Add "road condition"

[hschoen]

Did I miss it or don't we have a parameter for the road condition?

• wet
• icy
• covered with snow
• oil
• sand
• leaves
• etc.

Also the layer thickness would be relevant (especially water layer for radar).
Coverage (in percent) of road?

[TimoHankeBMW]

No such parameter exists yet as there is no exactly specified and agreed-upon list of road conditions.
Especially the 'exactly specified' part makes this quite hard, e.g. 'wet' is a very broad und unspecific term, of whichi every usage instance will likely have a different understanding.
As discussions for specifications would likely fill many days' worth of workshops, I'd suggest that the best way is to wait for a specification from the scenario definition and use that. If these don't match, we would need to adapt anyway.

[PhilippRoethigBMW]

@hschoen and @TimoHankeBMW what do you think about implementing the condition of the road in a separate message? This message could define specific and measurable properties of the road rather than just determine a general category for it. Of course we would need to decide which properties would make sense.

//
// \brief The condition of the roads surface.
//
message RoadCondition
{
    // The temperature of the roads surface in degree Celsius.
    //
    optional double surface_temperature = 1;

    // The height of the water film on top of the surface in mm.
    //
    optional double surface_water_film = 2;

    // The temperature where the water on top of the surface would start to freeze or dew in degree Celsius.
    //
    optional double surface_freezing_point = 3;

    // The percentage of ice covering the road.
    //
    optional double surface_ice = 4;

    // The coefficient presenting the friction and the grip of the road.
    //
    optional double surface_friction = 5;
}

[hschoen]

@PhilippRoethigBMW, I think this is a good start! We should however merge this solution with the specification from the scenario definition as proposed by @TimoHankeBMW.
From a radar point of view I would like to add roughness of the road surface (clutter). Here we should use the definition used in environment simulation. @AndreasVIRES and @MHerrmannIPG , do you have a definition for roughness of the road surface?

[MHerrmannIPG]

@hschoen, no, there's currently no parameter for the roughness of the road surface. It's no problem to add a value to the test specification globally for the complete road network which then is available to any sensors. Making it variable along the track/in various areas of the network would be a bigger task.

[AndreasVIRES]

roughness
In OpenDRIVE there is a roughness value (without unit) in the Lane Material Record, I'll try to find out how this value typically is used (maybe mainly for sound simulation). Additionally OpenCRG can provide a very detailed "rough" surface.

road conditions
I would not recommend waiting for scenario definition. OpenSCENARIO is available in version 0.9 and we almost totally got rid of a road condition description and switched to a user specific effect/intensity list which for sure can contain something like "height of the water film on top of the surface" as an effect and the value in [mm] as intensity.
OpenDRIVE also allows setting an application specific surface material code and a friction value for lanes.

@hschoen I think there are two different things at least:

1. e.g. a surface roughness which influences the clutter for a radar and therefore the performance

2. Question: Are there sensors indicating specific surface conditions - like the detection of snow and ice?

For 1) we would just need values for the OSI:GT but for 2) we must clarify a definition of the sensor output in OSI:SD as well?

What do you think?