130 results about "Terrain modeling" patented technology

The invention discloses a high-precision topographic surveying and mapping system and method based on an unmanned aerial vehicle, and particularly relates to the technical field of unmanned aerial vehicle surveying and mapping, and the method comprises the following steps: carrying out the topographic modeling before a task, recognizing GNSS shielding, and dividing a navigation region; gNSS, INS and visual inertial navigation positioning information are fused in flight, the weight is dynamically adjusted, and historical trajectory constraint is combined; constructing a closed-loop detection mechanism to carry out error feedback and feedforward prediction; confidence is calculated according to image definition, IMU stability and time synchronization deviation, high confidence points are screened for DEM reconstruction, local heavy flight is triggered by low confidence points, and surveying and mapping precision and reliability are improved; according to the method, the autonomous navigation and positioning precision of the unmanned aerial vehicle in a complex environment is improved, the quality control of surveying and mapping data and the DEM reconstruction reliability are enhanced, the closed-loop self-correction and feed-forward error prediction capabilities are provided, and the stability, precision and intelligent level of the system are remarkably improved.

The invention relates to the technical field of unmanned aerial vehicles, and discloses an unmanned aerial vehicle parking apron dynamic landing point adjustment method and system based on environment awareness, and the method comprises the steps: obtaining environment data and flight parameters, constructing a three-dimensional terrain grid model, and analyzing the stability; loading obstacle data and path constraints to generate a comprehensive evaluation model, and simulating to obtain regulation and control data; training the model to generate initial adjustment parameters, and combining the parameters with the model to obtain dynamic adjustment simulation information; constructing a multi-path optimization model to obtain optimal parameters; and combining real-time sensing to generate a safety probability, and adjusting a landing strategy. The system comprises a data acquisition module, a terrain modeling module and the like. According to the scheme, intelligent optimization and real-time adjustment of a landing point are realized through multi-dimensional environment perception and dynamic modeling, the landing safety and reliability of the unmanned aerial vehicle in a complex environment are improved, and the method is suitable for an intelligent landing scene of the unmanned aerial vehicle.

The invention relates to the technical field of data processing, in particular to an earthwork balancing method based on discrete elevation points and a free-form surface creation technology, and the method comprises the steps: generating topographic feature partition tags through an improved DBSCAN density clustering algorithm, and constructing a regularized elevation field in combination with octree and R * tree mixed indexes; generating an elevation standard deviation thermodynamic diagram based on Gaussian process regression, and outputting a multi-target digging and filling scheme set in combination with an FEM-DEM coupling model; a multi-layer graph model fused with soil bearing capacity is constructed, a collision-free construction path is optimized through an improved D * Lite algorithm, a positioning track and a planning deviation are fused by using Kalman filtering, and an online sequence extreme learning machine is triggered to realize dynamic updating of the model. According to the method, the complex terrain modeling efficiency and the earthwork volume calculation precision are improved, the resource allocation path is optimized, the construction cost is reduced, and the problem of excavation and filling imbalance caused by data discreteness and modeling staticization in a traditional method is solved.

The invention discloses a complex terrain three-dimensional modeling and earthwork volume calculation method based on a multi-source fusion point cloud, belongs to the technical field of surveying and mapping and engineering surveying, and mainly solves the problems of low terrain modeling precision and insufficient earthwork calculation efficiency in a complex scene. The method comprises the following steps: constructing a ground-air integrated multi-source sensing network to synchronously acquire laser point cloud, multi-view images and positioning data; adopting PointNet + +-based initial registration and multi-scale ICP fine registration fusion to generate a unified point cloud; combining semantic segmentation and penetration probability filtering to accurately extract a digital elevation model; constructing a similar triangular prism voxel model by using a constrained Delaunay triangulation network; and finally, the earth volume is rapidly calculated by adopting a GPU parallel voxel cutting and filling algorithm, so that high-precision terrain modeling and rapid engineering quantity calculation are realized, and the method can be efficiently and reliably applied to large-scale projects such as roads and mines.

The invention discloses a multi-sensor fusion underwater SLAM system and method based on adaptive weight adjustment, and the system comprises a multi-modal sensor module, a data preprocessing and synchronization module, an adaptive weight adjustment module, a multi-sensor data fusion module, an SLAM calculation and map updating module, and an SLAMS result output module. And the adaptive weight adjustment module monitors the data quality of each sensor of the multi-modal sensor module in real time, and automatically adjusts the weight of each sensor according to the change of the underwater environment. The underwater positioning and navigation system can realize stable underwater positioning and navigation in an environment with insufficient light, complex obstacles or turbid water, and is especially suitable for tasks such as underwater exploration, detection and complex terrain modeling. Compared with the traditional SLAM technology, the method provided by the invention overcomes the limitation of a single data source by adjusting the weight of the sensor in real time, and significantly improves the adaptability and precision of the SLAM system in different underwater environments.

The invention relates to the technical field of reservoir storage capacity measurement, in particular to a reservoir storage capacity measurement method and system based on remote sensing and point cloud data, and the method comprises the following steps: extracting a terrain surface point set based on input remote sensing image data and point cloud data, and calculating a three-dimensional coordinate value, a curvature value and a point density value of each point; and comparing and classifying curvature and density data in combination with the change of the reservoir boundary. According to the method, through comprehensive application of remote sensing image data and point cloud data, three-dimensional coordinates, curvature values and point density values are adopted to accurately extract topographic features, scientific division and feature description of sub-regions are achieved, refined three-dimensional grid parameters are generated through fitting and interpolation calculation, and the accuracy of the three-dimensional grid parameters is improved. The terrain modeling precision and the space geometry description capability of a complex area are improved, boundary node coordinates and normal vectors are dynamically adjusted, the grid continuity is optimized, the integrity of a boundary transition area is ensured, and the boundary complex volume is accurately described by adopting unit volume subdivision and boundary correction.

The invention discloses a three-dimensional terrain modeling analysis and adaptive navigation system and method, and relates to the technical field of navigation. A laser radar in the system is used for acquiring point cloud data of an area where a to-be-navigated device is located in real time; the IMU is used for measuring the acceleration and the angular velocity of a to-be-navigated device in real time; the data fusion sub-module is used for preprocessing the point cloud data, the acceleration and the angular velocity in real time and fusing the preprocessed data; the three-dimensional map modeling sub-module is used for constructing a three-dimensional map model according to the point cloud data by adopting an SLAM algorithm in real time; the three-dimensional terrain analysis module is used for determining terrain features of all points in the three-dimensional map model in real time; and the adaptive navigation module is used for performing path planning on the to-be-navigated device according to the three-dimensional map model and the topographic features of each point in real time to realize navigation. According to the invention, the precision of original data can be improved, the positioning precision is improved, and accurate navigation is realized.

The invention provides a hydropower station reservoir water level prediction analysis method, a hydropower station reservoir water level prediction analysis system and a storage medium, and relates to the technical field of reservoir water level prediction. A unified modeling path from hydrological element collection to water level prediction is realized, a directed weighted graph reflecting a real hydrological conduction path is formed by fusing a digital elevation model and hydrological data, constructing a space node and a water flow connection relation thereof and giving edge weights, so that the water level prediction is not limited to point data analysis any more, and the water level prediction accuracy is improved. According to the method, modeling of collaborative change of hydrological states in a whole influence basin is changed, a unified framework fusing a terrain structure, a hydrological process and machine learning capability is constructed, coupling modeling of spatial distribution characteristics and time dynamic characteristics is achieved, and the precision and reliability of water level prediction are improved.

The invention relates to the technical field of geographic information processing, in particular to a land parcel line close-to-the-ground rendering method and system and a computer readable storage medium, and the method comprises the steps: obtaining a 3D model of a topographic region, and extracting ground point cloud data representing the topography from the 3D model of the topographic region; converting the ground point cloud data into a continuous terrain surface model through digital terrain modeling; determining a land parcel boundary point and a gradient thereof based on the terrain surface model, and selecting a corresponding interpolation method according to the gradient to perform encryption and smoothing processing of terrain data; and performing close-to-ground rendering of the land parcel boundary through a three-dimensional graphic rendering technology based on the topographic data and the land parcel boundary points after interpolation processing. According to the implementation of the method, the land parcel line can be accurately attached to the ground, and a more real and natural visual effect is presented.

The invention provides a three-dimensional terrain modeling method and system. The modeling method comprises the following steps: acquiring a plurality of aerial photos of a to-be-modeled region, wherein ground control points of the aerial photos are not marked; generating a first sparse point cloud set and a rough three-dimensional terrain model of the to-be-modeled region based on the aerial photo of each unmarked ground control point; automatically marking ground control points on each aerial photo based on the rough three-dimensional terrain model; generating a second sparse point cloud set of the to-be-modeled region based on the aerial photo of each marked ground control point; and generating a dense point cloud set and a fine three-dimensional terrain model of the to-be-modeled region based on the second sparse point cloud set. According to the modeling method provided by the invention, the marking speed is effectively improved while the marking precision of the ground control points is improved, and the efficiency of high-precision three-dimensional terrain modeling is remarkably improved on the whole.

The invention discloses an intelligent three-dimensional terrain modeling method and system based on surveying and mapping data, and relates to the technical field of surveying and mapping, and the method comprises the steps: carrying out the comprehensive calculation based on a local terrain complexity index LTCI and a terrain feature line stability index FLSI, and outputting an overall modeling quality index GMQI, and carrying out secondary comparison evaluation based on an overall modeling quality index GMQI result. And when an overall modeling quality index GMQI evaluation result shows that the overall modeling quality does not reach the standard, performing automatic iteration to trigger refined reconstruction, and performing gradual optimization according to a 40% point density improvement strategy every time until the overall modeling quality reaches the standard, thereby realizing global modeling quality control of the mountainous area infrastructure site selection area. According to the method, modeling consistency and detail precision are improved, modeling deviation caused by local terrain sudden change or structure instability is effectively avoided, and reliability and safety of the final three-dimensional terrain model in engineering design application are improved.

The invention relates to the technical field of river channel model construction, and provides a river channel model generation method and system and a medium, and the method comprises the steps: obtaining a remote sensing image and satellite height measurement data of a target river channel, extracting a river channel thalweg line based on the image, extracting feature points from a waterline, and giving an elevation value in combination with the height measurement data; dividing the river channel into independent interpolation areas on the left side and the right side by taking the thalweg as a boundary, and setting a direction attenuation coefficient and a distance attenuation coefficient according to the characteristics of the river reach; generating direction control points along the thalweg according to the minimum width of the dry-season river channel, calculating the local direction angle of each river section, and combining the direction angle, direction attenuation and distance attenuation coefficients to construct a weighting function; spatial interpolation is carried out on the feature points on the left side and the right side through the function, double-side digital elevation models are generated respectively, finally, a complete river channel model is obtained through splicing, and refined expression of the river channel terrain is achieved. According to the method, the precision and physical rationality of complex river channel terrain modeling can be improved.

The invention discloses a mountain photovoltaic layout optimization method and system based on multi-point illumination dynamic data, and relates to the technical field of photovoltaic construction, and the method comprises the steps: constructing a virtual mountain structure and configuring a three-dimensional landform stereo structure through mountain geographical and landform data; based on the historical illumination data, establishing an illumination simulation model, and quantifying the illumination performance of the virtual mountain structure; randomly arranging virtual photovoltaic modules in the photovoltaic layout area, determining position nodes and angles, and forming a virtual photovoltaic arrangement strategy; and calculating an illumination intensity accumulation parameter and a total parameter of each virtual photovoltaic module, evaluating layout optimization in combination with layout cost, and screening an optimization strategy. According to the method, through refined terrain modeling, dynamic illumination simulation and multi-target optimization, the energy efficiency and economical efficiency of mountain photovoltaic layout are remarkably improved, and scientific support is provided for planning of a complex terrain photovoltaic power station.

The invention discloses an airborne laser radar point cloud three-dimensional target detection method based on terrain guidance, and belongs to the technical field of three-dimensional target detection. The objective of the invention is to solve the problem that the existing three-dimensional target detection does not consider the influence caused by terrain complexity and target-background similarity, so that the detection effect needs to be improved. According to the invention, based on the VoxelNext network, a multi-stage terrain guidance module is introduced to predict terrain distribution and guide the processes of height compression, region-of-interest generation and proposal prediction, and effective combination of terrain modeling and pipeline detection is realized; according to the method, voxels are randomly sampled and grouped through a sparse feature enhancement module, middle layer features are aggregated, and two auxiliary tasks of foreground segmentation and voxel up-sampling are introduced to enhance the feature expression ability of the network.

The invention discloses a photovoltaic station unmanned aerial vehicle three-dimensional route planning method and system based on field angle self-adaption and terrain modeling. The method comprises the following steps: acquiring geographic position information of a photovoltaic panel; determining a vertical field angle according to the unmanned aerial vehicle image equipment parameters; generating a reference point based on geographic position information, performing horizontal clustering by adopting a density clustering algorithm to form an initial row group, and completing row-column grouping through linear fitting completion and correction of a row structure; dynamically determining a flight height for each waypoint through geometric model calculation based on a grouping result in combination with a vertical field angle and a pitch angle, and generating a three-dimensional waypoint; and determining a waypoint connection sequence based on a distance optimal principle, detecting and optimizing acute-angle turning, and generating a smooth three-dimensional flight path. According to the invention, full-automatic three-dimensional planning of the photovoltaic inspection route is realized, the system can adapt to complex terrains, the shooting quality is ensured, and the inspection efficiency is improved.

The invention provides a hydropower station reservoir area three-dimensional terrain modeling method and device based on multi-source data fusion, and relates to the technical field of three-dimensional terrain modeling, and the method comprises the steps: obtaining a multi-source data set containing point cloud data, image data, texture data and actual measurement data of a hydropower station reservoir area; preprocessing the multi-source data set to obtain a preprocessed data set; and according to the preprocessed data set, constructing a three-dimensional terrain model by using an improved Delou inner triangulation algorithm, a non-uniform rational B-spline surface reconstruction technology and a Laplacian smoothing operator. The geometric accuracy and the natural form of the three-dimensional terrain model can be remarkably improved.

The invention discloses a water-land integrated all-terrain DEM surveying method and system based on UAV-USV-GIS, and belongs to the field of terrain surveying. The method comprises the steps of determining a research area range, planning an unmanned aerial vehicle route, and laying image control points; performing aerial survey on the planned route by using an unmanned aerial vehicle to obtain ground point cloud data and images, and respectively processing the ground point cloud data and images into a land DEM and an orthoimage; the boundaries of the subsidence water area are extracted through the orthoimages, the measurement route of the unmanned ship is planned, and underwater topographic data are measured; processing the underwater topographic data, generating a water area DEM, uniformly selecting inspection points by using RTK and sounding equipment to carry out sampling measurement on the underwater elevation, and verifying the accuracy of the water area DEM underwater topographic data; and fusing the land DEM and the water area DEM to generate a complete water-land integrated all-terrain DEM. The technical bottlenecks that the efficiency is low, the data at the junction of water and land is not accurate, and only the elevation data of a single area of the land or the water can be obtained in the subsidence water area terrain modeling by a traditional single measurement means are effectively solved.

The invention discloses a submarine topography real-time surveying and mapping system based on a sonar array, and relates to the technical field of sonar topography surveying and mapping. The system comprises a sonar array, a data acquisition and preprocessing module, a control and communication module, a data processing and terrain modeling module and a power supply module. According to the sonar array, a self-adaptive matrix is formed by multi-frequency-band sensors, real-time calibration, high-speed parallel sampling for data acquisition and advanced algorithm noise reduction are achieved, a control module optimizes parameters according to the environment, and communication is diversified and safe; the processing module adopts deep learning modeling, grids are divided according to curvature, a power supply adopts multi-source complementation and energy recovery, and energy is managed and distributed. The surveying and mapping precision is high, and the constructed three-dimensional model is accurate. The device adapts to complex marine environment and has strong stability. Multi-source power supply and energy recovery are adopted, the energy consumption is low, and the endurance is long; the system is excellent in data processing and analysis capability, integrates multi-source data, has the functions of safety protection, path planning and the like, and comprehensively guarantees efficient completion of surveying and mapping tasks.

The invention discloses an unmanned aerial vehicle route generation system which comprises a generation system body, the generation system body comprises a three-dimensional terrain modeling module, a multi-source sensor fusion module, an intelligent task planning module, a dynamic obstacle avoidance and safety module and a man-machine interaction and data management module, and the three-dimensional terrain modeling module is based on ASTER GDEM and DSM elevation data; the multi-source sensor fusion module is used for generating a three-dimensional digital elevation model (DEM) of an operation area, centimeter-level terrain matching is realized by combining an RTK positioning technology, and the multi-source sensor fusion module is used for integrating a laser radar, a visible light camera and an infrared sensor, collecting features of ground objects such as towers and vegetation in real time, and is used for dynamically adjusting an air route. The optimal route is automatically generated through an intelligent algorithm, manual intervention is reduced, route planning efficiency is remarkably improved, meanwhile, terrain adaptability can be enhanced, a terrain following algorithm is adopted, the flight height is automatically adjusted according to topographic relief, and accuracy and integrity of surveying and mapping data are ensured.

The invention relates to the technical field of three-dimensional modeling, in particular to a terrain modeling method and device based on a domestic three-dimensional graphic platform Railworks, and the method comprises the steps: collecting terrain data along a rail transit engineering project, and generating a structured original data pool; the method comprises the following steps: extracting and processing a discrete three-dimensional point set through a Railworks platform, and generating a triangular mesh by adopting a Gift Wrapping algorithm and a Delaunay triangulation algorithm; reconstructing a three-dimensional terrain surface model, adding an attribute database, and integrating elevation and gradient attributes according to industrial standards; and a downstream bridge and roadbed design module is connected through a data synchronization mechanism, so that design parameters are automatically updated. The device correspondingly realizes functions of each step. According to the method, the problems of high data security risk and low collaboration efficiency caused by dependence on foreign software are solved, an autonomous solution is provided, and the data processing security and the cross-professional design collaboration efficiency are improved.

The invention discloses an unmanned aerial vehicle autonomous path planning and high-precision surveying and mapping integrated system, and relates to the technical field of unmanned aerial vehicle surveying and mapping. The system comprises a terrain modeling module, a task configuration and scheduling module, a path planning module, an unmanned aerial vehicle flight control module, a surveying and mapping sensing module, a data caching and transmission module and a ground control and result processing module. The terrain modeling module constructs three-dimensional terrain modeling through remote sensing image interpretation and a digital elevation model; the path planning module fuses simulated annealing, an adaptive genetic algorithm and a large neighborhood search algorithm to realize route static optimization and multi-aircraft cooperative path generation; the flight control module autonomously completes flight according to the path instruction; the data caching module provides breakpoint resume and edge relay support; and the ground platform completes image processing, splicing modeling and result exporting. According to the invention, intelligent route planning and high-precision and multi-source surveying and mapping data acquisition under complex terrains are realized, and the surveying and mapping automation level and the data accuracy are remarkably improved.

The invention relates to the field of land reclamation engineering, in particular to a land reclamation engineering progress monitoring system based on time sequence image analysis, which comprises a data storage module, an engineering progress image recognition engine, an engineering quality detection module, a meteorological condition compensation module and an early warning module. A Riemannian geometric model of a terrain curved surface is constructed, a project progress is analyzed and quantified through a geodesic network, a project progress image recognition engine comprises an image registration module, a Riemannian geometric terrain modeling module and a geodesic analysis module, and the Riemannian geometric terrain modeling module constructs a terrain surface model through manifold parameterization and measurement tensor calculation. The geodesic analysis module quantifies engineering progress indexes such as the earthwork completion rate, the road hardening rate and the greening coverage rate based on geodesic network changes, the system further integrates quality evaluation functions such as slope stability detection and drainage system integrity detection, and the reliability of a monitoring result is improved through meteorological condition compensation.

The invention belongs to the technical field of radio wave propagation, particularly discloses a complex path ASF prediction method based on parameter optimization three-dimensional FDTD, and aims to solve the problem of ASF prediction errors caused by neglecting a transverse diffraction effect in a two-dimensional method and the problem of poor precision caused by accumulated phase errors when a traditional three-dimensional FDTD method is applied to large-area ASF prediction. By means of three-dimensional terrain modeling, the electromagnetic propagation characteristics of the complex irregular terrain are accurately presented, and therefore the accuracy of the ASF prediction result of the complex path is remarkably improved. In addition, according to the complex path ASF prediction method based on parameter optimization three-dimensional FDTD, dispersion optimization parameters are introduced, phase accumulation errors are reduced, and therefore the calculation efficiency is improved while the precision is guaranteed. The method can provide an efficient solution for ASF prediction in a large-scale complex terrain scene, and is more suitable for popularization and application in engineering.

The invention provides a river topography modeling method and device. The method comprises the following steps: acquiring section measurement data of each actually measured cross section in a target river; determining coordinate information of measurement points of all actually measured cross sections based on the section measurement data; performing cubic spline resampling on the actually measured cross section based on the coordinate information of the measurement points according to a preset number of sampling points to obtain coordinates of resampling points; performing linear interpolation on the adjacent actually-measured cross sections according to the coordinates of the re-sampling points in the river channel direction of the target river channel to obtain encrypted river channel cross sections and encrypted section data; and constructing a river channel model based on the encrypted cross section of the river channel and the encrypted section data. By means of cubic spline resampling and linear interpolation, terrain details are reserved, data requirements are reduced, cross section terrain data are supplemented, accurate supplement of the cross section of the river channel is achieved by means of the distance and gradient change between the cross section to be supplemented and the known sampling elevation cross section of the river channel, and therefore the model precision is improved.

The invention discloses a cloud-based surveying and mapping data processing method and system, and the method comprises the steps: collecting a multi-source surveying and mapping data set, and carrying out the data fusion of the multi-source surveying and mapping data set based on an improved hierarchical Transform model in a cloud platform; and establishing an MTL-DNN surveying and mapping data analysis model based on an MTL-DNN multi-task deep learning network, performing pruning operation on the model by using a fine-grained pruning device, and inputting the fused multi-source surveying and mapping data set into the target MTL-DNN surveying and mapping data analysis model to perform terrain modeling, ground feature classification and risk prediction, so that model parameters and calculation amount can be reduced, and the modeling efficiency is improved. The deployment efficiency is improved; accurate and efficient data support and decision basis are provided for the fields of surveying and mapping engineering, disaster early warning and the like.

The invention provides a marine electromagnetic take-off and landing transportation system based on a heavy-load unmanned aerial vehicle, and belongs to the technical field of unmanned aerial vehicle marine heavy-load transportation. The system comprises a shipborne electromagnetic take-off and landing subsystem, a shore-based electromagnetic take-off and landing subsystem, a heavy-load fixed-wing unmanned aerial vehicle, a marine low-altitude communication monitoring network and a comprehensive scheduling platform; the shipborne electromagnetic take-off and landing subsystem is of a multi-section coil array structure, the effective length of a coil array of the shipborne electromagnetic take-off and landing subsystem can be matched with the available space of a fishing ship deck, the take-off and landing distance is controllable, and therefore the problem of take-off and landing in the narrow space of the deck is solved. The shore-based electromagnetic take-off and landing subsystem is integrated with a three-dimensional terrain modeling module, the real-time environment of a landing area is pre-judged through laser radar and satellite remote sensing data, parameters of an electromagnetic propulsion device and an electromagnetic adsorption device of the shore-based electromagnetic take-off and landing subsystem are dynamically adjusted, then the shore-based electromagnetic take-off and landing subsystem adapts to rugged terrain, and the limitation that a traditional unmanned aerial vehicle depends on a flat take-off and landing field is avoided. And through data linkage and intelligent scheduling of multiple subsystems, the overall efficiency and reliability of marine transportation are greatly improved.

The invention discloses an underwater three-dimensional scene data completion method and system based on deep learning, relates to the technical field of computer graphics, and solves the technical problem of data missing caused by sound shadow shielding, strong filtering or semantic segmentation in submarine topography surveying and mapping data. According to the technical scheme, the method is characterized in that a synthetic training set based on programmed terrain modeling is constructed, and high-resolution and large-scale training data are provided; a double-discriminator generative adversarial network comprising a completion network, a context discriminator and a boundary quality discriminator is designed, stable convergence of the network is achieved through a three-stage progressive training strategy, and meanwhile self-adaptive processing facing different missing scales is achieved. Wherein the boundary quality discriminator is used for enhancing the boundary continuity of the complementation area. According to the method, rapid and high-quality completion of the multi-scale underwater three-dimensional data is realized, the structural consistency of the completion area is remarkably improved while the calculation efficiency is maintained, and an effective solution is provided for real-time underwater surveying and mapping application.

The invention belongs to the technical field of radio wave propagation, and particularly discloses a rugged topography path low-frequency ground wave propagation characteristic prediction method based on an FD algorithm, and the method comprises the steps: firstly building a 3DPE model under an irregular topography, then building a discretization matrix equation, combining boundary impedance conditions based on a unilateral approximation method, and then carrying out the iteration solving of a field matrix, thereby achieving the prediction of the rugged topography path low-frequency ground wave propagation characteristic. And finally, the magnetic field intensity and the secondary time delay of radio wave propagation are solved by utilizing a field result in the whole calculation area. According to the method, the problem that low-frequency ground wave propagation characteristics are not accurately represented in transverse irregular terrain modeling through a 2DPE method is effectively solved, and meanwhile, the limitation that low-frequency ground wave propagation prediction precision is insufficient in a complex rugged terrain environment through a traditional 3DPE model is overcome; theoretical guidance can be provided for performance optimization of a low-frequency radio navigation time service system, and the navigation positioning and time service precision in a complex terrain area is further improved.

The invention discloses a DEM map dynamic obstacle avoidance path planning method and system based on a rime algorithm, DEM terrain modeling, rime algorithm meteorological prediction and an improved A * path planning algorithm are combined, safe path planning in a dynamic environment is achieved, the method and system can be applied to unmanned aerial vehicle inspection (such as power line icing monitoring), mountain rescue, automatic driving and other scenes, and the method and system have good application prospects. The problems that a traditional A * algorithm is limited, multi-constraint fusion is difficult, pure real-time meteorological data lags behind and the like are solved, and a safer and more reliable path planning navigation scheme is formed.

The present invention discloses a method for modeling the underwater terrain of a lake based on a small amount of measured water depth data. The elevation profile collected along the central axis of the lake is regarded as the terrain skeleton of the lake. On the basis of determining the range of the lakeshore buffer zone, a series of lake cross-sections connecting the lakeshore and the central axis are constructed. Furthermore, the known elevation of the lakeshore is utilized, and the elevation values of the underwater area of the cross-section are inferred under the constraint of the measured elevation values on the central axis. Finally, based on the elevation of each cross-section and the central axis, spatial interpolation is used to construct the complete underwater terrain of the lake. This method does not require a full-lake survey, greatly reducing the time and economic costs of the field investigation work of the lake. The invention is applicable to the survey work of large lakes in areas with scarce data, and the constructed underwater terrain data of the lake will provide technical support for monitoring the dynamic changes of lake water resources and revealing the response characteristics of lake water resources to global changes, etc.