SensorDriver

This module collects and distributes data from the WorldInterface and AgentInterface concerning the own vehicle, mesoscopic information and surrounding object. It creates a data struct to store the world and agent data of the own vehicle, mesoscopic information, other objects and surrounding vehicles. Own vehicle data examples are ID, velocity, heading angle, yaw angle, lateral/longitudinal position, … for the ego vehicle. Mesoscopic information are for example number of lanes, visibility distance, … and lane specifics like lane curvature, lane width, … Surrounding object and other object data (vehicles or static objects) are for example brake light status, velocity (lateral & longitudinal), indicator state, … for each area of interest. Overview of the connections for information distribution is shown in Fig. 59.

Fig. 59 Connections for information distribution

Overview of the module’s functionalities

This module gathers the ground truth informations from the simulation framework which are going to be perceived by SCM. It serves as a central connection for all get-functions of the WorldInterface and AgentInterface which updates the external informations of the agent at the beginning of every single time step. Internal informations of the agent have to be transfered from other declared modules by different signals. All these gathered informatons by Updateinput-function of SCM will be internally sent to the submodule InformationAcquisition. Fig. 60 illustrates the distribution of collected informations from WorldInterface and AgentInterface to other Modules and their submodules. The module contains structs which are divided into five different parts to store and transport the world and agent data of the own vehicle, mesoscopic informations, other objects, lanes and surrounding vehicles:

Fig. 60 Information distribution between modules

Components of the module

The information collected by SensorDriver consist of generally four different data structs (Fig. 61):

OwnVehicleStates includes all information about the vehicle of the driver (e.g. speed, acceleration, …)
MesoscopicInformation includes information about the traffic environment concerning dynamic objects on the mesoscopic traffic level (e.g. mean velocity of a lane …)
InfrastructureInformation includes information about the static environment (e.g. traffic signs, lane markings, …)
SurroundingObjects includes information about objects in all AreasOfInterest (see Gaze Control)

OwnVehicleStates

The Information of the own vehicle are based on the following general struct OwnVehicleInformation :

Variable	Meaning	Default value
velocity	Velocity of agent	-999
acceleration	Acceleration of agent	-999
lateralPosition	t-coordinate	-999
heading	Heading relative to lane	-999
steeringWheelAngle	Angle of the steering wheel	-999
isCrossingLanes	Wether the agent touches multiple neighbouring lanes	false
distanceToLaneBoundaryLeft	Distance between the left front point and the left boundary of the lane it is in	-999
distanceToLaneBoundaryRight	Distance between the right front point and the right boundary of the lane it is in	-999
collision	Wether this agent has collided with another object	false

In SCM this struct is extended by the following struct OwnVehicleInformationSCM :

Variable	Meaning	Default value
id	Id of the agent	-1
mainLaneId	Id of the mainLane, i.e. where the middle of the reference point is	-99
longitudinalVelocity	Velocity in direction of s	-999
lateralVelocity	Velocity in direction of t	-999
longitudinalPosition	Longitudinal position from start of read [m]	-999
soundPressureLevelInterior	Sound pressure level of the own vehicle interior noise	-999
forcedLaneChangeStartTrigger	Forced lane change action from manipulator	none

MesoscopicInformation

The struct MesoscopicInformationSCM contains mesoscopic information like information about surrounding lanes.

The general structure is shown in the following table.

Variable	Meaning	Default value
laneLeftLeft	struct LaneInformationMesoscopicSCM - Data about the lane two lanes left of the mainLane (in driving direction)
laneLeft	struct LaneInformationMesoscopicSCM - Data about the lane to the left of the mainLane (in driving direction)
laneEgo	struct LaneInformationMesoscopicSCM - Data about the lane where the middle of the front of the agent is (e.g. mainLane)
laneRight	struct LaneInformationMesoscopicSCM - Data about the lane to the right of the mainLane (in driving direction)
laneRightRight	struct LaneInformationMesoscopicSCM - Data about the lane two lanes right of the mainLane (in driving direction)

The basis for the respective variables is the following struct LaneInformationMesoscopicSCM:

Variable	Meaning	Default value
meanVelocity	Mean velocity of all other agents on this lane inside visibility distance	-999

InfrastructureInformation

The InfrastructureInformation consist of TrafficRuleInformation and GeometryInformation.

TrafficRuleInformation

The struct TrafficRuleInformationSCM contains infrastructure information of surrounding lanes that are used to establish traffic rules.

The general structure is shown in the following table.

Variable	Meaning	Default value
laneLeftLeft	struct LaneInformationTrafficRulesSCM - Data about the lane two lanes left of the mainLane (in driving direction)
laneLeft	struct LaneInformationTrafficRulesSCM - Data about the lane to the left of the mainLane (in driving direction)
laneEgo	struct LaneInformationTrafficRulesSCM - Data about the lane where the middle of the front of the agent is (e.g. mainLane)
laneRight	struct LaneInformationTrafficRulesSCM - Data about the lane to the right of the mainLane (in driving direction)
laneRightRight	struct LaneInformationTrafficRulesSCM - Data about the lane two lanes right of the mainLane (in driving direction)

The basis for the respective variables is the following general struct LaneInformationTrafficRules:

Variable	Meaning	Default value
trafficSigns	Vector of all traffic signs valid for this lane inside the visibility distance

In SCM this struct is extended by the following struct LaneInformationTrafficRulesSCM:

Variable	Meaning	Default value
laneMarkingsLeft	List of lane markings on the left side of lane
laneMarkingsRight	List of lane markings on the right side of lane

GeometryInformation

The struct GeometryInformationSCM contains infrastructure information of surrounding lanes that describe its geometric features.

The general structure is shown in the following table.

Variable	Meaning	Default value
visibilityDistance	Current maximum visibility distance as specified by the world	-999
NumberOfLanes	Number of lane at the current position	-1
distanceToEndOfNextExit	Distance from current position to the end of the next (current or coming) exit lane	-999
distanceToEndOfNextEntry	Distance from current position to the end of the next (current or coming) entry lane	-999
laneLeftLeft	struct LaneInformationGeometrySCM - Data about the lane two lanes left of the mainLane (in driving direction)
laneLeft	struct LaneInformationGeometrySCM - Data about the lane to the left of the mainLane (in driving direction)
laneEgo	struct LaneInformationGeometrySCM - Data about the lane where the middle of the front of the agent is (e.g. mainLane)
laneRight	struct LaneInformationGeometrySCM - Data about the lane to the right of the mainLane (in driving direction)
laneRightRight	struct LaneInformationGeometrySCM - Data about the lane two lanes right of the mainLane (in driving direction)

The basis for the last three variables is the following general struct LaneInformationGeometry:

Variable	Meaning	Default value
exist	Wether there is a lane on this position	false (not existing)
curvature	Curvature at current s position	-999 (not existing)
width	Width at current s position	-999 (not existing)
distanceToEndOfLane	Distance from current position to the end of the lane	-999 (end is farther away than the visibility distance)

In SCM this struct is extended by the following struct LaneInformationGeometrySCM:

Variable	Meaning	Default value
curvatureInPreviewDistance	Curvature at previewDistance	-999 (not existing)
curvaturesToNearPoint	Curvatures at six positions equidistant between rear axle and 2m in front of the vehicles leading edge	-999 (not existing)
curvaturesToFarPoint	Curvatures at two positions equidistant between NearPoint (2m) and 8m in front of the vehicles leading edge	-999 (not existing)

SurroundingObjects

The struct SurroundingObjectsSCM contains data about all the objects in the different AreasOfInterest.

The general structure is shown in the following table.

Variable	Meaning	Default value
objectFront	struct ObjectInformationSCM - Data about the object in the AreasOfInterest EGO_FRONT
objectFrontFar	struct ObjectInformationSCM - Data about the object in the AreasOfInterest EGO_FRONT_FAR
objectRear	struct ObjectInformationSCM - Data about the object in the AreasOfInterest EGO_REAR
objectFrontLeft	struct ObjectInformationSCM - Data about the object in the AreasOfInterest LEFT_FRONT
objectFrontFarLeft	struct ObjectInformationSCM - Data about the object in the AreasOfInterest LEFT_FRONT_FAR
objectRearLeft	struct ObjectInformationSCM - Data about the object in the AreasOfInterest LEFT_REAR
objectSideLeft	vector<struct ObjectInformationSCM> - Vector containing data about all objects in the AreasOfInterest LEFT_SIDE
objectFrontRight	struct ObjectInformationSCM - Data about the object in the AreasOfInterest RIGHT_FRONT
objectFrontFarRight	struct ObjectInformationSCM - Data about the object in the AreasOfInterest RIGHT_FRONT_FAR
objectRearRight	struct ObjectInformationSCM - Data about the object in the AreasOfInterest RIGHT_REAR
objectSideRight	vector<struct ObjectInformationSCM> - Vector containing data about all objects in the AreasOfInterest RIGHT_SIDE
objectFrontLeftLeft	struct ObjectInformationSCM - Data about the object in the AreasOfInterest LEFTLEFT_FRONT
objectRearLeftLeft	struct ObjectInformationSCM - Data about the object in the AreasOfInterest LEFTLEFT_REAR
objectSideLeftLeft	vector<struct ObjectInformationSCM> - Vector containing data about all objects in the AreasOfInterest LEFTLEFT_SIDE
objectFrontRightRight	struct ObjectInformationSCM - Data about the object in the AreasOfInterest RIGHTRIGHT_FRONT
objectRearRightRight	struct ObjectInformationSCM - Data about the object in the AreasOfInterest RIGHTRIGHT_REAR
objectSideRightRight	vector<struct ObjectInformationSCM> - Vector containing data about all objects in the AreasOfInterest RIGHTRIGHT_SIDE

The basis for the respective variables is the following general struct ObjectInformation, which is used to transport data of an object as seen by the driver:

Variable	Meaning	Default value
id	Id of the object	-1 (not existing)
exist	False if there is no object in this position	false
isStatic	True if stationary object, false if agent	false
velocity	Absolute velocity of the agent	-999 (object is not an agent)
acceleration	Acceleration of the agent	-999 (object is not an agent)
heading	Heading relative to the street	-999 (not existing)
length	Length of object	-999 (not existing)
width	Width of object	-999 (not existing)
height	Heigth of object	-999 (not existing)
relativeLongitudinalDistance	Relative distance along the road (i.e. in direction s) between own agent and object	-999 (not existing)
relativeLateralDistance	Relative distance at right angle to the road (i.e in direction t) between own agent and object	-999 (not existing)

In SCM this struct is extended by the following struct ObjectInformationSCM:

Variable	Meaning	Default value
distanceToLaneBoundaryLeft	Distance between the left front point and the left boundary of the lane it is in	-999
distanceToLaneBoundaryRight	Distance between the right front point and the right boundary of the lane it is in	-999
collision	Wether this object has collided with another object	false
isCrossingLanes	Wether the agent touches multiple neighbouring lanes	false
brakeLightsActive	Wether the brake lights of the agent are on (false if not an agent)	false
indicatorState	State of the indicator of the agent	off (not an agent)
mainLaneId	Id of the middle of the reference point of the agent	-999
obstructionScm	Obstruction information between object and own agent (i.e. information about relative lateral distances (left and right))
lateralPositionInLane	t-coordinate	-999
longitudinalVelocity	Velocity in direction of s	-999
lateralVelocity	Velocity in direction of t	-999

ObstructionScm

ObstructionScm expands on the already existing Obstruction information from the agent interface and adjusts the data in accordance with conventions used in SCM.

While Obstruction represents the lateral distance for the front center (i.e. center of the front of the bounding box) to pass the observed object on its right or left hand side ObstructionScm will also factor in the dimensions of the ego agent. The right and left component will contain the lateral displacement required for the ego agent to completely pass the observed object on its respective side. In addition, ObstructionScm will also comprise the lateral displacement of the ego vehicle due to a heading angle. As displayed in the graphic below the frontal displacement component is calculated by the product of the vehicle half width and the cosine of the heading angle. For the value of the rear displacement component the frontal value (or distance due to vehicle width) is added to the product of the vehicle length and the sine of the heading angle. In combination with the Obstruction, it results in the lateral displacements required to pass the observed object on either its left or right side.

Fig. 62 Ego geoometry and heading influence for ObstructionScm

The second major difference between Obstruction and ObstructionScm is in its sign convention. ObstructionScm will net a positive value on either side when there is a distance to overcome and a negative value when the ego agent is already on the desired side.

Longitudinal obstruction

Similar to the lateral obstruction above SensorDriverScm also determines a lateral obstruction. It contains the values

front: Longitudinal distance for the ego agent to be ahead of the observed object
rear: Longitudinal distance for the ego agent to be behind of the observed object
isOverlapping: Flag, indicating an overlapping of the two objects in longitudinal direction

The sign convention is in line with the lateral counterpart. Positive values indicate that a distance needs to be overcome, as depicted in the graphic blow.

Fig. 64 Longitudinal obstruction sign convention

To determine these values the position of the front and rear of the ego agent and the observed object is calculated. This can be achieved by combination of the distance to start of road and length of the respective objects. This information are enough to determine whether the observed object is entirely in front, entirely behind or next to (entirely or partially) the ego agent and allows for the LongitudinalObstruction values be set accordingly. The longitudinal obstruction does not factor in the heading of the ego agent in its current form.

Lateral position in lane

In order to determine the lateral position of an object in its lane the distance between the ego agent and the lane center the observed object resides in must be determined. This is done with the help of the relative lateral distance between the two objects, the lane widths of all lanes between them and the lateral position in lane of the ego agent. The object’s lateral position results from the difference between the relative lateral distance and the distance to its lane center.

Distance to lane boundary

First the distance from the ego agent to the lane boundaries of the observed object’s lane boundaries is determined. This can be done with the help of ego’s lateral position in lane, the all lane width between and including ego’s lane and the object’s lane. With respective difference between the resulting distance to object’s left and right boundary and the Obstruction values left and right the distances between the object and it’s left and right lane boundary can be calculated. A positive value indicates that the object has not crossed the respective lane marking, while a negative value is the distance that it has already exceeded.