John Smith wrote: > --- On Mon, 10/8/09, Lambertus <[email protected]> wrote: > >> Really, I'm no traveling salesman, but I lean towards >> defining routing classes for all the highway=* tags and add >> children to each of them for different situations (like >> surfaces, width, turns that cross the other lane, traffic >> lights etc) that add or subtract average speed or add >> penalty time (average speed penalties have no use on nodes >> like bollards or traffic calming). > > You could do this based on estimated m/s, a motorway at over 100km/hr is a > minimum of 28m/s, obviously if maxspeed is available that could nail it down > much better. > That's indeed how Gosmore works, the routing rules specify what the average speed of a certain road is (usually a few km lower than the maxspeed).
> Lots of unsurfaced roads are maxspeed=100 but you wouldn't be able to sustain > that all the time, I'd say a 30% hit at a guesstimate. > Legal speeds and practical speeds are usually not in relation with each other when talking about the unsurfaced roads. On the other hand, I've driven some South African 'washboard' dirt roads with a rental car and could not sustain more then 40km/h while the windows were shaken loose in their hinges. But the typical 4WD 'bakkies' pickups roared past us at full speed.... So average speed is difficult to determine for such roads unless you differentiate between 4WD and luxury cars. > calming devices drop you to 15km/hr or there abouts. > Yes, but as they are often represented as a node in OSM, giving them an average speed is meaninless. A time or point penalty seems more suitable. _______________________________________________ dev mailing list [email protected] http://lists.openstreetmap.org/listinfo/dev
