Talk:Cheltenham Standard
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Contents |
Background
Tagging - draft
Some thoughts on a tagging scheme, given that this standard is becoming more important now. Howsabout
| Tag | Remarks | Cheltenham colour |
|---|---|---|
| cyclability=1;2;3 | "Quiet roads with little traffic and low traffic speeds" | Yellow |
| cyclability=some_1;2;3 | "Through routes with moderate traffic and low speeds" | Green |
| cyclability=2;3 | "Busy roads, including A or B roads, where road design is traditional and does not lead to excessive speed" | Blue |
| cyclability=some_2;3 | "Busy principal roads, perhaps with some HGVs" | Red |
| cyclability=3 | "Fast, busy roads with frequent HGVs" | Purple |
This is all expressed with reference to the UK's National Standards for Cycle Training levels of proficiency. We should avoid using a colour-based approach when tagging for OSM: renderers should be free to do their own thing.
The national mapping standard's blurb actually uses the term "Cyclability" and refers you to TRL research to understand what that concept means.
Questions/Discussion
- Do we need an "nsct" in there to express whose concept of cyclability we're talking about? --achadwick 12:48, 29 January 2009 (UTC)
- Should the tag key be "nsct_levels", perhaps? --achadwick 12:48, 29 January 2009 (UTC)
- Maybe combine with the occasionally-seen :left and :right suffixes for finer-grained tagging when needed. --achadwick 12:48, 29 January 2009 (UTC)
- If there's a reasonable consensus that a 5-level system works, then lets tag as Cyclability=1 (easiest) to Cyclability=5 (most difficult). This translates well to the residential/tertiary/secondary/primary/trunk hierarchy, so explicit cyclability tags would only be needed for roads (or road-sections) that were notably easy or difficult. For instance, in Oxford, most of our primary roads would need adjusting to 3, with the odd section at 4 (usually a combination of <4m traffic lane, no cycle lane, and 5000+ motor vehs per day). --RichardMann 08:55, 8 February 2009 (UTC)
- We should declare up front that it's a rather objective scheme targeted at a single usage type so that we don't get into the same mess as the execrable Rejected_features/Smoothness.
- To me, too, more cyclability means that the road is easier to use. Can we go from 1 (least pleasant, "purple") to 5 (most pleasant, "yellow")? Reason being that the term should be at least a little bit intuitive to anyone who trips over one of our tags in the wild, without foreknowledge. --achadwick 18:44, 8 February 2009 (UTC)
Levels
- The five levels of suitability and the reasoning behind them are sound, I think. +1 to using this as the basis of any scheme, and it's encouraging to see that it's geared towards utility and commuter cyclists. Sports people will probably be doing their own entirely separate thing, MTB types especially; this is a good thing because we're talking about completely different skillsets. --achadwick 11:54, 11 September 2008 (UTC)
What affects this / can be used to infer it?
Add your criteria below. If OSM has a tag established or being proposed which could be used as a guide to an automated system, it'd be helpful to add a link. --achadwick 11:54, 11 September 2008 (UTC)
Factors
- Surface smoothness - (surface=* and Proposed_features/surface_values, also tracktype=*). Cobblestones are not your friend. Also Key:smoothness (ewww!), or better still Proposed_features/surface_unification.
- Lighting, for separate cycleways - lit=*.
- Abutters - those corresponding to the Cheltenham criteria (abutters=*)
- Bus routes - cleave to busy streets, and buses are awkward to move past (route=bus and Relations/Routes)
- Being inside a dry leisure=* area of pretty much any sort.
- Tram/light rail routes sharing the road - as buses, plus an unusual vehicle type and the potential for wet rails (any railway=* other than disused or abandoned, basically)
- "Traffic calming" - slightly unhelpful to cyclists because it encourages brake/accelerate/repeat behaviour in motorists, and affects the line one takes and/or bike handling. traffic_calming=*
- Choke points, pinch points and narrowings - unhelpful (narrow=*, crossing=island). The crossing sort isn't necessarily bad, depends on road layout. traffic_calming=choker
- Shared pedestrian/cycle use - unhelpful. A highway=footway|bicycle=<positive> is less convenient than a highway=cycleway|foot=<positive>. Busy highway=pedestrians which allow bikes can be inconvenient links too.
- Average and peak driver aggression (not currently tagged...)
- Time of day (think school run)
- Crossings and traffic lights above a certain threshold (instances per unit length) - nobody likes to stop/start crossing=*, highway=crossing, crossing=traffic_signals
- On-street parking. Perhaps infer this from intersections with amenity=parking areas or the rare occasions where road nodes are tagged with amenity=parking.
- Junction complexity, derived from the number of other ways converging at a single Node or sharing a junction=roundabout way.
Indicators
Some which are mere indicators of cycle-friendliness rather than direct factors towards it.
- Nearby bicycle parking capacity per unit distance, above a certain threshold (amenity=bicycle_parking). It's an indicator of cycle use in cities, which in turn correlates rather nicely with safety and how frequently drivers expect to see someone on a bike. Threshold because it doesn't really count unless it's serious.
- Presence of nearby bike rental amenity=bicycle_rental.
- Presence of nearby bike shops shop=bicycle.
The indicators above have the disadvantage that they're not part of the way itself typically, which makes potential friendliness-estimating queries more tricky.
Colours and terminology
- The Cheltenham map looks very angry-candy, and I'm not sure about how suitable the colours chosen for it would be for colour-blind people; however, OSM renderers can always choose a different scheme. The corollary of course is that any OSM tagging scheme which gets proposed that touches on the Cheltenham levels shouldn't be expressed in terms of colours! --achadwick 11:54, 11 September 2008 (UTC)
- Some people aren't going to like the term "suitability" - as all roads are surely suitable (or should be). I'm not sure what to suggest here - cyclist_skill_level_required? cycleway:pleasantness? highway:cycleability? I'm leaning towards something like {highway,cycleway,*way}:cycle_friendliness or *way:cycle_convenience currently. --achadwick 11:54, 11 September 2008 (UTC)
The approximation (existing OSM tags → Cheltenham levels)
- An interesting start. I've had a look at my commute though, and found a couple of roads which would be 1 point less suitable than the approximation would suggest (a sweeping only-just-residential road used as a rat run and which is part of a bus route, and a secondary road with horrible pedestrian islands, bad gutters, and 1½ lanes each way with right turn boxes which turn into temporary islands). Bus lanes which permit cycles might add a point of suitability, and as you've mentioned yourself a highway being in a sparsely-populated area might add more. --achadwick 11:54, 11 September 2008 (UTC)
- If a road more is or less cycle-friendly than the default for its type, should that be expressed relatively (+1, -2 etc.) or absolutely (as an override). The absolute style seems simpler to me. --achadwick 11:54, 11 September 2008 (UTC)
- I'm going to try this (key cyclability) for the city of Uppsala, Sweden. 1=best (almost no car traffic) 5=worst (no shoulders, fast traffic), according to the british standard. I need this for a few overrides, and it's at least better than inventing something completely on my own. Also IMO better using quasi-absolute values. I use grade 1=best 5=worst because it seems like the order used in Cheltenhamn, and because it's similiar to tracktype. Pereric 16:18, 6 January 2012 (UTC)
