org.opentrafficsim.road.gtu.following

Class AbstractGTUFollowingModel

java.lang.Object

org.opentrafficsim.road.gtu.following.AbstractGTUFollowingModel

All Implemented Interfaces:

GTUFollowingModel

Direct Known Subclasses:

FixedAccelerationModel, IDM, IDMPlus, SequentialFixedAccelerationModel

public abstract class AbstractGTUFollowingModel
extends Object
implements GTUFollowingModel

Code shared between various car following models.

Copyright (c) 2013-2015 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved.
BSD-style license. See OpenTrafficSim License.

Version:

$Revision: 1408 $, $LastChangedDate: 2015-09-24 15:17:25 +0200 (Thu, 24 Sep 2015) $, by $Author: pknoppers $, initial version 19 feb. 2015

Author:

Alexander Verbraeck, Hans van Lint, Peter Knoppers, Guus Tamminga, Yufei Yuan

Field Summary

Fields

Modifier and Type	Field and Description
static DualAccelerationStep	TOODANGEROUS Return value if lane change causes immediate collision.

Constructor Summary

Constructors

Constructor and Description
AbstractGTUFollowingModel()

Method Summary

Modifier and Type	Method and Description
DualAccelerationStep	computeAcceleration(LaneBasedGTU referenceGTU, Collection<HeadwayGTU> otherGTUs, org.djunits.value.vdouble.scalar.Speed speedLimit) Compute the lowest accelerations (or most severe decelerations) that would be used if a referenceGTU is present (inserted, or not removed) in a set of other GTUs. If any GTU in the set of otherGTUs has a null headway (indicating that the other GTU is in fact parallel to the referenceGTU), prohibitive decelerations shall be returned. Two AccelerationStep values are returned in a DualAccelerationStep. TODO We should probably add a be ready to stop before argument to prevent vehicles that cannot see their leader, or should slow down for a crossing from accelerating to unsafe speeds.
AccelerationStep	computeAcceleration(LaneBasedGTU follower, org.djunits.value.vdouble.scalar.Speed leaderSpeed, org.djunits.value.vdouble.scalar.Length.Rel headway, org.djunits.value.vdouble.scalar.Speed speedLimit) Compute the acceleration that would be used to follow a leader. TODO We should probably add a be ready to stop before argument to prevent vehicles that cannot see their leader, or should slow down for a crossing from accelerating to unsafe speeds.
AccelerationStep	computeAccelerationWithNoLeader(LaneBasedGTU gtu, org.djunits.value.vdouble.scalar.Speed speedLimit) Compute the acceleration that would be used if the is not leader in sight.
org.djunits.value.vdouble.scalar.Length.Rel	minimumHeadway(org.djunits.value.vdouble.scalar.Speed followerSpeed, org.djunits.value.vdouble.scalar.Speed leaderSpeed, org.djunits.value.vdouble.scalar.Length.Rel precision, org.djunits.value.vdouble.scalar.Speed speedLimit, org.djunits.value.vdouble.scalar.Speed followerMaximumSpeed) Compute the minimum net headway given the speed of the follower and the leader. At the returned headway, the follower would decelerate with it's maximum comfortable deceleration.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.opentrafficsim.road.gtu.following.GTUFollowingModel

computeAcceleration, getLongName, getName, getStepSize, maximumSafeDeceleration

Field Detail

TOODANGEROUS

public static final DualAccelerationStep TOODANGEROUS

Return value if lane change causes immediate collision.

Constructor Detail

AbstractGTUFollowingModel

public AbstractGTUFollowingModel()

Method Detail

computeAcceleration

public final DualAccelerationStep computeAcceleration(LaneBasedGTU referenceGTU,
                                                      Collection<HeadwayGTU> otherGTUs,
                                                      org.djunits.value.vdouble.scalar.Speed speedLimit)
                                               throws org.opentrafficsim.core.network.NetworkException

Compute the lowest accelerations (or most severe decelerations) that would be used if a referenceGTU is present (inserted, or not removed) in a set of other GTUs.
If any GTU in the set of otherGTUs has a null headway (indicating that the other GTU is in fact parallel to the referenceGTU), prohibitive decelerations shall be returned.
Two AccelerationStep values are returned in a DualAccelerationStep.
TODO We should probably add a be ready to stop before argument to prevent vehicles that cannot see their leader, or should slow down for a crossing from accelerating to unsafe speeds.

Specified by:

computeAcceleration in interface GTUFollowingModel

Parameters:

referenceGTU - LaneBasedGTU; the GTU for which the accelerations are computed

otherGTUs - Collection<HeadwayGTU>; the other GTUs. A negative headway value indicates that the other GTU is a follower. NB. If the referenceGTU is contained in this Collection, it is ignored.

speedLimit - DoubleScalar.Abs<SpeedUnit>; the local speed limit

Returns:

DualAccelerationStep; the result with the lowest accelerations (or most severe decelerations) of application of the GTU following model of the referenceGTU for each leader and follower

Throws:

org.opentrafficsim.core.network.NetworkException - on network inconsistency

computeAcceleration

public final AccelerationStep computeAcceleration(LaneBasedGTU follower,
                                                  org.djunits.value.vdouble.scalar.Speed leaderSpeed,
                                                  org.djunits.value.vdouble.scalar.Length.Rel headway,
                                                  org.djunits.value.vdouble.scalar.Speed speedLimit)

Compute the acceleration that would be used to follow a leader.
TODO We should probably add a be ready to stop before argument to prevent vehicles that cannot see their leader, or should slow down for a crossing from accelerating to unsafe speeds.

Specified by:

computeAcceleration in interface GTUFollowingModel

Parameters:

follower - LaneBasedGTU; the GTU for which acceleration is computed

leaderSpeed - DoubleScalar.Abs<SpeedUnit>; the speed of the leader

headway - DoubleScalar.Rel<LengthUnit>; the headway of the leader

speedLimit - DoubleScalarAbs<SpeedUnit>; the local speed limit

Returns:

AccelerationStep; the result of application of the GTU following model

computeAccelerationWithNoLeader

public final AccelerationStep computeAccelerationWithNoLeader(LaneBasedGTU gtu,
                                                              org.djunits.value.vdouble.scalar.Speed speedLimit)
                                                       throws org.opentrafficsim.core.network.NetworkException

Compute the acceleration that would be used if the is not leader in sight.

Specified by:

computeAccelerationWithNoLeader in interface GTUFollowingModel

Parameters:

gtu - LaneBasedGTU; the GTU for which acceleration is computed

speedLimit - DoubleScalar.Abs<SpeedUnit>; the local speed limit

Returns:

AccelerationStep; the result of application of the GTU following model

Throws:

org.opentrafficsim.core.network.NetworkException - on network inconsistency

minimumHeadway

public final org.djunits.value.vdouble.scalar.Length.Rel minimumHeadway(org.djunits.value.vdouble.scalar.Speed followerSpeed,
                                                                        org.djunits.value.vdouble.scalar.Speed leaderSpeed,
                                                                        org.djunits.value.vdouble.scalar.Length.Rel precision,
                                                                        org.djunits.value.vdouble.scalar.Speed speedLimit,
                                                                        org.djunits.value.vdouble.scalar.Speed followerMaximumSpeed)

Compute the minimum net headway given the speed of the follower and the leader.
At the returned headway, the follower would decelerate with it's maximum comfortable deceleration.

Specified by:

minimumHeadway in interface GTUFollowingModel

Parameters:

followerSpeed - DoubleScalar.Abs<SpeedUnit>; speed of the follower

leaderSpeed - DoubleScalar.Abs<SpeedUnit>; speed of the leader

precision - DoubleScalar.Rel<LengthUnit>; the required precision of the result (must be > 0)

speedLimit - DoubleScalar.Abs<SpeedUnit>; the local speed limit

followerMaximumSpeed - DoubleScalar.Abs<SpeedUnit>; the maximum speed that the follower can drive at

Returns:

DoubleScalar.Rel<LengthUnit>