Package org.opentrafficsim.road.gtu.tactical.util

Class TrafficLightUtil

java.lang.Object

org.opentrafficsim.road.gtu.tactical.util.TrafficLightUtil

public final class TrafficLightUtil
extends Object

Static methods regarding traffic lights for composition in tactical planners.

Copyright (c) 2013-2026 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved.
BSD-style license. See OpenTrafficSim License.

Author:

Wouter Schakel

Field Summary

Fields

Modifier and Type	Field	Description
static final ParameterTypeAcceleration	BCRIT	Maximum deceleration for stopping for yellow traffic light.
static final ParameterTypeLength	S0	Car-following stopping distance.

Method Summary

Modifier and Type	Method	Description
static org.djunits.value.vdouble.scalar.Acceleration	respondToTrafficLight(TacticalContextEgo context, PerceivedTrafficLight headwayTrafficLight)	Returns an acceleration as response to a traffic light, being positive infinity if ignored.
static org.djunits.value.vdouble.scalar.Acceleration	respondToTrafficLights(TacticalContextEgo context, RelativeLane lane, org.djunits.value.vdouble.scalar.Length mergeDistance, boolean onRoute)	Returns an acceleration as response to a set of traffic lights, being positive infinity if ignored.

Methods inherited from class java.lang.Object

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

Field Details

BCRIT

public static final ParameterTypeAcceleration BCRIT

Maximum deceleration for stopping for yellow traffic light.

S0

public static final ParameterTypeLength S0

Car-following stopping distance.

Method Details

respondToTrafficLights

public static org.djunits.value.vdouble.scalar.Acceleration respondToTrafficLights(TacticalContextEgo context,
 RelativeLane lane,
 org.djunits.value.vdouble.scalar.Length mergeDistance,
 boolean onRoute)
                                                                            throws ParameterException,
OperationalPlanException

Returns an acceleration as response to a set of traffic lights, being positive infinity if ignored. The response is governed by the car-following model in case a traffic light is yellow or red. A constant deceleration to stop is also calculated, and the highest acceleration of both is used. If this value is below -bYellow (B_YELLOW), the traffic light is ignored, which usually occurs only during the yellow phase. By using the highest acceleration of the car-following model and the constant deceleration, it is ensured that comfortable deceleration is applied if approaching a red traffic light from far away, while strong deceleration is only applied if required and appropriately represents stopping for yellow.

Parameters:

context - tactical information such as parameters and car-following model

lane - lane

mergeDistance - distance along which no lane changes can be performed towards the lane

onRoute - filter conflicts to only include conflict on the route

Returns:

acceleration as response to a traffic light, being positive infinity if ignored

Throws:

ParameterException - if a parameter is not defined

OperationalPlanException - if intersection perception category does not exist

NullPointerException - if any input is null

IllegalArgumentException - if the traffic light is not downstream

respondToTrafficLight

public static org.djunits.value.vdouble.scalar.Acceleration respondToTrafficLight(TacticalContextEgo context,
 PerceivedTrafficLight headwayTrafficLight)
                                                                           throws ParameterException

Returns an acceleration as response to a traffic light, being positive infinity if ignored. The response is governed by the car-following model in case the traffic light is yellow or red. A constant deceleration to stop is also calculated, and the highest acceleration of both is used. If this value is below -bYellow (B_YELLOW), the traffic light is ignored, which usually occurs only during the yellow phase. By using the highest acceleration of the car-following model and the constant deceleration, it is ensured that comfortable deceleration is applied if approaching a red traffic light from far away, while strong deceleration is only applied if required and appropriately represents stopping for yellow.

Parameters:

context - tactical information such as parameters and car-following model

headwayTrafficLight - headway traffic light

Returns:

acceleration as response to a traffic light, being positive infinity if ignored

Throws:

ParameterException - if a parameter is not defined

NullPointerException - if any input is null

IllegalArgumentException - if the traffic light is not downstream