How to ensure that environment events are on the road network?

[phil-hei]

Hi,

I just wonder if there is an (easy) way to make sure that environment events, such as an obstacle, are placed on the road network so that vehicle can pass them by. Example: I have a defined simulation area where I want to generate random obstacles on the road. I'm able to generate this events within the simulation area, but haven't found a suitable way to ensure that they are on the road network.

[schwepmo]

Hey @phil-hei, could you extend a little bit on your question, also example configuration always help.
I assume you're using SUMO as a traffic simulator and the Environment Simulator to place your "obstacles". If that's the case then what you're trying to achieve might not be as straight forward as you're planning.
The Environment Simulator doesn't directly couple to SUMO, i.e., environment events do not get passed to the traffic simulation and thereby the road network directly. Instead, the applications running on your vehicles may react on the events (see the Weather Warning Apps).

Alternatively, there is the option to "close" lanes using TMC's changeLaneState functionality (see here). However, vehicles may behave weirdly if they are on a lane while it is being closed.

Lastly, if you just want a static obstacle throughout the simulation, there is the option of placing a halting vehicle (see for example here), which will be evaded by other vehicles automatically.

I hope these ideas help you to solve your issue, please feel free to elaborate!

[phil-hei]

Thanks for your extensive answer!
Indeed, I want to use SUMO and extend the traffic simulation with environmental events, such as obstacles on the way. Vehicles should recognize these obstacles during driving and share this information with the cloud so that other vehicles can be warned. Therefore, I just thought about how to ensure that static obstacles are placed onto the road network.
I didn't consider that these simulators are not coupled, but probably I will try out to equip vehicles with an application similar to the Weather Warning App. In this way, I can achieve what I want.
Now I just have to find a way to place static obstacles on the road network and not besides.

[kschrab]

I found a thread in the SUMO mailing list which suggests to just add a vehicle and stop it immediately at their spawn position to mimic an obstacle that other vehicles can react to and overtake it. You can either do that the "right" way, by adding a specific application which stops a vehicle as soon as it spawns, or by "hacking" the SumoAmbassador.

By spawning a vehicle and using a custom application which stops the vehicle (might not be accurate enough):

public void onVehicleUpdated(VehicleData previous, VehicleData updated) {
  if (previous == null)  {
    getOs().stopNow(VehicleStopMode.STOP, Long.MAX_VALUE);
  }
}

or by spawning a specific vehicle of type "Obstacle" and then adjusting the SumoAmbassador in line 302:

- bridge.getSimulationControl().addVehicle(vehicleId, routeId, vehicleType, laneId, departPos, departSpeed);
+ if (vehicleType.equals("Obstacle")) {
+    bridge.getSimulationControl().addVehicle(vehicleId, routeId, vehicleType, laneId, departPos, "0");
+    bridge.getVehicleControl().stop(vehicleId, routes.get(routeId).getConnectionIds().iterator().next(), vehicleRegistration.getDeparture().getDeparturePos(), vehicleRegistration.getDeparture().getDepartureLane(), Long.MAX_VALUE, VehicleStopMode.STOP);
+} else {
+    bridge.getSimulationControl().addVehicle(vehicleId, routeId, vehicleType, laneId, departPos, departSpeed);
+}