Main Content

laneBoundaries

Get lane boundaries relative to host vehicle from RoadRunner Scenario

Since R2023a

Description

lbdrys = laneBoundaries(sensorSim,sensorID) gets the lane boundaries lbdrys of the lane in which the vehicle actor hosting the sensor specified by sensorID, is traveling. The lane boundaries are in the coordinate system of the host vehicle. The SensorSimulation object sensorSim specifies the RoadRunner scenario that contains the host vehicle actor.

Note

If you modify the RoadRunner scene after creating the SensorSimulation object, you must follow these steps for the changes to reflect correctly in MATLAB®:

  • Save and close RoadRunner.

  • Clear the ScenarioSimulation object from the MATLAB workspace.

  • Reopen the RoadRunner scenario.

  • Recreate the ScenarioSimulation object and the SensorSimulation objects.

example

lbdrys = laneBoundaries(sensorSim,sensorID,Name=Value) specifies additional options using one or more name-value arguments.

Examples

collapse all

Define sensor models in MATLAB®, and add them to vehicle actors in a RoadRunner Scenario. Then, obtain ground truth measurements from RoadRunner Scenario, process them into detections for visualization.

Set Up RoadRunner Scenario — MATLAB Interface

Configure your RoadRunner installation and project folder properties. Open the RoadRunner app.

rrInstallationPath = "C:\Program Files\RoadRunner R2024a\bin\win64";
rrProjectPath = "D:\RR\TestProjects";

s = settings;
s.roadrunner.application.InstallationFolder.PersonalValue = rrInstallationPath;
rrApp = roadrunner(rrProjectPath);

To open the scenario this example uses, you must add the TrajectoryCutIn-longRun.rrscenario file from the example folder to your RoadRunner project folder. Then, open the scenario.

copyfile("TrajectoryCutIn-longRun.rrscenario",fullfile(rrProjectPath,"Scenarios/"))
openScenario(rrApp,"TrajectoryCutIn-longRun")

Create a ScenarioSimulation object to connect MATLAB to the RoadRunner Scenario simulation and set the step size.

scenarioSim = createSimulation(rrApp);
Connection status: 1
Connected to RoadRunner Scenario server on localhost:60730, with client id {761e01bc-376c-4b4b-8ffa-aa1490d7438d}
stepSize = 0.1;
set(scenarioSim,"StepSize",stepSize);

Create a SensorSimulation object to control the sensor configuration for the RoadRunner Scenario simulation.

sensorSim = get(scenarioSim,"SensorSimulation");

To use the GPU on your device for supporting hardware accelerated raytracing, specify the UseGPU property of the SensorSimulation object to on. This enables supported sensors like lidars to use GPU for raytracing.

sensorSim.UseGPU = "on";

If you modify the RoadRunner scene after creating the SensorSimulation object, you must follow these steps for the changes to reflect correctly in MATLAB:

  • Save and close RoadRunner application.

  • Clear the ScenarioSimulation object from the MATLAB workspace.

  • Reopen the RoadRunner scenario.

  • Recreate the ScenarioSimulation object and the SensorSimulation object.

Configure Sensors and Add to RoadRunner Scenario

Configure sensor models for vision, radar and lidar sensors to add to the ego vehicle using visionDetectionGenerator, drivingRadarDataGenerator and lidarPointCloudGenerator objects. Specify unique IDs for each sensor.

visionSensor = visionDetectionGenerator(SensorIndex=1, ...
            SensorLocation=[2.4 0], MaxRange=50, ...
            DetectorOutput="Lanes and objects", ...
            UpdateInterval=stepSize);

radarSensor = drivingRadarDataGenerator(SensorIndex=2,...
    MountingLocation=[1.8 0 0.2], FieldOfView=[80 5],...
    AzimuthResolution=1,UpdateRate=1/stepSize);

lidarSensor = lidarPointCloudGenerator(SensorIndex=3,UpdateInterval=stepSize);

Add the sensor to the ego vehicle actor in the RoadRunner scenario. Specify the Actor ID property for the vehicle.

egoVehicleID = 1;
addSensors(sensorSim,{visionSensor,radarSensor,lidarSensor},egoVehicleID);

Simulate RoadRunner Scenario and Visualize Sensor Data

To visualize sensor data at each time-step of the simulation, add an observer to the RoadRunner scenario.

The helperSensorObserver system object implements the observer behavior. At the first timestep, the system object initializes the bird's-eye-plot for visualization, Then, at each time step, the system object:

  1. Retrieves target poses in the sensor range using the targetPoses function.

  2. Processes the target poses into detections using the sensor models.

  3. Visualizes detections and ground truth lane boundaries using birdsEyePlot.

observer = addObserver(scenarioSim,"VisualizeSensorData","helperSensorObserver");

Start the scenario.

set(scenarioSim,"SimulationCommand","Start");

Helper Functions

helperSetupBEP function creates a bird's-eye-plot and configures all the plotters for visualization.

helperPlotLaneBoundaries function plots the lane boundaries on the birds'eye-plot.

helperSensorObserver system object implements the visualization of sensor data during the RoadRunner scenario simulation.

type("helperSensorObserver.m")
classdef helperSensorObserver < matlab.System

    properties(Access=private)
        currSimTime
        scenarioSimObj
        sensorSimObj
        visionSensor
        radarSensor
        lidarSensor
        visionDetPlotter
        radarDetPlotter
        pcPlotter
        lbGTPlotter
        lbDetPlotter
        bepAxes
    end

    methods
        % Constructor
        function obj = helperSensorObserver()
        end
    end

    methods(Access=protected)

        function interface = getInterfaceImpl(~)
            import matlab.system.interface.*;
            interface = ActorInterface;
        end
        
        % Get ScenarioSimulation and SensorSimulation objects, set up Bird's-Eye-Plot
        function setupImpl(obj)
            obj.scenarioSimObj = Simulink.ScenarioSimulation.find('ScenarioSimulation','SystemObject',obj);
            obj.sensorSimObj = obj.scenarioSimObj.get('SensorSimulation');
            
            obj.visionSensor = evalin("base","visionSensor");
            obj.radarSensor = evalin("base","radarSensor");
            obj.lidarSensor = evalin("base","lidarSensor");

            [obj.visionDetPlotter,obj.radarDetPlotter,obj.pcPlotter,obj.lbGTPlotter,obj.lbDetPlotter,obj.bepAxes] = helperSetupBEP(obj.visionSensor,obj.radarSensor);
            legend(obj.bepAxes,"show")

            obj.currSimTime = 0;
        end

        function releaseImpl(obj)
            obj.lidarSensor.release;
            obj.radarSensor.release;
            obj.visionSensor.release;
        end

        function stepImpl(obj)
            % Get current Simulation Time
            obj.currSimTime = obj.scenarioSimObj.get("SimulationTime");
            
            % Get ground truth target poses and lane boundaries from the sensor
            tgtPoses1 = targetPoses(obj.sensorSimObj,1);
            tgtPoses2 = targetPoses(obj.sensorSimObj,2);
            gTruthLbs = laneBoundaries(obj.sensorSimObj,1,OutputOption="EgoAdjacentLanes",inHostCoordinate=true);
            
            if ~isempty(gTruthLbs)
                
                % Get detections from vision and radar sensors
                [visionDets,numVisionDets,visionDetsValid,lbDets,numLbDets,lbDetsValid] = obj.visionSensor(tgtPoses1,gTruthLbs,obj.currSimTime);
                [radarDets,numRadarDets,radarDetsValid] = obj.radarSensor(tgtPoses2,obj.currSimTime);
        
                % Get point cloud from lidar sensor
                [ptCloud,ptCloudValid] = obj.lidarSensor();
        
                % Plot ground-truth and detected lane boundaries
                helperPlotLaneBoundaries(obj.lbGTPlotter,gTruthLbs)
               
                
                % Plot vision and radar detections
                if visionDetsValid
                    detPos = cellfun(@(d)d.Measurement(1:2),visionDets,UniformOutput=false);
                    detPos = vertcat(zeros(0,2),cell2mat(detPos')');
                    plotDetection(obj.visionDetPlotter,detPos)
                end
        
                if lbDetsValid
                    plotLaneBoundary(obj.lbDetPlotter,vertcat(lbDets.LaneBoundaries))
                end
        
                if radarDetsValid
                    detPos = cellfun(@(d)d.Measurement(1:2),radarDets,UniformOutput=false);
                    detPos = vertcat(zeros(0,2),cell2mat(detPos')');
                    plotDetection(obj.radarDetPlotter,detPos)
                end
        
                % Plot lidar point cloud
                if ptCloudValid
                    plotPointCloud(obj.pcPlotter,ptCloud);
                end
            end
        
        end  
    end

end

Input Arguments

collapse all

Sensor simulation object, specified as a SensorSimulation object. The sensor simulation object must correspond to the desired scenario created in RoadRunner Scenario.

Unique index of the sensor in the RoadRunner Scenario, specified as a positive scalar. This must be same as the SensorIndex property of the detection generator object which corresponds to the desired sensor.

Name-Value Arguments

collapse all

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.

Example: lbdrys = laneBoundaries(sensorSim,1,OutputOption="EgoAdjacentLanes") returns the boundaries for the current and adjacent lanes to the vehicle actor hosting sensor 1.

Lane boundaries to output, specified as one of these options:

  • "EgoLane" — The function returns the boundaries for the lane in which the host vehicle actor is traveling.

  • "EgoAdjacentLanes" — The function returns the boundaries for the adjacent left and right lanes along with the lane in which host vehicle actor is traveling.

  • "AllLanes" — The function returns the boundaries for all lanes on the road.

Enable the lane boundaries to be returned in host vehicle coordinates, specified as a logical 1 (true) or 0 (false). Specify this argument as false or 0 to return the lane boundaries in the world coordinates of the RoadRunner scenario.

Output Arguments

collapse all

Lane boundaries, returned as an array of lane boundary structures. This table shows the fields for each structure.

FieldDescription

Coordinates

Lane boundary coordinates, returned as a real-valued N-by-3 matrix, where N is the number of lane boundary coordinates. Lane boundary coordinates define the position of points on the boundary at returned longitudinal distances away from the ego vehicle, along the center of the road.

  • In MATLAB, specify these distances by using the 'XDistance' name-value pair argument of the laneBoundaries function.

  • In Simulink®, specify these distances by using the Distances from ego vehicle for computing boundaries (m) parameter of the Scenario Reader block or the Distance from parent for computing lane boundaries parameter of the Simulation 3D Vision Detection Generator block.

This matrix also includes the boundary coordinates at zero distance from the ego vehicle. These coordinates are to the left and right of the ego vehicle origin, which is located under the center of the rear axle. Units are in meters.

Curvature

Lane boundary curvature at each row of the Coordinates matrix, returned as a real-valued N-by-1 vector. N is the number of lane boundary coordinates. Units are in radians per meter.

CurvatureDerivative

Derivative of lane boundary curvature at each row of the Coordinates matrix, returned as a real-valued N-by-1 vector. N is the number of lane boundary coordinates. Units are in radians per square meter.

HeadingAngle

Initial lane boundary heading angle, returned as a real scalar. The heading angle of the lane boundary is relative to the ego vehicle heading. Units are in degrees.

LateralOffset

Lateral offset of the ego vehicle position from the lane boundary, returned as a real scalar. An offset to a lane boundary to the left of the ego vehicle is positive. An offset to the right of the ego vehicle is negative. Units are in meters. In this image, the ego vehicle is offset 1.5 meters from the left lane and 2.1 meters from the right lane.

Ego vehicle in a driving lane

BoundaryType

Type of lane boundary marking, returned as one of these values:

  • 'Unmarked' — No physical lane marker exists

  • 'Solid' — Single unbroken line

  • 'Dashed' — Single line of dashed lane markers

  • 'DoubleSolid' — Two unbroken lines

  • 'DoubleDashed' — Two dashed lines

  • 'SolidDashed' — Solid line on the left and a dashed line on the right

  • 'DashedSolid' — Dashed line on the left and a solid line on the right

Strength

Saturation strength of the lane boundary marking, returned as a real scalar from 0 to 1. A value of 0 corresponds to a marking whose color is fully unsaturated. The marking is gray. A value of 1 corresponds to a marking whose color is fully saturated.

Width

Lane boundary width, returned as a positive real scalar. In a double-line lane marker, the same width is used for both lines and for the space between lines. Units are in meters.

Length

Length of dash in dashed lines, returned as a positive real scalar. In a double-line lane marker, the same length is used for both lines.

Space

Length of space between dashes in dashed lines, returned as a positive real scalar. In a dashed double-line lane marker, the same space is used for both lines.

Version History

Introduced in R2023a