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Complicated highway ramp fixup advice.

Posted: Thu Jan 10, 2013 4:29 am
by mikenh06
I'm a new map editor that fixed an issue I encountered today. Given it was kind of complicated, I figured I'd consult to see if I got it right.

If you look here: https://www.waze.com/editor/?lon=-71.45 ... 9,31591364

The two highlighted segments used to be drawn as one segment, which matches the physical layout of the road. However, a result of this is I was routed off the freeway onto the ramp, then followed the path through the interchange that put me back on the freeway. Since this path never touches a surface road, I think it's technically legal, but it's very poor routing. (And in over a decade of commuting through there, I've never seen a case where following that particular path would buy you any time at all.)

So my solution was to parallel that short piece of ramp with one segment of road for each of the two sides that traffic enters. At the point I put a juncture to join the traffic together, I disallowed the traffic coming off the freeway from following the left lane that enters the ramp system that eventually puts you back on the freeway.

Comments?

Complicated highway ramp fixup advice.

Posted: Thu Jan 10, 2013 5:32 am
by AlanOfTheBerg
I don't really like how it looks, but technically, it may be the best way to prevent ramp-to- ramp routing.


iOS and Tapatalk have conspired to screw up this post.

Re: Complicated highway ramp fixup advice.

Posted: Thu Jan 10, 2013 2:59 pm
by cdombroski
Part of the problem might be that these two segments don't share the same name. My understanding is that waze will avoid ramps when routing between two segments of highway with the same name. Changing the southern segment's name might be enough to prevent routing through the ramp without the ramp doubling trick.

Complicated highway ramp fixup advice.

Posted: Tue Jan 15, 2013 1:18 am
by fvwazing
Yes - but you do not have to see it in the client.

Re: Complicated highway ramp fixup advice.

Posted: Sun Jan 13, 2013 11:07 pm
by gerben
The only problem with these is that it is difficult to force a Keep Right for the cloaver leaf because there is only one way to go from the left incoming lane. In NL we add short stubs, solely to force a keep right:

https://world.waze.com/editor/?lon=6.02 ... =184468816

Re: Complicated highway ramp fixup advice.

Posted: Tue Jan 15, 2013 12:21 am
by jondrush
That is an ugly kludge.

Re: Complicated highway ramp fixup advice.

Posted: Fri Jan 11, 2013 2:04 am
by mikenh06
Possibly. That will require someone else to fix because the highway is locked at level 5.

Also, that is the state line and the highway really does change names right there :) It could probably be fudged for a few feet to solve the issue though.

Re: Complicated highway ramp fixup advice.

Posted: Fri Jan 11, 2013 10:01 am
by skbun
xplayman wrote:I had to stare at it for 5 minutes before I realized this was a similar issue I ran into with a highway service road that ran alongside the highway. It would weave people in and out of the highway all of the time. I think the problem is that ramps don't have speed properties like highways and streets do. So my solution to solve the roads along highways problem was to make those roads (in this case a ramp) that runs along a highway into a Service Road.

The routing might work better if you change that inner ramp that runs along the highway into a Service Road but you may want to repost this problem or link to this thread in a new post using Subject: "Level 5 Needed... [Where]"
Ramps DO have speed data, just as freeways themselves do. The issue is that at certain peak rush hour times, Waze will detect that doing an off-and-on from a ramp and on again is actually faster than bumper to bumper traffic on the freeway, but it's not really a reasonable way to travel.

A service road, IIRC, has the same general penalty as a 'street', which isn't really enough to prevent this. 'Parking lot roads' and 'private roads' have large enough penalties to prevent routing - but if you make the whole slip road one of THOSE, then the exit itself won't work for ANYBODY.

I've seen different approaches to the 'prevent off-and-on the slip road' problem.
The one you've reasoned out is what I personally call a 'crossover'. Here's an already implemented example in action.
https://www.waze.com/editor/?zoom=8&lat ... FFTFTTTTFT

The idea is, although the slip road is physically one road, there are two paths. One is coming onto the freeway (and both 'onto the other exit' or 'onto the freeway' is allowed, and the other is denied the off-and-on. I call it the crossover because, well, you see it. Just before the last exit, the paths cross. It's basically what you came up with on your own, but here you can see how a more experienced editor did it. You'll notice angles used at the turn points; those will determine what the TTS says for map instructions.

As you're just starting out as an editor, I'd try this one out using a crossover and turn restriction like in the example, and see how you do with it. You can look into other ways to do it later if you want.

Best of luck!

Re: Complicated highway ramp fixup advice.

Posted: Fri Jan 11, 2013 4:01 am
by xplayman
I had to stare at it for 5 minutes before I realized this was a similar issue I ran into with a highway service road that ran alongside the highway. It would weave people in and out of the highway all of the time. I think the problem is that ramps don't have speed properties like highways and streets do. So my solution to solve the roads along highways problem was to make those roads (in this case a ramp) that runs along a highway into a Service Road.

The routing might work better if you change that inner ramp that runs along the highway into a Service Road but you may want to repost this problem or link to this thread in a new post using Subject: "Level 5 Needed... [Where]"