OpenStreetMap logo OpenStreetMap

Changeset When Comment
29739088 over 10 years ago

OK, Caltrain publishes web pages and printed schedules that say Gilroy is a station on the Baby Bullet line.

If you would like one, here it is: http://www.caltrain.com/schedules/weekdaytimetable.html

If you would like me to endeavor to be quite exact with web links and exact publication names in source tags (well, changeset source comments, not source=* tags -- although I endeavor to put web links in source=* tags, and have for years), I can do so. However, a messy URL doesn't easily paste into my JOSM upload dialog, so instead I type in what is a reasonable expectation.

If "Caltrain" doesn't make sense to you as the name of a public train route sufficient for you to say "Oh, Steve simply completed the last station in the route by consulting the operators of the route itself -- he must have consulted one of their schedules or a web site containing one..." then I guess we have different senses of what it means to come to a logical conclusion.

I will endeavor to be more exact in my sources in future, though I believe I've been pretty good about them (Personal knowledge, Bing imagery, a specific book, a survey I made myself, a GPS/GPX track...) for most of the life of OSM.

If replying to you via email doesn't make sense for this sort of "changeset comments" (i.e. you think I should be typing this into the changeset comment "process"), please let me know that and I'll cut-and-paste.

Regards,
Steve

29723896 over 10 years ago

Hello Serge:

The "infrastructure on rail" tag of "highspeed=yes" is documented as widely used on the OpenRailwayMap (ORM) wiki here: osm.wiki/OpenRailwayMap/Tagging#Tracks It says "Is this line a high-speed line (with permissible speeds greater than 200 kph)?" The boolean allowed values are yes or no. 200 kph translates to about 122 mph.

Amtrak says that the Acela Express line offers "Superior Comfort, Upscale Amenities, Polished Professional Service, at Speeds up to 150 mph" here: http://www.amtrak.com/acela-express-train . Clearly, 150 > 122. Also, at http://www.amtrak.com/train-schedules-timetables Amtrak lists its first route as "Acela Express - see Northeast Corridor timetables." So, taken together, Amtrak provides us with these data.

Please note that it is the Acela Express LINE (route=train) which offers these speeds, so effectively the entire infrastructure (route=railway) meets the "yes" definition for ORM's highspeed tag. ("Is this LINE...high-speed...with PERMISSIBLE speeds..."). To me, this means that this tag can and should be applied to the underlying rail infrastructure.

Again, this infrastructure is the Northeast Corridor, whose tracks ALLOW trains at speeds > 122 mph. That is why the tag is correct. Please note (by ORM wiki section) that the highspeed=yes tag does not go on route=train relations (or elements) but rather track/infrastructure elements. I believe I have done this correctly by asserting the tag on all track elements which make up the Northeast Corridor route=railway relation: the entire "subdivision" (route=railway) supports highspeed trains, so highspeed=yes on its elements is correct.

ORM's default display is the "Infrastructure" radio button, but there are also its "Maxspeed" and "Signalling" map styles. If exhaustive tagging were correctly applied to each track element of the Northeast Corridor (including maxspeed=245, correctly in kph, about 150 mph), the train would rocket through curves and small towns in ways it actually doesn't. (As you personally experienced). And as it is early days in USA rail tagging (and VERY early tagging in USA speedlimit rail tagging), we haven't applied this exhaustive tagging. But it would be correct to ALSO apply to each and every track segment where it is known (and on-the-ground verifiable, often with a speed limit sign that can be seen by train passengers) a speedlimit= tag.

Correctly completed, this would accurately result in ORM displaying (with Infrastructure style) a solid red line on Northeast Corridor, properly reflecting highspeed=yes tags. It would also accurately result in ORM's Maxspeeds style displaying a "rainbow" of colors representing different speeds: some straight and no station segments would have speedlimit=245, others (near stations, around curves) will be lower. Try this, but not in the USA (there are just a few spots of color representing Maxspeeds displayed on ORM in USA -- early knowledge and a tiny start of data entry by novice rail folks still finding our legs on how to do this). I think a Maxspeeds view of a high-speed rail line in Germany or China will give you a better sense (through color representing speedlimit) what you experienced while riding the Acela Express. But the whole line being red in Infrastructure view because the entire infrastructure supports highspeed=yes? Yup, that's how it's done.

Relax, Serge. This is the only line in North America where the highspeed=yes tag is appropriate. I nor anybody else are going to assert it anywhere else, unless more highspeed trains are built. Please do use ORM's Infrastructure view (and documentation) to see (and understand) that this is the correct way to do it for highspeed trains in Europe and Asia. We have exactly one highspeed train in the USA -- Acela Express -- and I believe now is as good a time as any that we allow ORM to properly display this by tagging it as such.

Rail in the USA has a long, long way to go. But if we correctly tag each and every brick in the wall one by one by one, eventually, we'll really have something. THAT is an important essence of OSM. I hope you feel the same way about it as I do, as Rome wasn't built in a day.

Thanks for your comments, and I welcome continued discussion on the topic if you wish,
Steve

27586920 about 11 years ago

I have "knowledge" of these segments of freeway, also. They are not highway=trunk, they are highway=motorway (fully controlled-access "freeway" in California). They are even all named "Freeway." Please consider changing back to highway=motorway.