Talk:Proposed features/gross weight

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Good for me, in Italy this sign is used to much.

underscore usage

Resolved: The proposal has been reworked, the new tags do not have an underscore.--Martinq (talk) 18:46, 3 July 2013 (UTC)

To me, maxgross_weight looks really odd. Wouldn't it be better to use maxgrossweight (and grossweight for consistency)? -- Eckhart (talk) 10:09, 23 June 2013 (UTC)

+1 Rjw62 (talk) 07:34, 25 June 2013 (UTC)

Agreed. We shouldn't be combining underscores and empty strings for separation. Either max_foo_weight, or maxfooweight please, but no horrid combinations of both systems. I slightly prefer the latter. --achadwick (talk) 16:01, 26 June 2013 (UTC)

Bad example?

Resolved: The example has been replaced by a "real world" example. --Martinq (talk) 18:47, 3 July 2013 (UTC)
Example: hgv:conditional = delivery @ (gross_weight<5.5) - HGVs with a gross weight below 5.5t are allowed to use the road for delivery. Typically used in connection with hgv=no, which disallows entry for HGVs in any other case.

I'm not sure this is a good example. I don't know of any sign where permissions depending on gross weight exclude the upper bound (and treating bounds correctly is important for gross weight). -- Eckhart (talk) 10:19, 23 June 2013 (UTC)

You are right, it is a bad example. But not just for the reason you stated, also because maxgross_weight=5.5 and hgv=delivery express the same situation without conditional. There are some conditional-dependent real world example in my area, I will pick one of these.--Martinq (talk) 18:21, 23 June 2013 (UTC)
Changed the example, used a real world example requiring gross_weight and which cannot be expressed without conditional restriction.--Martinq (talk) 19:10, 23 June 2013 (UTC)

Changing the current usage of maxweight (in countries where most signs refer to the gross weight)

Resolved: maxweight remains as it is, but it should be stated that the meaning is ambiguous.--Martinq (talk) 19:53, 3 July 2013 (UTC)

As far as I can tell, most weight restrictions on UK roads are actually on the gross weight. I don't know about other mappers, but I've been blithely tagging them with maxweight=*. (I also wasn't aware that the weights inside the lorry on signs only applied to HGVs, but that's another matter.) Assuming that this practise is widespread, I think it's going to be problematic to essentially redefine maxweight now to mean just the actual weight. There would be much confusion as to whether a particular maxweight tag is using the new definition (and hence means actual weight), or is a hangover from before we have a gross weight tag (and hence refers to the gross weight instead). It therefore might be better to keep maxweight=* as a generic unspecified weight limit, and have a new tag that specifically refers to the actual weight, in addition to the new tag that specifically refers to the gross weight. -- Rjw62 (talk) 07:42, 25 June 2013 (UTC)

Me too! Given that weight and maxweight can refer to either the actual weight or GVWR already - it's literally whatever's written on the sign in most cases! - we shouldn't be redefining the existing database meaning of the tag. IMO we should keep a generic unspecified means of capturing the weight which doesn't require a novice mapper to know the ins and outs of weight limiting schemes around the world, or even what the default is in their country. The number of these schemes, and the fact that they can combine makes the picture exceedingly complex.
There is a specific use case here which must be addressed: that of a novice mapper who a) does not understand the distinction between all these weight ratings, b) sees a sign which does not state which rating is meant, c) is unaware of the "default" meaning in their jurisdiction, and d) wishes to map it anyway. It's useful to capture the numeric data regardless of precise meaning along the {axle | trailer | combined | vehicle} or {actual | gross} axes. More experienced mappers or data consumers can quietly convert the raw value to something with more explicit meaning based on their better knowledge after it's been captured.
In short, keep it simple; keep the existing meanings of weight and maxweight please (even if these are imprecise statements). Let's not be elitist: we need to encourage everybody to contribute.
--achadwick (talk) 15:31, 26 June 2013 (UTC)
I do no longer intend to redefine or change the meaning of 'maxweight'. Since we have 50,000+ uses, I plan to keep the definition (and the wiki page) as it is. But I propose to add a section which explains why the tag is ambiguous and that is no longer recommended for tagging vehicle related restrictions (and a reference to the more precise keys that can be used).
It is an open question if this recommendation is for all countries - or if for some countries can continue using 'maxweight', because only one type of weight limit is used (and therefore the meaning is always clear).--Martinq (talk) 19:51, 3 July 2013 (UTC)

Too limited?

Don't we need to cover two or more axes of information here, and also be able to say a lot more when we have our Expert Mapper™ hats on?

  • Where, or on what the weight is being measured: {axle|frontaxle|rearaxle|trailer|vehicle|combined|...}
  • Vehicle state: {laden|kerb|dry|...}
  • How the weight should be determined: {gross|actual|...} - e.g. by looking at the vehicle specifications for maximum operation weight, or by going to a weighbridge and measuring it.

A grammar like [max][<how>][<state>][<what>]weight suggests itself for generating the keywords here. But I'm unclear on the precise distinctions and splits between the axes; the list above is probably incorrect. Anyone a real expert on these things?

--achadwick (talk) 15:58, 26 June 2013 (UTC)

Yes, it is limited -- intentionally! The proposal is not intended to solve any potential weight tagging in the future ("universal weight tagging schema").
Schema: I have revised the proposal and somehow there is a kind of scheme in the tags (e.g. '...rating' is used to identify weight values that can only be found in documents). But the tag length should remain reasonable, which required some concessions in the tag naming.
If there is a real demand for further weight limits by an individual or a group of mappers (e.g. dry/crub...), a separate proposal should be made. My proposal addresses a personal need in my near environment plus a need of other mappers according to recent discussion on mailing lists and the wiki (it is not the first time that the issue with the different 'weight' meanings was discussed).--Martinq (talk) 19:41, 3 July 2013 (UTC)

Different sign/different weight meaning

I think we don't need gross_weight, or i don't see the problem. This sign Zeichen 262.svg says maximum weight. And we will tag this as maxweight=5.5
For gross weight, there is a different sign: the white additional sign like this Zusatzzeichen 1052-35.svg. We find it only with a main sign, or the weight is in the symbol UK traffic sign 622.1A.svg. And how will we tag this? Zeichen 253.svg+Zusatzzeichen 1052-35.svg hgv:conditional=no @ (weight>7.5) or hgv:maxweight=7.5. So all tags with :conditional and :maxweigth, or better all tags without the simple maxweight=* are grossweight.

The biggest downside of gross_weight is: Most mappers don't know the difference, but they can tag the sign correctly by this scheme. So we can know which weight is correctly by watching the tagging. --MasiMaster (talk) 18:24, 2 July 2013 (UTC)

While I would love the idea that 'weight' in conditionals always mean the rated weight (gross weight prior rework of the proposal) and that all maxweights always express a limit with sign Zeichen 262.svg: Sadly it was neither done this way in the past nor does it work in the future, since additional panels can (and do) refer to the actual weight. Additionally, be aware of your view has a regional bias. It is sadly fact that nobody can retrospectively identify or decide if the 50.000 uses of maxweight really describe actual weight limits. Therefore the value of maxweight for any data user is very low.
Since redefining the meaning of 'maxweight' is not possible due its inconsistent use in the past, all we can do is to replace the ambiguous 'maxweight' tags with more precise tags over time and make people aware why the simply 'maxweight' is not sufficient.
About casual mappers: They typically use either templates/presets in the editor or simply lookup a road sign table, thus it is very likely that they will pick the correct tag (for the road sign they have seen) in the future.--Martinq (talk) 19:23, 3 July 2013 (UTC)
I agree that now are both signs are tagged with maxweight. But first I guess that the Zeichen 262.svg will take over 80-90% of this cases. Second there is no big difference between these both signs, so it is not very bad. The danger of wrong tagging could be higher with the new tags. So better we can change the (wrong) others to the conditional-scheme.
Or do you want change all actual maxweigth=* into maxweigtht_the_old_one=*, and add only the checked back to the original maxweight-tag?I still think that grossweight don't work, because no mapper knows the difference between the signs! Back-engineering from tag to sign and to the meaning will work. --MasiMaster (talk) 22:54, 28 November 2013 (UTC)
First: There is a major difference in the meaning of the signs, especially if you drive an unloaded truck or bus.
Second: You probably generalize the frequency signs from your environment to global scale ("local bias"), for example in my environment the rate of signs is exactly opposite. So what seems reasonable in your local area does not work in other regions.
Fact is: 'maxweight' has been used for all different types of weights on a non-local scale. This fact is also a result of discussions so far. So assuming something about the meaning of existing 'maxweight' tags is dangerous. All it tells us: There is a weight related limitation, but we don't know the exact type. Whenever you find an old 'maxweight' it makes sense to do a survey and find out what type it really is and then add the exact type. For potential data consumers the exact type of weight limitation is essential, otherwise the data is of limited use.--Martinq (talk) 08:18, 29 November 2013 (UTC)

example with 5,5t

In Poland, Vorschriftszeichen 9c.svg is a sign B18 and means that vehcle actual weight >5,5t cannot use the road. But if its vehicle with a trailer (5t each) and combined weight is 10t then it cannot use it also.

It is possible that Poland deviates here from the European agreement as well as from the Vienna convention, the proposal explicitly states that country law can differ. I cannot prove the statement. If the sign also applies to combinations in Poland as you say, then maxgcw would be the right tag. Is it explicitely stated that it applies to combinations (truck+trailer) or your conclusion/interpretation? --Martinq (talk) 16:12, 21 September 2013 (UTC)
Right, in the convention its only 'vehicle', our meaning of the sign is vehicle or combined vehicles laden mass. We would rather stick with maxweight. (sign b18) --przemas75 (talk) 09:23, 22 September 2013 (UTC)

And from the table, example 2. If there is a specific sign with tonnage, we follow vienna rules, so it is not maxgcwrating:goods=X but maxgcwrating=X (all vehicles and combined vehicles) with hgv=no of course.

You mean Poland doesn't follow the Vienna rules, because convention says: The sign means "no entry for goods vehicles", any weight as inscription or additonal panel applies to the goods vehicles only (no entry for goods vehicles with weight rating>X). This can only be tagged with maxgcwrating:goods, because a separate maxgcwrating=X also applies to busses, agricultural vehicles, etc whilst the convention sign does include them or adds any restrictions to non-goods vehicle. Also take into account that in Europe goods vehicles have been harmonized to three classes (M1, M2, M3), but hgv are only M2 and M3, so double-check your hgv=no assumption (if M1 is included, goods=no is correct).--Martinq (talk) 16:12, 21 September 2013 (UTC)
You're right, it should be more precise. In fact our sign puts some more restrictions, not only hgv(agriculture ie.). We agreed it shall look like: maxgcwrating:hgv=x (is it n1/2/3 or m1/2/3 classes? i think the primer?). But can you put some examples of the vehicles (combined unit) to have tag maxgcwrating, i mean, why dont we use maxweightrating? This way we could invite only one new tag. --przemas75 (talk) 09:23, 22 September 2013 (UTC)

Not clear

I don't like that a few shortcuts and few full names. We have in Poland system: max(short)weight[rating] Example:

gross vehicle weight rating - maxgvweightrating

gross combination weight rating - maxgcweightrating

gross trailer weight rating - maxgtweightrating

and mass values without rating:

maxgvweight

maxgcweight

maxgtweight

All tags have "weight" so people know what it is even if they do not understand (gc,gv,gt).

Dotevo (talk) 14:53, 28 September 2013 (UTC)

Your idea is good, but sadly some keys are already in use, thus I cannot scrap the original proposal. But I updated maxgcw to maxgcweight and maxgcwrating to maxgcweightrating, since the maxgcw and maxgcwrating didn't have any significant use so far. So the most frequently used "new weight" tags in Poland are consistent with the proposal now. For the two other tags I documented your alternative "Poland" schema and included taginfo.
Is there any reason why you invented "gtweight"? Why does maxgvweight:trailer and maxgvweightrating:trailer not work for you?--Martinq (talk) 23:00, 11 November 2013 (UTC)


Unladen

What to do with unladen weight? https://www.openstreetmap.org/way/167262167 --Karussell (talk) 10:50, 1 November 2015 (UTC)

It is not covered by this proposal, you have to create you own tag and/or proposal, for example maxunladenweight.--Martinq (talk) 19:59, 2 November 2015 (UTC)