Package org.opentrafficsim.road.gtu.lane.perception.headway

Class HeadwayGtuReal

java.lang.Object
org.opentrafficsim.road.gtu.lane.perception.headway.AbstractHeadway
org.opentrafficsim.road.gtu.lane.perception.headway.HeadwayGtuReal
All Implemented Interfaces:
Serializable, Comparable<Headway>, org.djutils.base.Identifiable, PerceivedObject, Headway, HeadwayGtu
public class HeadwayGtuReal extends AbstractHeadway implements HeadwayGtu
Container for a reference to information about a (lane based) GTU and a headway. The Headway can store information about GTUs or objects ahead of the reference GTU, behind the reference GTU, or (partially) parallel to the reference GTU. In addition to the (perceived) headway, several other pieces of information can be stored, such as (perceived) speed, (perceived) acceleration, (perceived) turn indicators, and (perceived) braking lights.
This particular version returns behavioral information about the observed GTU objects based on their real state.
Special care must be taken in curves when perceiving headway of a GTU or object on an adjacent lane.The question is whether we perceive the parallel or ahead/behind based on a line perpendicular to the front/back of the GTU (rectangular), or perpendicular to the center line of the lane (wedge-shaped in case of a curve). The difficulty of a wedge-shaped situation is that reciprocity might be violated: in case of a clothoid, for instance, it is not sure that the point on the center line when projected from lane 1 to lane 2 is the same as the projection from lane 2 to lane 1. The same holds for shapes with sharp bends. Therefore, algorithms implementing headway should only project the reference point of the reference GTU on the center line of the adjacent lane, and then calculate the forward position and backward position on the adjacent lane based on the reference point. Still, our human perception of what is parallel and what not, is not reflected by fractional positions.

Copyright (c) 2013-2024 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved.
BSD-style license. See OpenTrafficSim License.

Author:
Alexander Verbraeck, Peter Knoppers, Wouter Schakel
See Also:

  • Constructor Details

    • HeadwayGtuReal

      public HeadwayGtuReal(LaneBasedGtu gtu, org.djunits.value.vdouble.scalar.Length distance, boolean facingSameDirection) throws GtuException
      Construct a new Headway information object, for a GTU ahead of us or behind us.
      Parameters:
      gtu - LaneBasedGtu; the observed GTU, can not be null.
      distance - the distance to the other object; if this constructor is used, distance cannot be null.
      facingSameDirection - boolean; whether the GTU is facing the same direction.
      Throws:
      GtuException - when id is null, objectType is null, or parameters are inconsistent

    • HeadwayGtuReal

      public HeadwayGtuReal(LaneBasedGtu gtu, org.djunits.value.vdouble.scalar.Length overlapFront, org.djunits.value.vdouble.scalar.Length overlap, org.djunits.value.vdouble.scalar.Length overlapRear, boolean facingSameDirection) throws GtuException
      Construct a new Headway information object, for a GTU parallel with us.
      Parameters:
      gtu - LaneBasedGtu; the observed GTU, can not be null.
      overlapFront - the front-front distance to the other Gtu; if this constructor is used, this value cannot be null.
      overlap - the 'center' overlap with the other Gtu; if this constructor is used, this value cannot be null.
      overlapRear - the rear-rear distance to the other Gtu; if this constructor is used, this value cannot be null.
      facingSameDirection - boolean; whether the GTU is facing the same direction.
      Throws:
      GtuException - when id is null, or parameters are inconsistent

  • Method Details

    • getCarFollowingModel

      public final CarFollowingModel getCarFollowingModel()
      Many models that observe a GTU need to predict the imminent behavior of that GTU. Having a car following model of the observed GTU can help with that. The car following model that is returned can be on a continuum between the actual car following model of the observed GTU and the own car following model of the observing GTU, not making any assumptions about the observed GTU. When successive observations of the GTU take place, parameters about its behavior can be estimated more accurately. Another interesting easy-to-implement solution is to return a car following model per GTU type, where the following model of a truck can differ from that of a car.
      Specified by:
      getCarFollowingModel in interface HeadwayGtu
      Returns:
      a car following model that represents the expected behavior of the observed GTU

    • getParameters

      public final org.opentrafficsim.base.parameters.Parameters getParameters()
      Many models that observe a GTU need to predict the imminent behavior of that GTU. Having an estimate of the behavioral characteristics of the observed GTU can help with that. The parameters that are returned can be on a continuum between the actual parameters of the observed GTU and the own parameters of the observing GTU, not making any assumptions about the observed GTU. When successive observations of the GTU take place, parameters about its behavior can be estimated more accurately. Another interesting easy-to-implement solution is to return a set of parameters per GTU type, where the parameters of a truck can differ from that of a car.
      Specified by:
      getParameters in interface HeadwayGtu
      Returns:
      the parameters that represent the expected behavior of the observed GTU

    • getSpeedLimitInfo

      public final SpeedLimitInfo getSpeedLimitInfo()
      Many models that observe a GTU need to predict the imminent behavior of that GTU. Having a model of the speed info profile for the observed GTU can help with predicting its future behavior. The speed limit info that is returned can be on a continuum between the actual speed limit model of the observed GTU and the own speed limit model of the observing GTU, not making any assumptions about the observed GTU. When successive observations of the GTU take place, parameters about its behavior, such as the maximum speed it accepts, can be estimated more accurately. Another interesting easy-to-implement solution is to return a speed limit info object per GTU type, where the returned information of a truck -- with a maximum allowed speed on 80 km/h -- can differ from that of a car -- which can have a maximum allowed speed of 100 km/h on the same road.
      Specified by:
      getSpeedLimitInfo in interface HeadwayGtu
      Returns:
      a speed limit model that helps in determining the expected behavior of the observed GTU

    • getRoute

      public final Route getRoute()
      Models responding to other GTU may assume a route of the vehicle, for instance at intersections. The route may be short, i.e. only over the next intersection. Implementations may return anything from the actual route, a route based on indicators and other assumptions, or null if simply not known/estimated.
      Specified by:
      getRoute in interface HeadwayGtu
      Returns:
      route of gtu

    • moved

      public final HeadwayGtu moved(org.djunits.value.vdouble.scalar.Length headway, org.djunits.value.vdouble.scalar.Speed speed, org.djunits.value.vdouble.scalar.Acceleration acceleration)
      Creates a copy with different headway, speed and possibly acceleration. It may not be alongside. This method is used to anticipate movement of a neighboring GTU.

      Note: when moving a HeadwayGtuRealDirect, only headway, speed and acceleration may be considered to be delayed and anticipated. Other information is taken from the actual GTU at the time moved() is called.
      Specified by:
      moved in interface HeadwayGtu
      Parameters:
      headway - Length; headway
      speed - Speed; speed
      acceleration - Acceleration; acceleration
      Returns:
      copy with different headway, speed and possibly acceleration

    • getId

      public final String getId()
      Specified by:
      getId in interface Headway
      Specified by:
      getId in interface org.djutils.base.Identifiable
      Returns:
      String; the id of the other object for comparison purposes, cannot be null.

    • getLength

      public final org.djunits.value.vdouble.scalar.Length getLength()
      Specified by:
      getLength in interface Headway
      Returns:
      Length; the length of the other object; can be null if unknown.

    • getWidth

      public org.djunits.value.vdouble.scalar.Length getWidth()
      Returns the width of the GTU.
      Specified by:
      getWidth in interface HeadwayGtu
      Returns:
      Length; width of the GTU

    • getSpeed

      public final org.djunits.value.vdouble.scalar.Speed getSpeed()
      Specified by:
      getSpeed in interface Headway
      Returns:
      Speed; the (perceived) speed of the other object; can be null if unknown.

    • getDesiredSpeed

      public org.djunits.value.vdouble.scalar.Speed getDesiredSpeed()
      Returns the perceived desired speed of the neighbor.
      Specified by:
      getDesiredSpeed in interface HeadwayGtu
      Returns:
      Speed; perceived desired speed of the neighbor

    • getObjectType

      public final Headway.ObjectType getObjectType()
      Specified by:
      getObjectType in interface Headway
      Returns:
      Length; the (perceived) object Type, can be null if no object type unknown.

    • getAcceleration

      public final org.djunits.value.vdouble.scalar.Acceleration getAcceleration()
      Specified by:
      getAcceleration in interface Headway
      Returns:
      Acceleration; acceleration the (perceived) acceleration of the other object; can be null if unknown.

    • getGtuType

      public final GtuType getGtuType()
      Specified by:
      getGtuType in interface HeadwayGtu
      Returns:
      gtuType

    • isFacingSameDirection

      public final boolean isFacingSameDirection()
      Specified by:
      isFacingSameDirection in interface HeadwayGtu
      Returns:
      facingSameDirection

    • isBrakingLightsOn

      public final boolean isBrakingLightsOn()
      Specified by:
      isBrakingLightsOn in interface HeadwayGtu
      Returns:
      were the braking lights on?

    • isLeftTurnIndicatorOn

      public final boolean isLeftTurnIndicatorOn()
      Specified by:
      isLeftTurnIndicatorOn in interface HeadwayGtu
      Returns:
      was the left turn indicator on?

    • isRightTurnIndicatorOn

      public final boolean isRightTurnIndicatorOn()
      Specified by:
      isRightTurnIndicatorOn in interface HeadwayGtu
      Returns:
      was the right turn indicator on?

    • isEmergencyLightsOn

      public final boolean isEmergencyLightsOn()
      Specified by:
      isEmergencyLightsOn in interface HeadwayGtu
      Returns:
      were the emergency lights on?

    • isHonking

      public final boolean isHonking()
      Specified by:
      isHonking in interface HeadwayGtu
      Returns:
      was the vehicle honking or ringing its bell when being observed for the headway?

    • toString

      public final String toString()
      Overrides:
      toString in class AbstractHeadway