avoid orthogonal sliding in sublane model (trac #3392) - Githubissues

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Eclipse SUMO is an open source, highly portable, microscopic and continuous traffic simulation package designed to handle large networks. It allows for intermodal simulation including pedestrians and comes with a large set of tools for scenario creation.

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avoid orthogonal sliding in sublane model (trac #3392) #3392

Open behrisch opened 6 years ago

behrisch commented 6 years ago

to prevent deadlocks it cannot be totally prevented but at least it should be avoided where possible

Migrated from http://sumo.dlr.de/ticket/3392

{
    "status": "new", 
    "changetime": "2017-09-06T08:01:50Z", 
    "description": "to prevent deadlocks it cannot be totally prevented but at least it should be avoided where possible\n", 
    "reporter": "namdre", 
    "cc": "", 
    "resolution": "", 
    "_ts": "1504684910223519", 
    "component": "sharps", 
    "summary": "avoid orthogonal sliding in sublane model", 
    "priority": "major", 
    "keywords": "", 
    "time": "2017-09-06T08:01:50Z", 
    "milestone": "1.0.0", 
    "owner": "", 
    "type": "defect"
}

related to #4017

namdre commented 6 years ago

add lcmodel parameters for setting an upper bound on lateral speed depending on longitudinal speed.

lcMaxSpeedLatStanding lcMaxSpeedLatFactor

where lateralSpeed <= MIN(lcMaxSpeedLatStanding + lcMaxSpeedLatFactor * getSpeed(), vtype.getMaxSpeedLat())

leoluecken commented 6 years ago

You might also consider sth like: maxAccelLat -> maxAccelLatStanding + lcMaxAccelLatFactor * getSpeed()

namdre commented 5 years ago

sliding should be totally disabled for non-urgent changes (except for bicycles)

namdre commented 2 years ago

solution: in addition to maxSpeedLatStanding, maxSpeedLatFactor add two new parameters ~~maxSpeedLatStandingStrategic, maxSpeedLatFactorStrategic~~ maxSpeedLatStandingUrgent, maxSpeedLatFactorUrgent to explicitly configure the two different situations. (i.e. the urgent version with negative factor #8064)

using Urgent as the suffix is better than Strategic because other lane change motivations may be flagged as urgent in the future (#1145) and it makes sense to apply the new value there as well.

namdre commented 2 years ago

lcMaxSpeedLatStanding=0 results in unrealistic behavior where vehicles begin a lane changing maneuver (i.e. to gain speed) and are then stuck in mid-maneuver once their forward space runs out and they have to stop.

Fixing this has several aspects:

maneuvers are started to late (which might be remedied with lcSpeedGainLookahead)
before a maneuver is begun, the remaining forward space needed for completion must be checked
it looks very unrealistic if vehicles need only a small lateral movement to achieve their desired maneuver (which they could accomplish in real life with a small violation of minGap) but are stuck in the simulation due to lcMaxSpeedLatStanding=0. Maybe maneuverDist must be taken into account as well.
vehicles should never get stuck across lane boundaries since drivers in real life would also be careful avoid this situation. In this case "sliding" would be the better way out.

namdre commented 2 years ago

Idea: prevent non-urgent maneuvers if maneuverDist is greater than some threshold + brakeDist. Threshold could be something like half a lane width.

vehicles could always return from between lane bounds
small maneuvers (that look plausible) would still be permitted
wide-slidey maneuvers for speedGain/keepRight would cease.

Problem: lane changes may still be started and not finished if the lateral speed is not high enough to pass the threshold until the vehicle has to stop.

namdre commented 2 years ago

Next Idea: use a function of myMaxDistLatStanding, brakeGap and maneuverDist to affect changes in mySpeedGainProbability and myKeepRightProbability

namdre commented 2 years ago

to be done:

apply maxDistLatStanding to keepRight execution (currently only affects motivation growth which permits delayed changing after a blocking vehicle has passed)
apply maxDistLatStanding to speedGain changes (motivation growth / execution) - depends on #10487