trackerSensorSpec

Sensor specification for multi-target multi-sensor specification-based tracker

Since R2024b

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    Syntax

    spec = trackerSensorSpec(domain,category,subcategory)
    spec = trackerSensorSpec("custom")

    Description

    spec = trackerSensorSpec(domain,category,subcategory) creates a sensor specification based on the input application. You can use tab completion at each input argument to view the available applications. This hierarchy shows the list of prebuilt sensor specifications available in the toolbox.

    example

    spec = trackerSensorSpec("custom") creates a custom sensor specification. You can modify the custom sensor specification by defining its measurement model, detectability model, clutter model, and birth model. (since R2025a)

    example

    Examples

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    Open Live Script

    Create a sensor specification for a camera mounted on an ego vehicle.

    cameraSpec = trackerSensorSpec("automotive","camera","bounding-boxes")
    cameraSpec = 
  AutomotiveCameraBoxes with properties:

               ReferenceFrame: 'ego'                 
           MaxNumMeasurements: 64                    
             MountingLocation: [0 0 0]         m     
               MountingAngles: [0 1 0]         deg   
              EgoOriginHeight: 0.3             m     
                   Intrinsics: [3⨯3 double]          
                    ImageSize: [480 640]       pixels
                     MaxRange: 100             m     
               CenterAccuracy: 10              pixels
               HeightAccuracy: 10              pixels
                WidthAccuracy: 10              pixels
         DetectionProbability: 0.9                   
    NumFalsePositivesPerImage: 0.01                  
        NumNewTargetsPerImage: 0.01

    Specify the mounting location and angles, resolution, intrinsic matrix, maximum range, and height of the ego vehicle.

    cameraSpec.MountingLocation = [3.7920 0 1.1];
cameraSpec.MountingAngles = [0 1 0];
cameraSpec.ImageSize = [480 640];
cameraSpec.Intrinsics = [800         0        320
                           0       600        240
                           0         0         1];
cameraSpec.MaxRange = 80;
cameraSpec.EgoOriginHeight = 0.4;

    Create a target specification for a car. Then, use the sensor specification for the camera and the target specification for the car as inputs to the multiSensorTargetTracker function to create a JIPDA tracker.

    carSpec = trackerTargetSpec("automotive","car","highway-driving");
tracker = multiSensorTargetTracker(carSpec,cameraSpec,"jipda")
    tracker = 
  fusion.tracker.JIPDATracker with properties:

                TargetSpecifications: {[1×1 HighwayCar]}
                SensorSpecifications: {[1×1 AutomotiveCameraBoxes]}
              MaxMahalanobisDistance: 5
    ConfirmationExistenceProbability: 0.9000
        DeletionExistenceProbability: 0.1000

    Use the dataFormat function to determine the data format for the inputs required by the tracker.

    The camera requires bounding boxes in the image space.

    cameraData = dataFormat(cameraSpec)
    cameraData = struct with fields:
           Time: 0
    BoundingBox: [4×64 double]
    Open Live Script

    Create a specification for a marine radar. The radar of interest is on top of a stationary tower.

    radarPosition = [0;0;35]; % radar's relative position to the tower origin.
towerPosition = [3800;15200;110]; % tower origin location in scenario coordinate.
radarOrientation = [0 1 0;-1 0 0;0 0 1]; % radar's relative orientation to the tower origin.
towerOrientation = [-0.2 0.6 0.7;0.9 0.3 0;-0.2 0.7 -0.6]; % tower orientation in scenario coordinate.
marineRadarSpec = trackerSensorSpec("custom")
    marineRadarSpec = 
  CustomSensor with properties:

    MaxNumMeasurements: 32

      MeasurementModel: []
    DetectabilityModel: []
          ClutterModel: []
            BirthModel: []

          UpdateModels: 0

    Define the measurement, detectability, clutter, and birth model of the marine radar specification. For measurement, specify that the radar of interest reports the position in the scenario coordinates. 

    measurementModel = sensorMeasurementModel("position");
measurementModel.OriginPosition = zeros(3,1);
measurementModel.Orientation = eye(3);

    For detectability, specify that the radar detects targets within its field of view around a center beam.

    detectabilityModel = sensorDetectabilityModel("field-of-view");
detectabilityModel.AzimuthLimits = [-10 10];
detectabilityModel.ElevationLimits = [-15 15];
detectabilityModel.RangeLimits = [0 10000];
detectabilityModel.OriginPosition = cat(2,radarPosition,towerPosition);
detectabilityModel.Orientation = cat(3,radarOrientation,towerOrientation);
detectabilityModel.DetectionProbability = 0.95;

    For clutter, specify that the radar assumes a uniform Poisson clutter model, which assumes false measurements or noise (referred to as "clutter") in radar data are uniformly distributed across the observation space.

    clutterModel = sensorClutterModel("uniform-poisson");
clutterModel.ClutterDensity = 5e-9;

    For birth, specify that the radar assumes a uniform Poisson birth model, which assumes new targets can appear uniformly across the entire observation space.

    birthModel = sensorBirthModel("uniform-poisson");
birthModel.BirthDensity = 5e-9;

    Configure the marine radar specification using these models.

    marineRadarSpec.MeasurementModel = measurementModel;
marineRadarSpec.DetectabilityModel = detectabilityModel;
marineRadarSpec.ClutterModel = clutterModel;
marineRadarSpec.BirthModel = birthModel;

    To update the specification based on time or measurement, you can set the UpdateModels property to true and specify the ModelUpdateFcn function handle of the specification. For example, the following model update function allows you to update the radar center beam orientation with time, and update the position variance with measurement.

    marineRadarSpec.UpdateModels = true;
marineRadarSpec.ModelUpdateFcn = @updateRadarSpec;
function spec = updateRadarSpec(spec, data)
if ~isempty(data.Time)
    spec.DetectabilityModel.Orientation(:,:,1) = data.TimeVaryingModelData.BeamOrientation;
end
if ~isempty(data.MeasurementTime)
    spec.MeasurementModel.PositionVariance = data.MeasurementVaryingModelData.PositionVariance;
end
end

    Input Arguments

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    Sensor domain, specified as "aerospace", "automotive", or "custom" (since R2025a).

    Note

    When you specify the domain as "custom", do not specify the category and subcategory input arguments.

    Sensor category, specified as one of these values:

    • "radar" or "infrared" if the domain is "aerospace"

    • "radar", "camera" or "lidar" if the domain is "automotive"

    Sensor subcategory, specified as one of these values:

    • "monostatic", "bistatic" (since R2025a) or "direction-finder" if the domain is "aerospace" and the category is "radar"

    • "angle-only" if the domain is "aerospace" and the category is "infrared"

    • "clustered-points" if the domain is "automotive" and the category is "radar"

    • "bounding-boxes" if the domain is "automotive" and the category is "camera" or "lidar"

    Output Arguments

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    Sensor specification, returned as one of the objects in this table based on the input arguments.

    Input ArgumentsSensor Specification Object
    "aerospace","radar","monostatic"AerospaceMonostaticRadar
    "aerospace","radar","bistatic"AerospaceBistaticRadar (since R2025a)
    "aerospace","radar","direction-finder"AerospaceESMRadar
    "aerospace","infrared","angle-only"AerospaceAngleOnlyIR
    "automotive","radar","clustered-points"AutomotiveRadarClusteredPoints
    "automotive","camera","bounding-boxes"AutomotiveCameraBoxes
    "automotive","lidar","bounding-boxes"AutomotiveLidarBoxes
    "custom"CustomSensor (since R2025a)

    You can use this sensor specification object to define a tracker using the multiSensorTargetTracker function. You can use the dataFormat function on the spec object to determine the data format required by the tracker.

    Version History

    Introduced in R2024b

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    See Also

    Functions

    Objects

    Topics