional model, wherein the three-dimensional model is a three-dimensional digital product;

[0142] Extract two-dimensional remote sensing maps from three-dimensional digital products as two-dimensional digital products.

[0143] In one embodiment, the linear cultural heritage digital twin construction module is specifically used to:

[0144] Based on the two-dimensional digital results and three-dimensional digital results, and based on the digital twin precision system, digital twin models of different precisions are constructed;

[0145] According to the principle of accuracy first, digital twin models of different accuracies are integrated into a comprehensive digital twin model;

[0146] Record the scales of various engineering drawings;

[0147] Organize the semantic information of the smallest building unit of linear cultural heritage based on the digital twin comprehensive model;

[0148] Integrate the digital twin comprehensive model, the scales and semantic information of various engineering drawings, and connect to the deployed Internet of Things data, climate meteorology and disaster data to form a linear cultural heritage digital twin.

[0149] To sum up, in the device proposed in the embodiment of the present invention, in the method proposed in the embodiment of the present invention, a digital twin precision system for cultural heritage data collection is established, and each digital twin precision system is used to represent engineering drawings of different scales and the corresponding minimum ground resolution; according to the digital twin precision system, the measurement range of different measurement objects of the cultural heritage is determined on the satellite map; the data collection parameters of the drone remote sensing equipment combination for each measurement object are determined; according to the minimum ground resolution corresponding to each measurement object and the data collection parameters, the flight altitude is determined; according to the measurement range of each measurement object, flight mission planning is performed for each measurement object to obtain mission planning results; image data collected by the drone remote sensing equipment combination is obtained, and the image data is processed to generate two-dimensional digital results and three-dimensional digital results, wherein the image data is obtained by the drone remote sensing equipment combination according to the data collection parameters, the flight altitude and the mission planning results, by collecting data on linear cultural heritage; according to the two-dimensional digital results and the three-dimensional digital results, digital twin models of different precisions are constructed, and a digital twin of linear cultural heritage is formed. Through the above steps, the solution proposed in the embodiment of the present invention can perform measurement range analysis and flight mission planning for different measurement objects, thereby realizing accurate and efficient acquisition of image data. After subsequent processing of the image data, a linear cultural heritage digital twin is formed, providing a comprehensive and effective solution for the digital protection and exhibition of cultural heritage, and providing scientific, effective and timely input support for the cultural heritage digital twin.

[0150] An embodiment of the present invention also provides a computer device. Figure 5 is a schematic diagram of a computer device in an embodiment of the present invention. The computer device 500 includes a memory 510, a processor 520, and a computer program 530 stored in the memory 510 and executable on the processor 520. When the processor 520 executes the computer program 530, the above-mentioned linear cultural heritage data collection method based on drone remote sensing is implemented.

[0151] An embodiment of the present invention also provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the above-mentioned linear cultural heritage data collection method based on drone remote sensing.

[0152] An embodiment of the present invention further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, it implements the above-mentioned linear cultural heritage data collection method based on drone remote sensing.

[0153] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0154] The present invention is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0155] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0156] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0157] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for collecting linear cultural heritage data based on drone remote sensing, characterized in that, Including: Establish a digital twin accuracy system for cultural heritage data collection, which is used to represent engineering drawings at different scales and the corresponding minimum ground resolutions; Determine the measurement ranges of different measurement objects of cultural heritage on the satellite map according to the digital twin accuracy system; Determine the data collection parameters of the UAV remote sensing equipment combination for each measurement object; Determine the flight altitude according to the scale of each engineering drawing of each measurement object, the corresponding minimum ground resolution, and the data collection parameters; Perform flight mission planning for each measurement object according to the measurement range of each measurement object to obtain the mission planning result; Obtain the image data collected by the UAV remote sensing equipment combination, and process the image data to generate two-dimensional digital results and three-dimensional digital results, where the image data is obtained by the UAV remote sensing equipment combination for data collection of linear cultural heritage according to the data collection parameters, the flight altitude, and the mission planning result; Construct digital twin models with different precisions according to the two-dimensional digital results and three-dimensional digital results, and form a digital twin body of linear cultural heritage.

2. The method according to claim 1, characterized in that, Establish a digital twin accuracy system for cultural heritage data collection, including: Determine the target scale system of the digital twin for cultural heritage data collection. The target scale system includes the general drawing mapping associated deposit environment scale, the building drawing associated building monomer scale, and the detail drawing associated disease feature scale. Among them, the general drawing, the building drawing, and the detail drawing are engineering drawings, and the deposit environment scale, the building monomer scale, and the disease feature scale are the sizes of ground object targets; Determine the digital twin accuracy system corresponding to the target scale system of the digital twin. The digital twin accuracy system includes the scale of each engineering drawing and the corresponding minimum ground resolution. The minimum ground resolution is the accuracy of the size of the ground object target that can be accurately distinguished on the image data collected by the UAV.

3. The method according to claim 2, wherein Determine the digital twin accuracy system corresponding to the target scale system of the digital twin, including: Determine the scale of each engineering drawing; Use the following formula to determine the minimum ground resolution corresponding to each engineering drawing according to the scale of each engineering drawing: Among them, GSD is the minimum ground resolution, m / pixel, A is the scale of the engineering drawing, and B is the digital image accuracy, pixel / inch.

4. The method according to claim 1, wherein According to the digital twin accuracy system, determine the measurement ranges of different measurement objects of cultural heritage on the satellite map, including: When the measurement object is a planar object, on the satellite map, taking the inflection points of the curvature change of the linear cultural heritage body as connection points, describe the linear cultural heritage body as multiple continuous straight line segments, and extend a first preset length to both sides to generate the measurement range of the planar object. The planar object is all ground object targets involved in the general drawing mapping associated deposit environment scale; When the measurement object is a linear object, on the satellite map, taking the curvature turning points of the linear cultural heritage body as break points, describe the linear cultural heritage body as a polyline composed of continuous straight lines. Taking the polyline as the track and the cross-section width of the linear cultural heritage body at each break point plus a second preset length as the cross-section, generate the measurement range of the linear object. The linear object is all ground object targets involved in the building drawing associated building monomer scale, and the polyline is the center line of the linear measurement area; When the measurement object is a point object, on the satellite map, connect the corner points of a single independently existing point object and expand it outward by a third preset length to generate the measurement range of the point object, where the point object is all the ground object targets involved in the detailed drawing mapping associated disease feature scale.

5. The method according to claim 1, characterized in that, The UAV remote sensing equipment combination includes a UAV gimbal and a sensor; the data acquisition parameters include the focal length of the sensor, the width of the image captured by the sensor, the height of the image captured by the sensor, the width of the sensor, and the rotatable angle of the UAV gimbal.

6. The method according to claim 5, wherein According to the scale of each measurement object in each engineering drawing, the corresponding minimum ground resolution, and the data acquisition parameters, determine the flight altitude corresponding to the scale of each engineering drawing, including: The first flight altitude is calculated using the following formula: The second flight altitude is calculated using the following formula: Among them, F h1 and F h2 are the first flight altitude and the second flight altitude respectively, F l is the focal length of the sensor, I w is the width of the image captured by the sensor, I h is the height of the image captured by the sensor, GSD is the minimum ground resolution, S w is the width of the sensor, S h is the height of the sensor; Determine the minimum value of the first flight altitude and the second flight altitude as the flight altitude corresponding to the scale of each engineering drawing.

7. The method according to claim 4, wherein According to the measurement range of each measurement object, conduct flight mission planning for each measurement object to obtain the mission planning result, including: If the terrain of the planar object is flat, within the measurement range of the planar object, determine that the flight route is arranged in a grid pattern, and determine the heading overlap rate, the side overlap rate, and the gimbal angle; If the terrain of the planar object is not flat, within the measurement range of the planar object, first determine the flight route according to the flat terrain and establish a terrain model, and then plan a grid-shaped terrain-following flight route based on the terrain model, and determine the heading overlap rate, the side overlap rate, and the gimbal angle. The mission planning result includes the flight route, the heading overlap rate, the side overlap rate, and the gimbal angle.

8. The method according to claim 4, wherein According to the measurement range of each measurement object, conduct flight mission planning for each measurement object to obtain the mission planning result, including: Within the measurement range of the linear object, generate a trapezoidal flight route for each linear object according to the polyline of the linear object as the mission planning result, where the cross-section of the trapezoidal flight route includes the flight route area at the top of the trapezoid and the flight route areas on both sides of the trapezoid.

9. The method according to claim 4, wherein According to the measurement range of each measurement object, conduct flight mission planning for each measurement object to obtain the mission planning result, including: Within the measurement range of the point object, generate the first trapezoidal flight route cross-section of the point object, and retain the flight route areas on both sides of the trapezoid in the first trapezoidal flight route cross-section as the first supplementary range of the measurement range; Facing the preset special position of the point object, generate the second trapezoidal flight route cross-section of the preset special position, and retain the flight route areas on both sides of the trapezoid in the second trapezoidal flight route cross-section as the second supplementary range of the measurement range; According to the measurement range, the first supplementary range, and the second supplementary range, determine the flight route as the mission planning result.

10. The method according to claim 1, characterized in that, Process the image data to generate two-dimensional digital results and three-dimensional digital results, including: Remove redundant data from the image data to obtain the first image data; Use hybrid aerial triangulation encryption to synchronously adjust the first image data to obtain the second image data; Conduct image dense matching on the second image data to obtain the feature points and textures of the second image data, and generate a three-dimensional model with high-density depth information; Project the second image data onto the generated 3D model to obtain textures with a sense of reality and details on the 3D model, where the 3D model is a 3D digital result. Extract a 2D remote sensing map from the 3D digital result as a 2D digital result.

11. The method according to claim 1, wherein According to the 2D digital result and the 3D digital result, construct digital twin models with different precisions and form a digital twin body of linear cultural heritage, including: According to the 2D digital result and the 3D digital result, based on the digital twin precision system, construct digital twin models with different precisions. According to the principle of precision priority, integrate digital twin models with different precisions into a digital twin comprehensive model. Record the scales of various engineering drawings. According to the digital twin comprehensive model, sort out the semantic information of the minimum building units of linear cultural heritage. Integrate the digital twin comprehensive model, the scales of various engineering drawings, and the semantic information, and connect to the deployed Internet of Things data, climate meteorology, and disaster data to form a digital twin body of linear cultural heritage.

12. A data acquisition device for linear cultural heritage based on UAV remote sensing, characterized in that, Including: A digital twin precision system establishment module for establishing a digital twin precision system for cultural heritage data collection, where each digital twin precision system is used to represent engineering drawings with different scales and the corresponding minimum ground resolutions. A measurement range determination module for determining the measurement ranges of different measurement objects of cultural heritage on the satellite map according to the digital twin precision system. A data collection parameter determination module for determining the data collection parameters of the UAV remote sensing equipment combination for each measurement object. A flight altitude determination module for determining the flight altitude according to the minimum ground resolution corresponding to each measurement object and the data collection parameters. A flight mission planning module for performing flight mission planning for each measurement object according to the measurement range of each measurement object to obtain a mission planning result. An image data collection and processing module for obtaining the image data collected by the UAV remote sensing equipment combination, processing the image data to generate a 2D digital result and a 3D digital result, where the image data is obtained by the UAV remote sensing equipment combination through data collection of linear cultural heritage according to the data collection parameters, the flight altitude, and the mission planning result. A linear cultural heritage digital twin body construction module for constructing digital twin models with different precisions according to the 2D digital result and the 3D digital result and forming a digital twin body of linear cultural heritage.

13. A computer device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method according to any one of claims 1 to 11.

14. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, and when the computer program is executed by the processor, it implements the method according to any one of claims 1 to 11.

15. A computer program product, characterized in that, The computer program product includes a computer program, and when the computer program is executed by the processor, it implements the method according to any one of claims 1 to 11.

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