From: Matthew F. <mat...@vt...> - 2012-06-11 14:49:11
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I like (a) and (b). I especially like that a driver's deviation from the speed limit is constant throughout the simulation and not changing for every new link entered. Thanks, Matthew > -----Ursprüngliche Nachricht----- > Von: Daniel Krajzewicz [mailto:d.k...@go...] > Gesendet: Donnerstag, 7. Juni 2012 10:48 > An: sumo-devel > Betreff: [sumo-devel] request for comments on maximum speed extensions > > Dear all, > > I am currently working on speed limits in SUMO. Currently, each vehicle > has > an own max. speed, as well as each lane has a speed limit. > There are two issues which I would like to handle: > a) speed limits per lane may differ between vehicle types > b) vehicles drive sometimes faster than the allowed velocity. > > You'll find some ideas and notes on both changes, below. Kindly support > any > notes soon. > > > a) > We had once a discussion whether we should use OSM's speed definitions > which are resembled using a country code. I do not think that this is > exactly what we want. We would have to categorise the roads, would need > to > have databases of nation -> road type -> vehicle type -> speed. Both > forces > additional overhead, the only supplier of such data would be OSM and I > assumed the quality of OSM data as not reliable enough. > Instead, I would propose to add optional tgs within the lane definition > which describe speed limits for certain vehicle classes. For example: > <edge id="foo" from="foo" to="bar" priority="3" type="a"> > <lane id="foo_0" index="0" speed="15.00" length="593.45" > shape="6.55,2845.05 600.00,2845.05"/> > <lane id="foo_1" index="1" speed="15.00" length="593.45" > shape="6.55,2848.35 600.00,2848.35"> > <speedlimit vclass="bus" speed="10"/> > </lane> > </edge> > > Within the XML input, we'd need a further tag, probably, for lanes and > edge > which would define this value. I do not really have a good idea on > this, > especially when coming to edge splitting and stuff. > Also, we'd need to parse the information in the routers. > > For dealing within the simulation, it should be enough to modify the > MSLane's getMaxSpeed-method, introducing the vclass asking for the > velocity > as a parameter. The bad thing that we have to look up in a map, which > may > cost some time... But we probably have to live with it for the sake of > the > simulation's quality. > > > b) > The idea is to compute a vehicle's maximum desired velocity by: > > 1) take the maximum speed allowed on the lane > 2) Apply a vehicletype-based modification: > > speedFactorfloat >01the factor by which the driver multiplies the speed > read from street signs to estimate "real" maximum allowed speed > speedDev float > ≥00the standard deviation of the estimated maximum speed (see speed > factor) > divided by this speed. > 3) get the minimum of this speed and the vehicle's maximum speed > > Initially, we wanted to decide about a new speed everytime the vehicle > either a) turns or b) the max. velocity of a consecutive lanes changes. > After thinking about this, I'd say that this is too complicated - we'd > have > to keep the once determined velocities of not yet reached lanes > somewhere > in the memory, and the determination of "turns" would force additional > overhead. Instead, I would propose that every vehicle chooses a speed > modification factor based on the parameter described above and keeps it > forever. We can then simply multiply each lane's maximum velocity with > this > value. > > > > > sincerely, > Daniel > ----------------------------------------------------------------------- > ------- > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. > Discussions > will include endpoint security, mobile security and the latest in > malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > sumo-devel mailing list > sum...@li... > https://lists.sourceforge.net/lists/listinfo/sumo-devel |