71 results about "Terrain modeling" patented technology

Method includes calculating a mean z coordinate value for points within the point cloud. An initial set of points is selected which have z coordinate values which deviate from the mean by at least an initial value. Thereafter, a triangulated irregular network (TIN) is constructed using the initial set of points. The method continues by determining if there is a significant point that exists among the points contained within an x, y extent of each triangle. If so, the TIN is updated to include the initial set of points and any significant points determined to exist within the triangles that form the TIN. Thereafter, the method continues by repeating the determining and the updating steps until there are no additional significant points found within the triangles.

The invention discloses a method for constructing a three-dimensional terrain vector model based on multi-beam sonar submarine measurement data, and relates to a method for constructing the three-dimensional vector terrain model with measurement data of multi-beam sonar, which solves the defect that a multi-beam ranging sensor can only provide discrete terrain elevation and can only query terrainparameters at a measurement point. The method is used for non-structural submarine terrain modeling and vector data retrieval. The method comprises the following steps of: acquiring a horizontal coordinate of a sampling point of the terrain of a submarine area and corresponding elevation data; defining a data structure of a terrain triangular net model according to characteristics of multi-beam sonar terrain measurement data; and finally, establishing a Delaunay triangular net vector model according to elevation data of each point of the multi-beam sonar terrain measurement and the data structure of a Delaunay triangular net.

The invention discloses a scanning laser based large-scale three-dimensional terrain modeling method. The scanning laser based large-scale three-dimensional terrain modeling method comprises the following steps of: firstly perceiving a surrounding environment through the scanning laser arranged on a mobile robot platform, and transforming original laser data into three-dimensional point clouds through coordinate transformation; secondly preprocessing the three-dimensional point clouds by adopting a median filter method, and constructing an octree structure to complete data storage; then carrying out fusion processing on data by adopting a Gaussian mixed model based randomization method to build a terrain environment model in real time; and finally detecting and processing an obstructed area positioned in the terrain environment model to further enhance model accuracy. In the invention, the problem of real-time modeling of a large-scale complex terrain is effectively solved by adopting the low-cost two-dimensional scanning laser; and good balance between the model accuracy and real-time property is realized in such a way that randomization processing is carried out on various uncertainties of the terrain environment model, and therefore, wide requirements of different fields, such as a GIS (Geographic Information System) system or unmanned autonomous navigation and the like, can be met.

The invention provides a method and a system for three-dimensional terrain modeling. The method comprises the following steps: reading altitude data; converting the altitude data to three-dimensional space coordinates and constructing a three-dimensional model; calculating the color information and normal vector of each vertex in the three-dimensional model; and rendering the three-dimensional model. By using a D3D (display 3-dimensional) three-dimensional engine for constructing the three-dimensional engine, the method can well meet the requirement of the three-dimensional terrain because the D3D three-dimensional engine can simulate modeling, illumination and the like, thereby omitting the construction of an illumination model and improving the system efficiency.

A terrain modeling method that fuses geometric characteristics and mechanical characteristics, and a terrain modeling system are provided in the present invention. The method includes steps of: obtaining color images and depth images of the detected region, performing a terrain semantic segmentation on the color images, and fusing ground semantic information obtained by the semantic segmentation and depth information contained in the depth images at the same time to generate the point clouds; mapping the point clouds to a raster map in a map coordinate system to generate corresponding rasters, and updating the elevation values to the corresponding rasters; and calculating the input images in terms of terra-mechanical characteristics, and updating calculation results to the corresponding rasters to generate a terrain model. A mechanical characteristic parameter is added to a terrain factor, and terrain characteristics are innovatively performed from two dimensions of geometric characteristic and mechanical characteristics.

The invention provides a method for water seepage, salt discharge and afforestation of a low-humidity saline and alkaline beach. The method comprises the following steps of: (1) performing landscape micro-terrain modeling finishing on a saline and alkaline land parcel to be governed to form orographic uplift afforestation areas and low-lying water catchment and salt discharge areas, and excavating drainage ditches in a direction from high to low; (2) turning over the earth surface; (3) excavating flexible water seepage and salt discharge tape burying ditches; (4) arranging flexible water seepage and salt discharge tapes at the bottoms of the ditches; (5) forming intersected water barrier ridges; (6) adding an organic fertilizer, and plowing and harrowing a surface layer; (7) arranging integrated flexible salt discharge and air permeation shafts; and (8) cultivating and sowing saline-alkali-resistant arbor-shrub-grass plants on saline and alkaline land which is comprehensively governed and improved. A set of feasible comprehensive technical method is provided for the comprehensive governance and afforestation of saline and alkaline land in large areas; and the method is favorable for improving the afforestation effect and level of saline and alkaline areas.

The invention discloses a terrain elevation sampling point encryption method taking morphology accuracy into account. The terrain elevation sampling point encryption method taking morphology accuracy into account includes the following steps: 1, initializing encryption application information; if the sampling point is determined as a linear element elevation sampling point, executing the second step; and if the sampling point is determined as an area elevation sampling point, executing the third step; 2, executing a linear element elevation sampling point encryption module, and according to the encryption step pitch, performing encryption processing on the linear element elevation sampling point; 3, executing an area elevation sampling point encryption module, and according to the encryption iteration frequency, performing encryption processing on the area elevation sampling point; and 4, generating an elevation sampling point encryption result file: recycling the memory applied during the encryption process and wiping the temporary external storage data; and updating the log file, counting and recording the encryption metadata information. The terrain elevation sampling point encryption method taking morphology accuracy into account can effectively solve the problem that terrain expression is distorted because of insufficient elevation sampling points during high precision terrain modeling process.

The invention discloses an unmanned aerial vehicle three-dimensional air route generation method based on fluid mechanics, and belongs to the field of air route planning. The method comprises the steps of firstly calculating a ball obstacle flow-around flow line on an original point along an x-axis incoming flow direction, obtaining a flow-around flow line of any incoming flow direction and any obstacle position in a plane by utilizing a rotary translation matrix, merging all flow lines into one flow line by adopting two ways according to the situation that whether the flow lines are partially overlapped or not, and finally processing the three-dimensional flow line according to the constraint of the unmanned aerial vehicle to obtain an unmanned aerial vehicle three-dimensional air route. By referring to the phenomenon that running water in the nature can avoid rocks, the fluid calculation is combined with the air route planning; meanwhile, considering the flight constraint of the unmanned aerial vehicle, when the terrain is relatively complicated, the three-dimensional flight obstacle avoiding air route which is smooth and easy for the unmanned aerial vehicle to fly can be planned. According to the method, simplicity in terrain modeling can be realized, the calculation workload is small, the constraint of the unmanned aerial vehicle can be satisfied, and convenience in realization is achieved.

The present invention discloses a terrain modeling and grid generation method and device. The method comprises the steps of: converting rule grid terrain elevation data to a form of X, Y and Z three-dimensional coordinates, performing triangular grid division, achieving consistence of a bottom-layer plane grid topological structure and generating multiple layers of triangular prism grids with suitable lengths of stretch. The technical problems are solved that a method for extraction of point coordinates from contour lines is employed to perform terrain modeling and grid generation, the generated grids are sparse and cannot realistically restore terrain details and if the number of extracted data points is added to caused slow speed of node searching and positioning and the computation amount is large in the prior art.

The invention discloses a culture-heritage three-dimensional-scene generation method which includes the following steps: step1: a culture-heritage remote-sensing data preparation step: obtaining geographic information data in a culture-heritage region and establishing a three-dimensional base database of the region; step2: a culture-heritage landform modeling and culture-heritage scene modeling step: obtaining texture and geometrical shape data of different objects in the culture-heritage region so as to generate a ground-object three-dimensional model of the region; step3: a culture-heritage three-dimensional spherical-system integrating step: obtaining building process data of the culture-heritage area and insetting landform and scene real-time measurement information of the area into the ground-object three-dimensional model according to a building process sequence and environment background information. The culture-heritage three-dimensional-scene generation method is capable of improving the speed and precision of large-scale culture heritage modeling and providing an integrated dynamic index of a culture-heritage single-body model and an environment model so that the method has complete management and update capabilities.

The invention discloses an air route planning method based on guide speed field in threat environment, and belongs to the field of air route planning. Subsistent threat affecting is fully considered, the threat is equivalent to a circular obstacle in a two-dimensional plane through the calculation, then traction field and avoidance field environment is established, the guide speed field is specially designed, controllability of the algorithm is improved, and the fast advantage of artificial potential field method is maintained. According to the method, planning speed can be directly obtained by calculation, the problem of incapability of reaching or entry barriers of the artificial potential field method can be overcome, and a smooth two-dimensional obstacle avoidance air route can be planned in real time. The air route planning method has the advantages of simple terrain modeling and small amount of calculation, and is easy to realize.

The invention relates to a dynamic terrain modeling method based on multi-resolution volume element, belonging to the field of computer graphics and virtual reality technology. On the basis of the dynamic terrain modeling method based on the volume element, the method divides the movable terrain blocks into regular meshes with inconsistent resolutions according to the acuteness degree of the change, and allocates the volume element deformation quantity on the adjacent volume elements at the bump region boundary, and finally adopts a corrosion arithmetic to carry out smooth treatment of the images. Compared with the prior art, the method can focus the terrain edge change details and effectively simplify the model when carrying out the large-scale dynamic terrain modeling, meets the correctness and trueness requirements of the model, achieves the object of lightening the system burden, and has effects of dynamically and effectively generating the terrain model in real-time and carrying out the real-time interaction with the simulation system.

The invention belongs to the field of remote sensing geology, and particularly discloses a method of searching for a potential ultra-large sandstone uranium deposit based on a remote sensing image. The method is implemented by the following steps: 1, terrain modeling is carried out by utilizing DEM data, and a region with an inclined unidirectionally terrain is searched for; 2, multi-spectral remote sensing data is used for performing river channel or ancient river channel interpretation on the inclined unidirectionally region interpreted in the step 1, and a region with gathered river channels is further searched for; 3, a source region is searched for to an upstream region along the river channels; 4, lithological and alteration mapping is carried out in the source region by utilizing the multi-spectral remote sensing data, and the rock type of the source region and the area of an alteration region are determined; and 5, the source region is a region with peraluminous granite and a wide alteration range, and a region with a gathered water body in a downstream region is judged to be a forming region of the potential ultra-large sandstone uranium deposit. The method has the following beneficial effects: the evaluation work of the uranium deposit can be carried out without limitation of regions and national boundaries.

The invention discloses a terrain steep ridge line information fusion method for regular grid DEM construction. The method comprises the following steps: S1, determining the minimum height differenceof regional steep ridge lines, and then determining the grid size of a target regular grid DEM; S2, deviating an elevation point on the steep ridge line, namely, deviating the elevation point fallingon the steep ridge line by a certain distance towards one side of the steep ridge line; S3, performing iterative encryption in a certain range of the steep ridge line to generate elevation points; andS4, constructing a regular grid DEM. According to the method, two key technical links of terrain steep ridge line elevation node offset and encryption generation considering virtual elevation sampling points around the steep ridge line are adopted, and the problem of form distortion caused by the terrain steep ridge line in high-precision terrain modeling can be effectively solved.

The invention discloses a virtual terrain modeling method based on linear interpolation, and relates to the technical field of computer simulation. At present, virtual terrain generation can not be compatible with speed and accuracy. The technical scheme comprises the following steps that: 1) setting a threshold value T; 2) selecting a grid cell, and calculating the variance Var of an elevation value; 3) judging the threshold value T and the variance Var, if the threshold value is large, jumping to 4), and otherwise, jumping to 5); 4) adopting a bilinear polynomial to carry out interpolation calculation, and establishing the terrain structure of a current grid; 5) adopting a bicubic polynomial to carry out terrain interpolation calculation, and establishing the terrain structure of the current grid; and 6) calculating all cells, and finishing terrain modeling based on a regular grid. The technical scheme is compatible with speed and accuracy, the flatness of the grid terrain is judged,different interpolation models are selected, the bilinear polynomial interpolation is adopted in the grid with the flat terrain to guarantee modeling speed, and the simulation accuracy of an area with large terrain fluctuation is improved through the bicubic polynomial.

The invention relates to a real terrain modeling and toxic gas diffusion simulation method. The method comprises the following steps: acquiring digital geographic data; determining the range of a computational domain according to the selected longitude and latitude information; acquiring a three-dimensional altitude coordinate in a computational domain, and converting the three-dimensional coordinate into a space coordinate; creating points, lines and surfaces through modeling software to obtain a real terrain surface, and constructing a computational domain surface according to the real terrain surface; constructing a computational domain body according to the constructed computational domain surface; carrying out grid division on the computational domain body through a DesignModeler andANSYS meshing software, and carrying out grid division on the computational domain body through ANSYS meshing software; and importing the grid file after grid division into the FLUENT, and observing the leakage influence range and the concentration distribution by checking the concentration cloud atlas of each species. According to the method, topographic data and software for simulating leakage and diffusion of the gas under the complex topography are easy to obtain, operation is easy and quick, a proper simulation domain can be established quickly, a high-quality grid can be established, anddiffusion of the gas under various conditions can be simulated effectively and accurately.

The invention discloses an image data storage method and system, and an image data reading method and system. The storage method comprises the following steps: establishing a rectangular coordinate system in a file in the horizontal direction and the vertical direction of image data, wherein the coordinates of the image data in the rectangular coordinate system use pixels as units; carrying out blocking of the image data in the rectangular coordinate system according to the coordinates to obtain image blocks; creating a pyramid according to the original image data, carrying out lossless compression on the image blocks, and carrying out lossy compression on the pyramid; and writing the compressed image blocks and the compressed pyramid into the file in the form of key-value storage. The image data storage method and system, and the image data reading method and system provided by the invention have the advantages that the lossless compression and the lossy compression are respectively carried out the original image data and the pyramid, so that hardware space is saved, the reading efficiency is high, multi-channel storage is achieved, the image data with different channels and different pixel storage sizes can be stored and read, and wide application prospects in satellite imaging, digital terrain modeling and engineering imaging are achieved.

The invention discloses a riverway type reservoir underwater terrain modeling method independent of measured data. Based on the publicly acquired DEM and reservoir distribution data, the rapid reconstruction of the underwater terrain of the reservoir can be realized. According to the method, known elevation information of upstream and downstream of a reservoir is utilized to speculate the longitudinal section of a river channel in a reservoir area, the longitudinal section is used as a terrain skeleton to generate a series of river channel cross sections, and known elevation information of twosides of the reservoir is utilized to speculate elevation information of underwater areas of the river channel cross sections. And finally, the method includes generating the underwater terrain of the reservoir based on the elevation prediction point of the reservoir area. The method is independent of field measured data, can quickly reconstruct the underwater topography of the reservoir, can beapplied to dynamic change monitoring of the reservoir capacity of the large-area-scale reservoir, and can provide method support for hydrology and water resource science research, reservoir information supervision and the like under the global change background.