[New Page] Median U-turn intersection

Moderator: Unholy

Re: [New Page] Median U-turn intersection

Postby CBenson » Wed Mar 19, 2014 2:20 pm

I think this would make a good wiki page. Maryland has taken to implementing many Restricted Crossing U-Turn (RCUT) / Super-Street Median Crossover intersections and I do believe that the guidance for the U-turn roads should be similar. Currently the U-turn roads are typically not typed as ramps here (because it conflicts with the wiki so they get changed when they are made ramps). They also aren't typically configured to give the second turn left instruction. But if those in Michigan that have more experience with these types of U-turns have determined that the second instruction is helpful, I don't see an issue with including it on RCUT intersections as well.
Regional Coordinator: Mid-Atlantic, US
Verizon, Nexus 6, Android 6.0.1, Waze 4.7.0.902
CBenson
EmeritusChamps
EmeritusChamps
 
Posts: 10330
Joined: Wed Nov 03, 2010 9:13 pm
Location: Crownsville, MD, US
Has thanked: 1055 times
Been thanked: 2353 times

Re: [New Page] Median U-turn intersection

Postby CBenson » Wed Mar 19, 2014 3:55 pm

kentsmith9 wrote:Is there an RCUT page in development by anyone? I did not see "RCUT" in the Main or User namespaces, so I assume not.

There isn't one that I'm aware of. They are mentioned on the page you referenced as a variant of the Median U-Turn Intersection. Essentially, they do not allow the straight movement of the secondary road through the intersection. Example here. Seems to me that the U-Turn roads should be treated similarly for the "MUTI" and the "RCUT," and thus the requirements for the U-Turn roads can be set forth in this one wiki page.

kentsmith9 wrote:If we need a Ramp there for the right reasons, then we should update the Wiki. Do we need a separate thread just on Where to allow Ramps?

I don't think we need a separate thread. These intersections are simply an exception to the guidance not to use ramps for at grade connectors.
Regional Coordinator: Mid-Atlantic, US
Verizon, Nexus 6, Android 6.0.1, Waze 4.7.0.902
CBenson
EmeritusChamps
EmeritusChamps
 
Posts: 10330
Joined: Wed Nov 03, 2010 9:13 pm
Location: Crownsville, MD, US
Has thanked: 1055 times
Been thanked: 2353 times

Re: [New Page] Median U-turn intersection

Postby CBenson » Wed Mar 19, 2014 6:23 pm

kentsmith9 wrote:I think wherever we say there is an exception, we need to describe why we would do it in one place and not another. For example the [[At-grade connectors]] page says why to use ramps there so people understand the reason. In the U-turn page we just need to do the same thing to explain the "why." Part of the process of teaching people to fish. :D

Doesn't the U-turn page do that with the following:
Road Type: RAMP
Although this departs from traditional rules for at-grade connectors and for use of the ramp road type, it hides the instructional street name in the client. It is close to the exception stated on the at-grade connector page, however, in that a MUTI is a signed--though unnumbered--exit from the current direction of travel on a roadway.

Otherwise, you get other workarounds like this segment.
Regional Coordinator: Mid-Atlantic, US
Verizon, Nexus 6, Android 6.0.1, Waze 4.7.0.902
CBenson
EmeritusChamps
EmeritusChamps
 
Posts: 10330
Joined: Wed Nov 03, 2010 9:13 pm
Location: Crownsville, MD, US
Has thanked: 1055 times
Been thanked: 2353 times

Re: [New Page] Median U-turn intersection

Postby CBenson » Fri Mar 21, 2014 11:14 am

I'll just note, before this discussion I had no idea what a J-turn/Reduced Conflict Intersection (RCI)/Restricted Crossing U-Turn Intersection (RCUT)/Super-Street Median Crossover was called. I have driven them but had never heard them called anything. I had to search for a name before I realized the intersections referred to in the draft as variants were what I was thinking of.

The only term I knew before this discussion was "Michigan Left."
Regional Coordinator: Mid-Atlantic, US
Verizon, Nexus 6, Android 6.0.1, Waze 4.7.0.902
CBenson
EmeritusChamps
EmeritusChamps
 
Posts: 10330
Joined: Wed Nov 03, 2010 9:13 pm
Location: Crownsville, MD, US
Has thanked: 1055 times
Been thanked: 2353 times

Re: [New Page] Median U-turn intersection

Postby CBenson » Thu Apr 10, 2014 2:26 am

Super-street/RCUTs should be addressed, so the content should not be exclusively about MUTIs.
Regional Coordinator: Mid-Atlantic, US
Verizon, Nexus 6, Android 6.0.1, Waze 4.7.0.902
CBenson
EmeritusChamps
EmeritusChamps
 
Posts: 10330
Joined: Wed Nov 03, 2010 9:13 pm
Location: Crownsville, MD, US
Has thanked: 1055 times
Been thanked: 2353 times

[New Page] Median U-turn intersection

Postby davielde » Fri Mar 21, 2014 1:24 am

sketch wrote:I agree with qwaletee, the Wiki should be written in such a way that newbie editors can understand it and aren't scared off by it. "Michigan left" was changed to "MUTI" in the first place by a Michigan-based editor (hey, davielde) in order to make it nationally applicable, but perhaps those who live in Michigan don't realize that "Michigan left" is a common name nationwide too.

We're too busy enjoying Pure Michigan to really pay attention to outsiders.

MUTI was selected to make it more universal, but it also seemed to make it easier to include all of the variants, many of which had cool names with acronyms too. MUTI was also chosen as the the primary synonym for at least two other reasons:

1) Every word in "Median U-Turn Intersection" stresses what it is. The maneuver occurs at major *intersections* and not just any unsigned crossover, and it involves a split road median.

2) "Michigan Left" is a term that seems to have been coined by a journalist twenty years after it originated, and it still is not found in much MDOT literature. Median U-Turn Crossover and Median U-Turn Intersection is.

If MUTI is too technical, I'm fine with adopting "Michigan Left" or "Michigan Left Turn" as long as we're *certain* that it doesn't cause confusion nationally, and as long as enough emphasis is placed on "intersection" and "median" elsewhere in the article.
[ img ]
CM: USA
SM: Michigan, Vermont
AM: Ann Arbor, MI & Thunder Bay, ON
WME Michigan
davielde
 
Posts: 1219
Joined: Tue Sep 17, 2013 2:01 pm
Location: Michigan, USA
Has thanked: 461 times
Been thanked: 759 times

Re: [New Page] Median U-turn intersection

Postby davielde » Fri Mar 21, 2014 12:19 pm

CBenson wrote:I have driven them but had never heard them called anything.

Give it twenty years, and there will be nicknames locally used for those too :-)
I suppose "Michigan Left" really is best then, with possible continued mention of at least some of the variants on the page itself. True synonyms like "Arizona Parkway" or "Boulevard Turnaround" could probably be removed altogether and just exist as redirects.
[ img ]
CM: USA
SM: Michigan, Vermont
AM: Ann Arbor, MI & Thunder Bay, ON
WME Michigan
davielde
 
Posts: 1219
Joined: Tue Sep 17, 2013 2:01 pm
Location: Michigan, USA
Has thanked: 461 times
Been thanked: 759 times

Re: [New Page] Median U-turn intersection

Postby davielde » Fri Mar 21, 2014 3:55 pm

MeridianHills wrote:One thing that could be added into the wiki for the new Median U-Turn Intersection
https://www.waze.com/editor/?lon=-86.06 ... 01&env=usa
MUTI's where the turn around segments have cross traffic from the left & right.

That may not be a bad idea, particular since there are a number of odd situations that may arise where the Michigan Left instruction does not apply to all traffic crossing the physical segment. In that case, there is sometimes a need for a "logical" separate segment.

Here's a fairly common one where the median crossover serves as the entrance for an intersecting street, where it was important to preserve the turn instruction with the proper street name, and I've come across two or three other things similar to it.

To eliminate as much confusion as possible, perhaps we could have a small "guide" with a table and sample pics for different configurations, similar to what is done for the Road Type Guide on the roundabout page.
[ img ]
CM: USA
SM: Michigan, Vermont
AM: Ann Arbor, MI & Thunder Bay, ON
WME Michigan
davielde
 
Posts: 1219
Joined: Tue Sep 17, 2013 2:01 pm
Location: Michigan, USA
Has thanked: 461 times
Been thanked: 759 times

Re: [New Page] Median U-turn intersection

Postby davielde » Fri Mar 21, 2014 7:37 pm

qwaletee wrote:The naming seems there to maintain the illusion of left turn at the previous intersection, but I don't know how much good it does. Especially since it might sometimes result in an announcement about the cross street (your real target) as you approach that cross street. That might seem like you are being asked to make an illegal turn.

The navigational guidance cleanly matches whatever you will be routed onto. If Waze is going to route you onto the illusory "left" (left-left-right) turn for the main intersecting street that you've already passed, you'll see and hear that "ramp" instruction every time. If Waze intends to route you onto the street that intersects at the u-turn crossover itself, you'll just see and hear "turn left at [street]". The segment data may be polluted if you happen to "snap" to the wrong segment. Even in that case though, the dual segments are so close that there is not enough distance where a recalculation resulting in a bad instruction would occur. I haven't seen a "restricted turn not allowed" MP from that setup either, which may potentially occur if Waze has you on the wrong segment thinking that the continuation is the only allowed turn, when in fact you turn left.

Because of the added risk of crossing all of the lanes to get to the street, the vast majority of these Michigan Left turnovers do not line up with another street, so the full turnaround is the only option. IMO it is more of a bonus to the drivers trying to get to the other street or parking lot when they do line up (unless they get hit trying to cross a few lanes of traffic...). Along major roads, more and more of these setups where drivers have the two options are being controlled by traffic lights, by the way.

qwaletee wrote:Trying to meet the convention is forcing you into this weird dual segment, which is introducing ugliness to save purity.

It may be ugly from an editor standpoint, but the segments are so close together on the app even at the most detailed zoom level that they are indistinguishable with all themes except the Map Editor. In that case, there is only a small sliver of white under the green. I think that the benefit of the dual segment in reducing confusion for either outcome outweighs any ugliness.
[ img ]
CM: USA
SM: Michigan, Vermont
AM: Ann Arbor, MI & Thunder Bay, ON
WME Michigan
davielde
 
Posts: 1219
Joined: Tue Sep 17, 2013 2:01 pm
Location: Michigan, USA
Has thanked: 461 times
Been thanked: 759 times

Re: [New Page] Median U-turn intersection

Postby davielde » Fri Mar 21, 2014 9:57 pm

Here's the link to the section of the Michigan wiki under discussion just so we don't have to go a few pages back on the thread. This is part of the struggle of bringing a localized maneuver to the national level.

We need to use an example that doesn't have the main road name the same as the street that happens to intersect at the Michigan Left. :)

qwaletee wrote:There are no signs there that I can see, so you're not "following the BGS," which is how we usually name ramps. We make exceptions where there are multiple splits or crosses in short succession, and the readouts could become confusing. Here you are using an "implied" secondary name of "to Wilson."

As the wiki states, "proper signage should be in place. Depending on what entity maintains the road, however, the quality of signage will vary". If the state DOT maintains the road, there may be and usually is a "big" green sign. If a city, county or township maintains it though, you'll see a little green sign. In this case, here is the sign for the Michigan Left from Jackson onto Wagner, the street you already passed. It's not a sign for "Jackson Plz" because those continuations are not signed here in Michigan. Only the main cross street for the Michigan Left is. And signage can be a lot worse than this... Anything unsigned though would not meet the criteria and would not be a Michigan Left. Also, when multiple splits or crosses are in succession, they are not Michigan Lefts. Only the signed one for the major intersection would be.
[ img ]

The page also states that it is against accepted usage of the ramp road type (at least at that time), but it is to hide the instructional name in the app. "to Jackson Rd E / to Wagner Rd S" clutters the map, and anyone seeing it would laugh. Most "ramps" exist to carry instructions. They don't have "street" names themselves.

qwaletee wrote:The chief issue you raise with an unnamed segment here is that it would say "left to SAME ROAD YOU ARE ON," though that could be mitigated by naming the split roadway with E and W qualifiers. Alternatively, the segment could be named U-turn, or a combined segment could be U-turn / Jackson Plz.

By virtue of the turn restriction on the left turn, the current unnamed segment only facilitates travel onto Jackson Plz, not Jackson Rd E to get to Wagner Rd S. The Michigan Left segment is named so that you don't get the left onto the same road you are on though. You get left onto the same road in the opposite direction. Using "U-turn" would also be instructional in that you never see a sign (in Michigan) for a "u-turn". That's because it's a localization issue. Here, a "u-turn" is illegal because it implies you are turning in the middle of a road where there is no median in order to go the opposite direction. A Michigan Left involves a "median u-turn" or "turnaround", but those are also phrases you will never see on a sign here.

EDIT: Actually, u-turns are legal in Michigan in any area where a city, township or village does not adhere to the state's Uniform Traffic Code, but they are so heavily restricted by signage at almost every intersection that everyone here commonly believes they are illegal.
[ img ]
CM: USA
SM: Michigan, Vermont
AM: Ann Arbor, MI & Thunder Bay, ON
WME Michigan
davielde
 
Posts: 1219
Joined: Tue Sep 17, 2013 2:01 pm
Location: Michigan, USA
Has thanked: 461 times
Been thanked: 759 times

Next

Return to Wiki Updates and Discussion

Who is online

Users browsing this forum: Google Feedfetcher