Observation_Log

This section describes the parameters and outputs of the Observation_Log observer.

Parameterization

Following parameters are supported:

Parameter	Type	Description
OutputFilename	String	Name of the output file (normally simulationOutput.xml)
LoggingCyclicsToCsv	Bool	If true, cyclics are written an additional file (one CSV file per run)
LoggingGroup_<NAME>	StringVector	Defines which columns belong to the logging group named NAME
LoggingGroups	StringVector	Defines active logging groups

The columns, defined by the LoggingGroup_<NAME> correspond to cyclic data entries written by the world and other components. Cyclics are named data values of a single agent during a specific timestep. Simulation components including agent components can write this values into the DataBuffer component using the PublisherInterface. The Observation_Log can then read this values and write them into the output.

The world publishes the following cyclics (see source of AgentNetwork.cpp):

Cyclics	Type	Unit	Description
XPosition	Double	m	Position x of the reference point (in world coordinates)
YPosition	Double	m	Position y of the reference point (in world coordinates)
VelocityEgo	Double	m/s	Absolute velocity (length of the velocity vector) at the reference point (including spin caused by YawRate)
AccelerationEgo	Double	m/s²	Longitudinal acceleration (including angular acceleration) at the reference point. Longitudinal refers to the angle of the vehicle regardless of the curvature of the road it is on.
YawAngle	Double	rad	Yaw angle w.r.t. x-axis
YawRate	Double	rad/s	Yaw rate of the agent
SteeringAngle	Double	rad	Steering wheel angle
TotalDistanceTraveled	Double	m	Total traveled distance of all agents
PositionRoute*	Double	m	Position of the agent’s front center in road’s s coordinate (distance to the start of the road)
TCoordinate*	Double	m	Position of the agent’s front center in lane’s t coordinate (distance to the middle of the lane respecting intended driving direction)
Lane*	Integer		Id of the lane
Road*	String		OpenDRIVE id of the road on which the agent is on (i.e. the front center).
SecondaryLanes*	IntegerVector		List of secondary lanes on a specific road
AgentInFront*	Integer		Id of the next object on the agent’s route

The longitudinal driver publishes the following cyclics (see source of longitudinalDriver.cpp):

Cyclics	Type	Description
AccelerationPedalPosition	Double	Position of the acceleration pedal position in percent
BrakePedalPosition	Double	Position of the brake pedal position in percent
Gear	Integer	Current gear position

The component Action_SecondaryDriverTasks publishes the following cyclics (see source of secondaryDriverTasks.cpp):

Cyclics	Type	Description
BrakeLight	Boolean	True if BrakeLight is on
IndicatorState	Enum	State of the turning indicator (left, center/off, right)
LightStatus	Enum	State of the headlight (off, low beam, fog light, high beam, flash)

The component AgentUpdater publishes the following cyclics (see source of agentUpdaterImpl.cpp):

Cyclics	Type	Description
LongitudinalController	String	Component that is active for longitudinal control
LateralController	String	Component that is active for lateral control

The component Dynamics_RegularDriving publishes the following cyclics (see source of regularDriving.cpp):

Cyclics	Type	Unit	Description
EngineMoment	Double	Nm	Torque of the engine
SteeringAngle	Double	rad	Angle of the steering wheel

The component Sensor_Driver publishes the following cyclics (see source of sensor_driverImpl.cpp):

Cyclics	Type	Description
AgentInFront	Integer	Id of the agent infront

The component Sensor_OSI publishes the following cyclics (see source of sensorCar2X.cpp):

Cyclics	Type	Description
DetectedAgents	String	List of ids of detected agents
VisibleAgents	String	List of ids of visible agents

Wildcards in LoggingGroup definitions

It is possible to use the wildcard character * in a LoggingGroup_<NAME> entry.

The wildcard can be used only once per column reference.

Example

      <Library>Observation_Log</Library>
      <Parameters>
        <String Key="OutputFilename" Value="simulationOutput.xml"/>
        <Bool Key="LoggingCyclicsToCsv" Value="false"/>
        <StringVector Key="LoggingGroup_Trace" Value="XPosition,YPosition,YawAngle"/>
        <StringVector Key="LoggingGroup_RoadPosition" Value="AgentInFront,Lane,PositionRoute,Road,TCoordinate"/>
        <StringVector Key="LoggingGroup_RoadPositionExtended" Value="SecondaryLanes"/>
        <StringVector Key="LoggingGroup_Sensor" Value="Sensor*_DetectedAgents,Sensor*_VisibleAgents"/>
        <StringVector Key="LoggingGroup_Vehicle" Value="AccelerationPedalPosition,BrakePedalPosition,EngineMoment,Gear,SteeringAngle,TotalDistanceTraveled,YawRate"/>
        <StringVector Key="LoggingGroup_Visualization" Value="AccelerationEgo,BrakeLight,IndicatorState,LightStatus,VelocityEgo"/>
        <StringVector Key="LoggingGroups" Value="Trace,Visualization,RoadPosition,Sensor"/>
      </Parameters>

Output Files

SimulationOutput

Every successful run (single experiment) generates a single file, normally called simulationOutput.xml (see :ref:’observationlog_parameterization’). The output can contain multiple invocations of the same configuration with different random seeds. For each invocation a RunResult is stored, which contains information about the agents and their parameters. As well as run specific events and parameters.

<SimulationOutput>
    <RunResults>
        <RunResult RunId="0">
            ...
        </RunResult>
        <RunResult RunId="1">
            ...
        </RunResult>
    </RunResults>
</SimulationOutput>

The RunResult consist out of the following parts:

• RunStatistics

• Events

• Agents

• Cyclics

RunStatistics

This section contains the RandomSeed and general statistics of the invocation.

Tag	Description
RandomSeed	Random seed used for this invocation
VisibilityDistance	Visibility distance of the world
StopReason	Displays the reason why the simulation stopped. Currently only due to time out.
StopTime	Currently not used and set to -1
EgoAccident	Flag which shows whether the ego agent was involved in an accident
TotalDistanceTraveled	Total traveled distance of all agents
EgoDistanceTraveled	Total traveled distance of ego vehicle only

Events

This section contains all events that occurred during the invocation. Event can either be triggered by an EventDetector, Manipulator or by certain vehicle components. They are used to track special behavior in the simulation.

Attribute	Description
Time	Time in ms when the event occurred.
Source	Name of the component which created the event. OpenSCENARIO, if triggered by an OpenSCENARIO condition.
Name	In case of an OpenSCENARIO event, a path expression Story/Act/Sequence/Maneuver/Event using the names of the corresponding tags as described in the OpenSCENARIO file. Otherwise determined by the triggering component.
TriggeringEntities	List of entity IDs triggering this event.
AffectedEntities	List of entity IDs affected by this event.
Parameters	List of generic key/value string pairs.

Important Events

Some of the Events are logged for other applications to use, for instance the openPASS Visualizer. These Events can be identified by their Name and are listed below:

Attribute	Description
TrafficLight	TrafficLight Events are triggered once a TrafficLightController changes the state of it’s Trafficlight bulbs. Parameters include the traffic_light_state and the opendrive_id which links to a dynamic signal in the scenery configuration. traffic_light_state is going to be used by the openPASS Visualizer. The initial state of the ThreeSignalsTrafficLight is posted too.

The change in the active component of longitudinal and/or lateral control is also logged as event with name “ActiveComponentChange”.

Agents

This section contains some information on how each agent is configured.

Attribute	Description
Id	Identification number
AgentTypeGroupName	The agent category. This can either be Ego, Scenario or Common
AgentTypeName	Name of the agent profile
VehicleModelType	Name of the vehicle model
DriverProfileName	Name of the driver profile

<Agent Id="0"
       AgentTypeGroupName="Ego"
       AgentTypeName="MiddleClassCarAgent"
       VehicleModelType="car_bmw_7"
       DriverProfileName="Regular">

The VehicleAttributes tag lists basic information of the vehicle parameters.

Attribute	Description
Width	Width of the vehicles bounding box
Length	Length of the vehicles bounding box
Height	Height of the vehicles bounding box
LongitudinalPivotOffset	Distance between center of the bounding box and reference point of the agent. Positive distances are closer to the front of the vehicle. Negative distances are closer to the rear of the vehicle.

The Components tag lists all instantiated components from the SystemProfile.

Attribute	Description
Type	Type of the component
Profile	Name of the component profile

The Sensors tag lists all sensors of the agent and their parameters.

Attribute	Description
Name	Name of the component
Model	Type of the sensor
MountingPosLongitudinal	Relative longitudinal position of the sensor in relation to the agent
MountingPosLateral	Relative lateral position of the sensor in relation to the agent
MountingPosHeight	Relative height of the sensor in relation to the agent
OrientationPitch	Pitch rotation of the sensor in relation to the agent
OrientationYaw	Yaw rotation of the sensor in relation to the agent
OpeningAngleH	Horizontal opening angle of the sensor
OpeningAngleV	Vertical opening angle of the sensor
DetectionRange	Range how far the sensor reaches in m

Note

Calculation of visual obstruction is currently supported only by the Geometric2D sensor. See SystemConfigBlueprint for configuration.

<Sensor Name="Geometric2DFront"
        Model="Geometric2D"
        MountingPosLongitudinal="0"
        MountingPosLateral="0"
        MountingPosHeight="0.5"
        OrientationPitch="0"
        OrientationYaw="0"
        OpeningAngleH="20"
        OpeningAngleV="-999"
        DetectionRange="300" />

Cyclics

If the parameter LoggingCyclicsToCsv is set to false, this section contains all logged parameters of the agents per time step. The tag header defines the layout of all samples. Each entry of the header consists of the agent id and the name of the logged value, in the form ID:SAMPLE_NAME. A sample contains all information for one specific time step. If an agent does not exist at the current time step, the value is ‘ ‘.

Example

In this example exist two agents with the ids 0 and 1. Two time steps were being tracked, one at 0 seconds and one at 100 ms. Agent 0 has a constant velocity of 30 m/s and starts at the position X: 100 and Y: 50. Agent 1 has a initial velocity of 40 m/s and starts at the position X: 200 and Y: 50.

<Cyclics>
    <Header>00:VelocityEgo, 00:XPosition, 00:YPosition, 00:YawAngle, 01:VelocityEgo, 01:XPosition, 01:YPosition, 01:YawAngle</Header>
    <Samples>
        <Sample Time="0">30, 100, 50, 0, 40, 200, 50, 0</Sample>
        <Sample Time="100">30, 103, 50, 0, 40, 204, 50, 0</Sample>
    </Samples>
</Cyclics>

If the parameter LoggingCyclicsToCsv is set to true, this section only contains a reference to the corresponding CSV file, e.g.

<Cyclics>
    <CyclicsFile>Cyclics_Run_000.csv</CyclicsFile>
</Cyclics>

For each invocation, the file number of the filename is incremented, starting with Cyclics_Run_000.csv.

Cyclics_Run_###

This file contains the samples as described in :ref:’observationlog_cyclics’, but with the time step as leading column.

Example

Timestep	00:VelocityEgo	00:XPosition	00:YPosition	00:YawAngle	01:VelocityEgo	01:XPosition	01:YPosition	01:YawAngle
0	30	100	50	0	40	200	50	0
100	30	103	50	0	40	204	50	0