birdsEyePlot

Plot detections, tracks, and sensor coverages around vehicle

Description

The birdsEyePlot object displays a bird's-eye plot of a 2-D driving scenario in the immediate vicinity of an ego vehicle. You can use this plot with sensors capable of detecting objects and lanes.

To display aspects of a driving scenario on a bird’s-eye plot:

1. Create a birdsEyePlot object.

2. Create plotters for the aspects of the driving scenario that you want to plot.

3. Use the plotters with their corresponding plot functions to display those aspects on the bird's-eye plot.

This table shows the plotter functions to use based on the driving scenario aspect that you want to plot.

Driving Scenario Aspect to Plot	Plotter Creation Function	Plotter Display Function
Sensor coverage areas	coverageAreaPlotter	plotCoverageArea
Sensor detections	detectionPlotter, rangeDetectionPlotter	plotDetection, plotRangeDetection
Lane boundaries	laneBoundaryPlotter	plotLaneBoundary
Lane markings	laneMarkingPlotter	plotLaneMarking, plotParkingLaneMarking
Object meshes	meshPlotter	plotMesh
Object outlines	outlinePlotter	plotOutline, plotBarrierOutline
Ego vehicle path	pathPlotter	plotPath
Point cloud	pointCloudPlotter	plotPointCloud
Object tracking results	trackPlotter	plotTrack

For an example of how to configure and use a bird's-eye plot, see Visualize Sensor Coverage, Detections, and Tracks.

Creation

Syntax

bep = birdsEyePlot

bep = birdsEyePlot(Name,Value)

Description

bep = birdsEyePlot creates a bird’s-eye plot in a new figure.

bep = birdsEyePlot(Name,Value) sets properties using one or more Name,Value pair arguments. For example, birdsEyePlot('XLimits',[0 60],'YLimits',[-20 20]) displays the area that is 60 meters in front of the ego vehicle and 20 meters to either side of the ego vehicle. Enclose each property name in quotes.

Properties

Parent — Axes on which to plot

axes handle

Axes on which to plot, specified as an axes handle. By default, the birdsEyePlot object uses the current axes handle, which is returned by the gca function.

Plotters — Plotters created for bird's-eye plot

array of plotter objects

Plotters created for the bird's-eye plot, specified as an array of plotter objects.

XLimits — X-axis range

real-valued vector of the form [X_min X_max]

X-axis range of the bird's-eye plot, in vehicle coordinates, specified as a real-valued vector of the form [X_min X_max]. Units are in meters. If you do not specify XLimits, then the plot uses the default values for the parent axes.

The X-axis is vertical and positive in the forward direction of the ego vehicle. The origin is at the center of the rear axle of the ego vehicle.

For more details on the coordinate system used in the bird's-eye plot, see Vehicle Coordinate System.

YLimits — Y-axis range

real-valued vector of the form [Y_min Y_max]

Y-axis range of the bird's-eye plot, in vehicle coordinates, specified as a real-valued vector of the form [Y_min Y_max]. Units are in meters. If you do not specify YLimits, then the plot uses the default values for the parent axes.

The Y-axis runs horizontally and is positive to the left of the ego vehicle, as viewed when facing forward. The origin is at the center of the rear axle of the ego vehicle.

For more details on the coordinate system used in the birdsEyePlot object, see Vehicle Coordinate System.

Object Functions

Plotter Creation

coverageAreaPlotter	Coverage area plotter for bird's-eye plot
detectionPlotter	Detection plotter for bird's-eye plot
laneBoundaryPlotter	Lane boundary plotter for bird's-eye plot
laneMarkingPlotter	Lane marking plotter for bird's-eye plot
meshPlotter	Mesh plotter for bird's-eye plot
outlinePlotter	Outline plotter for bird's-eye plot
pathPlotter	Path plotter for bird's-eye plot
pointCloudPlotter	Point cloud plotter for bird's-eye plot
trackPlotter	Track plotter for bird's-eye plot

Plotter Display

plotCoverageArea	Display sensor coverage area on bird's-eye plot
plotDetection	Display object detections on bird's-eye plot
plotLaneBoundary	Display lane boundaries on bird’s-eye plot
plotLaneMarking	Display lane markings on bird’s-eye plot
plotParkingLaneMarking	Display parking lane markings on bird’s-eye plot
plotMesh	Display object meshes on bird's-eye plot
plotOutline	Display object outlines on bird's-eye plot
plotPath	Display actor paths on bird’s-eye plot
plotPointCloud	Display generated point cloud on bird's-eye plot
plotTrack	Display object tracks on bird's-eye plot

Plotter Utilities

clearData	Clear data from specific plotter of bird’s-eye plot
clearPlotterData	Clear data from bird’s-eye plot
findPlotter	Find plotters associated with bird’s-eye plot

Examples

Create and Display a Bird's-Eye Plot

Create a bird's-eye plot with an x-axis range from 0 to 90 meters and a y-axis range from –35 to 35 meters.

bep = birdsEyePlot('XLim',[0 90],'YLim',[-35 35]);

Display a coverage area with a 35-degree field of view and a 60-meter range.

caPlotter = coverageAreaPlotter(bep,'DisplayName','Radar coverage area');
mountPosition = [1 0];
range = 60;
orientation = 0;
fieldOfView = 35;
plotCoverageArea(caPlotter,mountPosition,range,orientation,fieldOfView);

Display radar detections with coordinates at (30, –5), (50, –10), and (40, 7).

radarPlotter = detectionPlotter(bep,'DisplayName','Radar detections');
plotDetection(radarPlotter,[30 -5; 50 -10; 40 7]);

Create Bird's-Eye Plot with Coverage Area and Detection Plotters

Create a bird's-eye plot with an x-axis range of 0 to 90 meters and a y-axis range from –35 to 35 meters. Configure the plot to include a radar coverage area plotter and a detection plotter. Set the display names of these plotters.

bep = birdsEyePlot('XLim',[0 90],'YLim',[-35 35]);
coverageAreaPlotter(bep,'DisplayName','Radar coverage area');
detectionPlotter(bep,'DisplayName','Radar detections');

Use findPlotter to locate the plotters by their display names.

caPlotter = findPlotter(bep,'DisplayName','Radar coverage area');
radarPlotter = findPlotter(bep,'DisplayName','Radar detections');

Plot the coverage area and detected objects.

plotCoverageArea(caPlotter,[1 0],30,0,35);
plotDetection(radarPlotter,[30 5; 30 -10; 30 15]);

Clear data from the plot.

clearPlotterData(bep);

Limitations

The rectangle-zoom feature, where you draw a rectangle to zoom in on a section of a figure, does not work in bird's-eye plot figures.

More About

Vehicle Coordinate System

The birdsEyePlot uses the vehicle coordinate system (X_V, Y_V), where:

• The X_V-axis points forward from the ego vehicle.

• The Y_V-axis points to the left, as viewed when facing forward.

The origin is at the center of rotation of the ego vehicle. This point is on the road surface, beneath the center of the rear axle of the ego vehicle.

For more details about the vehicle coordinate system, see Coordinate Systems in Automated Driving Toolbox.

Version History

Introduced in R2017a