Hello, 1) Using the default car-following model, vehicles tend to drive as fast as possible and then brake as hard as possible (using 'decel'). This means they will brake with 'decel' at the latest possible moment when approaching the jam. Thus 'decel' functions more like a desired deceleration. Unfortunately, there is yet not concept for discriminating between desired and maximum deceleration.
2) Tau is the desired time gap to the follower which may be interpreted as a consequence of a drivers reaction time. However, reaction time is fundamentally limited by simulation step size. This why you will get a warning when using tau < step-size (it may lead to collisions). Also, when setting tau > step-size, drivers will still adapt their behavior during every simulation step. There are plans for adding a new car following model which allows reaction times above the simulation step size to be modeled ( http://sumo-sim.org/trac.wsgi/ticket/1151) 3) A normal distribution with expectation X may return any real value. However, we wish to avoid very low speedFactors so we always return values of at least 0.2. (The value in the wiki documentation was wrong and is now fixed). regards, Jakob 2014-04-22 12:03 GMT+02:00 Pieter Loof <[email protected]>: > Hi all, > > Just a few short questions to make sure that I interpret the vehicle > parameters correctly: > > 1. 'decel' is the maximum deceleration of vehicles, so the average value > will be lower. Suppose a vehicle drives towards the end of a traffic jam, > how large is the deceleration it will apply compared to this maximum value? > 2. 'tau' is the reaction time. Suppose we have simulation steps of 1 second > and a tau of 0.8, are vehicles then able to start reacting on a fraction in > between two simulation steps? > 3. 'speedDev' is the deviation for drawing a desired speed factor from a > normal distribution. The documentation says "The resulting values are > capped at 0.1 to prevent extreme dawdling." I don't understand this > sentence, can someone explain this? > > Best regards, > Pieter > > ------------------------------------------------------------------------------ > Start Your Social Network Today - Download eXo Platform > Build your Enterprise Intranet with eXo Platform Software > Java Based Open Source Intranet - Social, Extensible, Cloud Ready > Get Started Now And Turn Your Intranet Into A Collaboration Platform > http://p.sf.net/sfu/ExoPlatform > _______________________________________________ > sumo-user mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/sumo-user > ------------------------------------------------------------------------------ Start Your Social Network Today - Download eXo Platform Build your Enterprise Intranet with eXo Platform Software Java Based Open Source Intranet - Social, Extensible, Cloud Ready Get Started Now And Turn Your Intranet Into A Collaboration Platform http://p.sf.net/sfu/ExoPlatform _______________________________________________ sumo-user mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/sumo-user
