• Emergency
Emergency

Emergency Vehicle Simulation#

The simulation of emergency vehicles and their special rights is possible with SUMO.

Vehicle Class 'emergency'#

If a vehicle is assigned a vType with vClass="emergency", the following features are activated:

  • the vehicle will receive the default shape and size for a rescue vehicle.
  • the vehicle may drive on lanes that allow "emergency" (but which might disallow normal passenger traffic).
  • the vehicle may overtake on the right in all traffic situations.
  • the vehicle may drive through the opposite direction edge even when its own edge has multiple usable lanes.
  • the vehicle may overtake through the opposite direction edge even when its leader vehicle also wants to change left.
  • the vehicle may overtake through the opposite direction edge even when it's approaching an intersection without priority.
  • the vehicle may overtake through the opposite direction edge even when it must overtake a long column of vehicles (up to 1000m).

Blue Light Device#

A Blue light device indicates that the emergency vehicle is driving with special rights (using a siren and blue flashing lights). See here for how to define this device for specific vehicle types or individual vehicles. The device activates the following features:

  • the vehicle will ignore red traffic lights.
  • once the vehicle is jammed (waitingTime > 1s) it will perform lane changing without regard to strategic considerations (it will use any lane that allows it to advance along the road).
  • if the vehicle is at an intersection but in the wrong turning lane, it will enter the intersection anyway (performing a silent teleport to the closest internal lane that allows it to continue its route).

If the simulation is running with the sublane model (--lateral-resolution is set to a value > 0), other traffic participants are forced to form a virtual middle lane (rescue lane) to let the emergency vehicle pass. The following behaviors are activated for surrounding traffic ahead of the device-equipped vehicle:

  • vehicles on the leftmost lane move towards the left side (latAlignment="left").
  • vehicles on all other lanes move towards the right side (latAlignment="right").
  • vehicles do not perform any lane changes (in particular, they do not move into the rescue lane).
  • after the emergency vehicle has passed, the vehicles resume normal driving (with their previous lateral alignment).

Vehicles that are forming a rescue lane will have generic parameter key rescueLane set to a space-separated list of emergency vehicle ids that are influencing them.

Surrounding traffic reacts while within 25m of the device-equipped vehicle. This distance is configurable by:

Further Features for driving with special rights#

  • Disregarding right-of-way and traffic lights:
  • Exceeding the speed limit: This is supported by setting the vType-attribute speedFactor (a value of 1.5 allows driving with 150% of the road speed limit).

Example Configuration#

<vType id="rescue" vClass="emergency" speedFactor="1.5">
   <param key="has.bluelight.device" value="true"/>
</vType>

Further Parameters#

The following generic parameters can be used to configure a bluelight device:

  • "device.bluelight.reactiondist": overrides option --device.bluelight.reactionDist

The following generic parameters can be used to configure surrounding traffic w.r.t their reaction to a bluelight device:

  • "device.bluelight.reaction-prob-near": probably for a vehicle to react (per second) and start forming a rescue lane while near (default 0.577)
  • "device.bluelight.reaction-prob-far": probably for a vehicle to react (per second) and start forming a rescue lane while far away (default 0.189)
  • "device.bluelight.near-dist": distance threshold to distinguish between near and far (for the above probabilities)

Visualization#

The visualization of emergency vehicles is supported in sumo-gui. When setting the vType-attribute guiShape="emergency", a white vehicle with the international sign for first aid is drawn. Alternatively, a police car or a fire brigade will be drawn when setting the vType-attribute guiShape="police" or guiShape="firebrigade", respectively. Furthermore, a blue flashing light will be visible on the vehicle when setting the vType-attribute vClass="emergency".

Ev.png

References#

Bieker, Laura (2015) Traffic safety evaluations for Emergency Vehicles. Young Researchers Seminar, 17.-19. June 2015, Rome, Italy.

Bieker, Laura (2011) Emergency Vehicle Prioritization using Vehicle-To-Vehicle Communication. Young Researchers Seminar, 8.-10. June 2011, Copenhagen, Denmark.