Introduction#
Since version 1.9.1 SUMO supports simulation of Green Light Optimal Speed Advisory (GLOSA) via the glosa device. This allows vehicles to avoid stops at traffic lights when the phase is about to change.
Note
While the glosa capabilities are under development, their status can be checked via Issue #7721.
Equipping vehicles#
To attach a glosa device to a vehicle, the standard device-equipment
procedures can
be applied using <device name>=glosa
.
For instance, a single vehicle can be equipped with glosa as in the following minimal example
<vehicle id="v0" route="route0" depart="0">
<param key="has.glosa.device" value="true"/>
</vehicle>
GLOSA functions#
Slowing Down#
When a vehicle is approaching a red light the time until reaching the stop line is compared with the time until the signal (for the intended movement) changes to green. If the vehicle would reach the stop line before the switch, a slow-down maneuver may be undertaken.
If the speed can be reduced within reasonable bounds (glosa.min-speed), the speed is reduced to the maximum possible value so that the vehicle reaches the stop line at the time of the phase change.
Speeding up#
When a vehicle is approaching a green light and the time until reaching the stop line is higher than the remaining green phase duration, a speed-up maneuver may be undertaken.
If driving with a higher speedFactor (configured with glosa.max-speedfactor) allows to reach the stop line within the remaining green time, the speedFactor is set to a higher value.
The speedFactor is changed back to the default after passing the traffic light.
Traffic lights#
All traffic lights types supply time-to-switch information via the duration attribute of their phases.
Caution
This may cause invalid maneuvers with traffic-actuated traffic lights that may vary their phase duration.
The communication range may be customized by setting param "device.glosa.range" on the tlLogic. This may also be used to disable glosa functions for specific intersections. To update the parameter for a program that is embedded in the .net.xml file the following element can be loaded via --additional-files:
<tlLogic id="C" programID="0">
<param key="device.glosa.range" value="60"/>
</tlLogic>
Parameters#
The following parameters affect the operation of the glosa device.
- device.glosa.range: (maximum range from stop line at which glosa functions become active (default 100). If the current traffic light also sets this parameter, the minimum value of the device and tls parameter is used.
- device.glosa.min-speed: minimum speed for slow-down maneuver (default 5m/s)
- device.glosa.max-speedfactor: maximum speedFactor for trying to reach a green light (default 1.1) Setting a value of 1 will ensure perfect compliance with the speed limit but may still cause slow drivers to speed up.
- jmDriveAfterYellowTime: This junction model parameter encodes willingness to continue driving at yellow depending on running duration of the yellow phase (default 0). The value will be taken into account when checking the feasibility of a speed-up maneuver
All device parameters may be set via
- sumo option: --device.glosa.range 150
- vType parameter:
<param key="device.glosa.min-speed" value="6"/>
- vehicle parameter:
<param key="device.max.speedfactor" value="1.2"/>