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groundSurface

Add surface to tracking scenario

Description

surface = groundSurface(sc) adds a GroundSurface object, surface, to the tracking scenario sc.

example

surface = groundSurface(sc,Name=Value) specifies properties of the created GroundSurface object using one or more name-value arguments. For example, groundSurface(sc,ReferenceHeight=10) specifies the reference height of the ground surface as 10 meters. Unspecified properties take default values.

Examples

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Create a mesh grid that spans from -1000 meters to 1000 meters in both the x- and y-directions.

[x,y] = meshgrid(linspace(-1000,1000,500));

Specify the height for each mesh grid point.

z = 200*cos(x*pi/2000).*cos(y*pi/2000);

Create a tracking scenario and add a ground surface object to the tracking scenario. Specify the boundary of the surface area.

scene = trackingScenario;
surface = groundSurface(scene,Terrain=z,Boundary=[-1e3 1e3; -1e3 1e3])
surface = 
  GroundSurface with properties:

            Terrain: [500x500 double]
    ReferenceHeight: 0
           Boundary: [2x2 double]

Note that the SurfaceManager property of the tracking scenario now contains the created GroundSurface object.

manager = scene.SurfaceManager
manager = 
  SurfaceManager with properties:

    UseOcclusion: 1
        Surfaces: [1x1 fusion.scenario.GroundSurface]

manager.Surfaces
ans = 
  GroundSurface with properties:

            Terrain: [500x500 double]
    ReferenceHeight: 0
           Boundary: [2x2 double]

Visualize the surface using the helperGetTerrainMap helper function, attached to this example.

xSamples = linspace(-1e3,1e3,100);
ySamples = linspace(-1e3,1e3,100);
helperGetTerrainMap(surface,xSamples,ySamples);
xlabel("x (m)")
ylabel("y (m)")
zlabel("Height (m)")

Figure contains an axes object. The axes object contains an object of type surface.

Create a tracking scenario and specify its IsEarthCentered property as true.

scene = trackingScenario(IsEarthCentered=true);

Add a ground surface based on a DTED file, covering from 6 to 7 degrees in latitude and from 1 to 2 degrees in longitude.

terrain = "n06.dt0";
boundary = [6 7; % Latitude in degrees
            1 2]; % Longitude in degrees
surface = groundSurface(scene,Terrain=terrain,Boundary=boundary);

Sample the area using a 100-by-100 grid map.

samples = 100;
latitudes = linspace(6,7,samples);
longitudes = linspace(1,2,samples);
positions = [latitudes; longitudes];

Plot the terrain using the helperGetTerrrainMap helper function, attached to this example.

helperGetTerrainMap(surface,latitudes,longitudes);
xlabel("Latitude (Degrees)");
ylabel("Longitude (Degrees)");
zlabel("Height (Meters)");

Figure contains an axes object. The axes object contains an object of type surface.

Input Arguments

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Tracking scenario, specified as a trackingScenario object.

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

Example: surface = groundSurface(sc,ReferenceHeight=10)

Terrain data for the surface, specified as an M-by-N real-valued matrix, or a string scalar specifying a Digital Terrain Elevation Data (DTED) file name.

  • M-by-N real-valued matrix — The matrix values represent the height data of an area defined by the Boundary property of the ground surface object. The object extends the height data in the matrix to the area. The object automatically fills heights of unspecified points using linear interpolation. M and N must both be greater than 3.

  • String scalar or character vector specifying DTED file name — To use this option, you must specify the IsEarthCentered property of the tracking scenario as true. In this case, the object specifies the terrain heights for the area using those defined in the DTED file. The ground surface object automatically fills unspecified data in the DTED file using linear interpolation. If you want to use only a part of the terrain defined in the DTED file, specify the Boundary property as your desired subset of the terrain area defined in the DTED file. Otherwise, specify the Boundary property as the whole area defined in the DTED file.

Data Types: single | double | char

Boundary of the surface, specified as a 2-by-2 matrix of real values with the form [xmin xmax; ymin ymax]. When the IsEarthCentered property of tracking scenario object is specified as:

  • false — Specify xmin, xmax, ymin ymax, in meters, as Cartesian coordinates in the reference frame of the scenario, where xmin < xmax, and ymin < ymax

  • true — Specify xmin and xmax as the minimum and maximum latitudes of the geodetic frame in degrees, where xmin < xmax. Specify ymin and ymax as the minimum and maximum longitudes of the geodetic frame in degrees. If ymax < ymin, the object wraps ymax to ymax + 360.

Data Types: single | double

Reference height of the terrain data, specified as a scalar in meters. Specify the terrain data relative to this reference height.

Data Types: single | double

Output Arguments

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Ground surface, returned as a GroundSurface object.

Version History

Introduced in R2022a