Proposal talk:Kerb=regular

From OpenStreetMap Wiki
Jump to navigation Jump to search

Other values

Please considering adding in all of the top kerb=* values to present a more complete picture.Glassman (talk) 14:39, 1 August 2020 (UTC)

I added taginfo values for all documented tags now. --Supaplex030 (talk) 20:28, 1 August 2020 (UTC)


To distinguish higher kerbs (eg >15cm) than normally-raised ones (eg ~10-15cm), something like kerb=high (need to check its usage) could be more direct. From an opposite perspective, a new value like kerb=semi-rasied could be used for moderate kerbs (eg ~5cm) that aren't "lowered".

kerb=high Header text
Usage not checked Example

-- Kovposch (talk) 17:18, 1 August 2020 (UTC)

I think that misses the functional purpose of this categorization and should better be expressed with kerb:height=* (already in use). And from my experience in curb mapping, I would say that this distinction leads to more subjectivity and therefore worse data. But from a structural perspective it's easy to distinguish the "main types" lowered, regular and raised. --Supaplex030 (talk) 20:28, 1 August 2020 (UTC)
The definition of a raised kerb is one that > 3cm high and regular kerb between 10 and 15 cm. Both are basically the same thing which means that they are inaccessible for people in wheelchairs with the obvious exception of wheelchair athletes. There are already more than 11K kerb=rasied in use. kerb=regular will only confuse mappers and data consumers. I agree with Kovposch that using kerb:height=* is a better way to define a kerb.Glassman (talk) 22:43, 1 August 2020 (UTC)

only for nodes?

I am not sure this was intentional but you seem to suggest the tag kerb=regular only for nodes? What about ways? —Dieterdreist (talk) 23:53, 1 August 2020 (UTC)

Thanks for the hint - I made it more clear now. I mentioned the use on ways in the "Applies to"-section but it was confusing. Of course it can be used on ways (as usual with other kerb tags). I merged "Tagging" and "Applies to" section as they described the same.--Supaplex030 (talk) 09:40, 2 August 2020 (UTC)

A poor value choice.

The word regular can be taken as what is normal in a particular area. Curb heights can be set to reflect the flash rainfall water that should be quickly drained from roads. In Sydney, Australia this may be a height of 15 cm, but in Broken Hill, Australia this can be 25 cm reflecting the flash rainfalls of the climates. It maybe better to specify the actual height kerb#kerb:height=*. Warin61 (talk) 01:41, 2 August 2020 (UTC)

I agree that in these cases it maybe better to specify the actual height with kerb#kerb:height=* - but in most regions it is not necessary and (as described in the proposal) is much more difficult to measure (especially in large-scale surveys). It would result in less curb information being collected (since only a few have a ruler with them when mapping :) --Supaplex030 (talk) 09:47, 2 August 2020 (UTC)

Thought experiments

I live in a neighborhood (in the US) where there are only 15 cm kerbs (these are common everywhere in the city), and I have only ever seen an SUV (by law enforcement) or a pick-up truck (by a landscaper) attempt to drive over these. There might be a reasonable distinction based on the height of the undercarriage of a vehicle (for navigation). In both cases, overcoming these 15 cm curbs has involved the driver coasting until the front or rear wheels reach the curb, and then flooring the acceleration pedal briefly. Escallic (talk) 14:41, 21 August 2020 (UTC) Update: I made a mistake! The curbs I was referring to are actually only 15 cm, not 160 mm. These would be on the upper end of normal. I changed the above. Whoops! Update: Sorry, that above should also probably read 'regular' as the proposal suggests. Both are good IMO. While 'regular' may refer to that which has a high frequency of occurrences (10-15 cm kerbs), 'normal' may refer to that which has a 25 mm margin of error from an accepted norm (125 mm), a global norm or a regional norm.

Meaningful Values

If the purpose is to make a distinction between normally raised kerbs and extra raised kerbs, as kerb=raised potentially means both, kerb=raised should be depreciated. Then we want (at least) two values. Or specify in the wiki "well over 3 cm" for kerb=raised. I think that's how it's used. kerb=standard or kerb=normal is probably more self explaining than kerb=regular (not completly sure). As kerb=raised is defined compared to normal, I would go for kerb=normal.

So kerb=normal and kerb=elevated or (IMHO better): kerb=normal and kerb=raised.

To the objection that normal depends on the usual maximal rain falls in the region, that's true but it doesn't change many things:

  • name is the name in the local language. The local language is defined in an englobing feature, typically a country: an name in France is in French as default_language=fr. So we could define default_normal_kerb_height=* for a town, a region, a country... It makes the life of the ordinary mapper ways easier.
  • scallability: it's obvious if a kerb is raised, normal, lowered or flushed. It doesn't prevent to add a specific measured kerb:height=* if you have time or an open data source.
  • by indicating normal/raised/lowered we indicate the purpose of the kerb. "Just" for rain falls, also a help for users to walk into or out a public transport, also a help for crossing a street (or the opposite, for cars to cross the side walk).

Another issue with the kerb=* key is that the shape/profile is mixed withth the height is the same key. --Nospam2005 (talk) 17:41, 30 August 2020 (UTC)

Lovely idea, but some suggestions

I really thing your idea is lovely, because I can't properly tag kerbs here in Brazil, where accessibility isn't the norm yet, and 'regular kerb' is the standard. English is not my first language, but to me, 'raised' means something higher than 'regular', which is higher than 'lowered' (and 'flush'), so I definitely agree that some distinction should be used.

Additionaly, I can't see any point to use height to define the category. It's not practical to measure every kerb, and every place has a distinct norm. height=* can be (and is already) used for that.

Personally, a basic distinction should be used, something like 'elevated' ' regular' 'lowered' and 'flush' (see other comments, much better than mine), without any connection with height, just related with the kerb and the street themselves. For heights, height=* already exists.

Regarding kerb=raised, I'm not sure what to do with them. Ideally, it should be deprecated, and everything already tagged should be revisited, splitting in 'elevated' and 'regular', but I don't think it's too practical either.

Anyway, I still appreciate your idea, and I approve the creation of this distinction. Raised is raised, not regular, and your rationale summarizes quite well the problem. Matheusgomesms (talk) 18:49, 30 August 2020 (UTC)

kerb=raised used for normal kerbs?

Has somebedoy used kerb=raised for normal kerbs? As the wikie states that it's for above normal kerbs it should not. And therefore no need to depreciate kerb=raised or worse to change it's current meaning, right? Then the wording should just clarify the current usage. --Nospam2005 (talk) 19:10, 30 August 2020 (UTC)

"Raised above the norm" of what? It could possibly be interpreted as relative to kerb=lowered in the context of crosswalks, as it already impedes movements. It's defined as >3cm. Even as an indicative figure, this still affects usage. Example includes "older kerbs". "Raised sufficiently to prevent traversal by wheelchairs, as well as an impediment to bicycles." and "Typically seen at bus stops to provide a level platform to enter bus" in Proposed_features/kerb are conflicting descriptions. The latter is a subset of the former. ---- Kovposch (talk) 04:40, 31 August 2020 (UTC)
Defining it relative to the sidewalk can be an issue when you consider low-level sidewalks, as raised by Talk:Key:kerb#"Double_sided"_kerbs. I also floated the idea of a "high" value above Talk:Proposed_features/kerb=regular#Motivation, for the reason of "high" and "low" level platform boarding terminology in transit. ---- Kovposch (talk) 04:44, 31 August 2020 (UTC)
It could possibly be interpreted as: the question is not if it possibly could be but if it is used as such in the database. The norm is here obviously standard kerbs not what is standard in non standard cases. The question is practical not theoretical.
I do agree that we have a conflicting description but due to the example of the level platform, IMHO the later (the restrictive version) is the right, logic one, compatible with the first part (above normal kerbs). So again, do some mappers in pratice use raised for normal kerbs? I doubt but I'm looking for people saying "yes I do". If not we can just reformulate the definition do avoid ambiguity. KISS --Nospam2005 (talk) 07:42, 31 August 2020 (UTC)

A possible solution

The proposal was rejected but the basic problem is mostly agreed. I see two possible solutions:

  • Deprecate the category raised and introduce two new values ​​to replace and differentiate it (eg "heightened"/"elevated" vs. "normal"/"standard"/"medium"
  • Keep the existing categories, accept that the term "raised" has so far included both normal and raised kerbs and merely introduce options to distinguish actually raised kerbs (elevated above (local) norm).

I am clearly in favor of the second solution: From the mapped cases I know and the prevalence of actualy raised curbs in real world I'm assuming that most of the curbs tagged with kerb=raised are not raised above the norm. So a first step towards a solution could be to make a recommendation to explicitly add kerb:height=* to exceptionally raised curbs (higher than ~15 cm/the local norm). This is an important addition for barrier-free routing - OpenRouteService already takes cerb heights/centimeter information into account for wheelchair routing. (We could also introduce a new Tag for this, but I will not take the initiative.)

A second step towards a solution could be to introduce kerb=kassel (or kerb=boarder?) for "Kassel kerbs" that are raised for reasons of accessibility (and not to prevent it), usually on bus boarders/public transport platforms. There is currently no way to differentiate. This new curb type could be tagged on public_transport=platform as well.

Whatever: The wiki should be cleaned up, as it contradicts itself in many places and does not appear up-to-date. I'll try it.--Supaplex030 (talk) 20:29, 6 September 2020 (UTC)

I checked about 20 cases, in all cases I could understand the meaning of raised: elevated for transport platforms or grass, normal for crossings. Maybe not a big deal to depreciate. Anyay it's the same work (adding a second tag or replacing the value of the first one).--Nospam2005 (talk) 20:57, 6 September 2020 (UTC)
No, if you filter all "raised" kerbs with kerb:height or height from the database (I can find 1281) or all "raised" kerbs with images, you can see, that most of them are 3-15cm ("normal") height.--Supaplex030 (talk) 06:14, 7 September 2020 (UTC) Edit: Only 14% are >15cm.
If you filter all "raised" kerbs with kerb:height or height you filter with an attribute making the main attribute (kerb) almost useless. That's one major reason of the rejection of your proposal. If you want to distingish, measure it was a common answer. --Nospam2005 (talk) 07:04, 7 September 2020 (UTC)
The distinguishing point of "Kassel kerb" is actually the rounded corner to align tyres, not its height. ---- Kovposch (talk) 06:47, 7 September 2020 (UTC)
What about kerb=boarder? (And: In this case, the accessibility function is actually more important than the height - but usually means an increase height.)--Supaplex030 (talk) 06:59, 7 September 2020 (UTC)