Won't work in subway. No coverage.
MTA Releases Subway Time App
11–20 of 43 posts
Re: MTA Releases Subway Time App
#12Why.. why.. is that app pitch black? Thats not the Android style, thats lazy.
A lot of subway apps are black. I assume it's because most of subway signage is black. Here's a black app that's well designed: http://letsembark.com.
Re: MTA Releases Subway Time App
#13> “This is what generations of dreamers and futurists have waited for,” said MTA Chairman and CEO Joseph J. Lhota. “The ability to get subway arrival time at street level is here. The breathlessness of the coverage of this app makes me wonder how much money was spent on it? First of all, the main problem for New Yorkers is the lack of this data for all the other train lines (i.e A-Z). Second, the MTA has, to their cr…
> " First of all, the main problem for New Yorkers is the lack of this data for all the other train lines (i.e A-Z)." Unfortunately this is not going to be fixed any time soon. BMT/IND trains have a distributed command and control system. Multiple signal towers control train movement within their own sectors of the system - and each signal tower has no information about the rest of the system. This was necessary in t…
Let's assume that there's a byzantine system in which two parallel and unconnected systems control both BMT/IND trains...at some point, each train communicates arrival and destination data to its respective system. Why can't both systems report to a single controller? At some point, this information is centralized (dear God I hope it is, especially for evaluating performance metrics)...I can't see how it would be hard to provide this digitized data format at real time.
Re: MTA Releases Subway Time App
#14Earlier quoted context omitted.
> " First of all, the main problem for New Yorkers is the lack of this data for all the other train lines (i.e A-Z)." Unfortunately this is not going to be fixed any time soon. BMT/IND trains have a distributed command and control system. Multiple signal towers control train movement within their own sectors of the system - and each signal tower has no information about the rest of the system. This was necessary in t…
What legacy system could possibly prevent one from simply recording the position of every train every few seconds? This is not a particularly difficult problem for a billion-dollar business to solve.
One built in 1904.
The control systems of the MTA are purely electromechanical. It goes way beyond what one would normally call a "legacy system".
You can't record the position of trains because there is no way to snapshot the whole system. Only the signal tower local to that section of the system is aware of what's going on in its zone. This is a vestige of the design where there was no reasonable way to centralize that amount of signaling over such great distances.
To get a snapshot of the whole system you'd have to simultaneously snapshot the state of every signal tower in the system and find some way to collect this information centrally. This sounds reasonable until you realize that the control system, being 50 years pre-computer, is unaware of individual trains. It doesn't detect trains, only presence of at least one car on a section of track (detected by the third rail making contact with the train).
To ascertain which train is where you'd have to either have dispatchers identify the train by communicating with operators (hard to poll), or infer the identity of a train by monitoring state. Both are quite difficult when all of your data is spread all over the entirety of NYC in isolated distributed control centers.
The IRT trains spent billions centralizing all command and control into a single building in Manhattan, and thus snapshotting state is trivially easy. The BMT/IND segments of the system are substantially bigger, with more stations, than even that. A full modernization to electronic control is necessary, which will cost many billions.
Re: MTA Releases Subway Time App
#15Except that there's never any reception in subway stops, no?
Re: MTA Releases Subway Time App
#16Earlier quoted context omitted.
What legacy system could possibly prevent one from simply recording the position of every train every few seconds? This is not a particularly difficult problem for a billion-dollar business to solve.
One built in 1904. The control systems of the MTA are purely electromechanical. It goes way beyond what one would normally call a "legacy system". You can't record the position of trains because there is no way to snapshot the whole system. Only the signal tower local to that section of the system is aware of what's going on in its zone. This is a vestige of the design where there was no reasonable way to centralize…
So on the decentralized systems, how does one station know when to delay a currently-stopped train because there's a delayed train farther up the route? Do signal towers up ahead simply transmit to adjacent stations "Delayed train up ahead?"
Re: MTA Releases Subway Time App
#17Except that there's never any reception in subway stops, no?
So for the trains on which they have real-time data, there are already LED-boards that show arrival time:
If you're on the platform, you'll be able to see the time even if your phone isn't working. So the mobile app will be useful if you're en route to the station and need to know how many minutes you have left.
Re: MTA Releases Subway Time App
#18Earlier quoted context omitted.
One built in 1904. The control systems of the MTA are purely electromechanical. It goes way beyond what one would normally call a "legacy system". You can't record the position of trains because there is no way to snapshot the whole system. Only the signal tower local to that section of the system is aware of what's going on in its zone. This is a vestige of the design where there was no reasonable way to centralize…
So on the decentralized systems, how does one station know when to delay a currently-stopped train because there's a delayed train farther up the route? Do signal towers up ahead simply transmit to adjacent stations "Delayed train up ahead?"
Pretty much. A signal tower usually controls several stations, so delays up ahead are usually contained within the zone of control of a signal tower.
In cases where delays are more substantial and you need to hold trains further upstream, this is communicated manually between towers.
Much of the control here is not based on semantic data, but rather verbal. The actual control system itself isn't capable of much more than indicating which piece of track is occupied.
Re: MTA Releases Subway Time App
#19Earlier quoted context omitted.
What legacy system could possibly prevent one from simply recording the position of every train every few seconds? This is not a particularly difficult problem for a billion-dollar business to solve.
One built in 1904. The control systems of the MTA are purely electromechanical. It goes way beyond what one would normally call a "legacy system". You can't record the position of trains because there is no way to snapshot the whole system. Only the signal tower local to that section of the system is aware of what's going on in its zone. This is a vestige of the design where there was no reasonable way to centralize…
I thought the presence of the train on given section of track was actually detected by the trains wheels completing the circuit between the rails, not with the third rail.
Re: MTA Releases Subway Time App
#20This app also has a web version: http://apps.mta.info/traintime/ Which means the MTA has unintentionally developed an API: http://advisory.mtanyct.info/Test/gtfs/scraper.php?line=1...
I doubt it was unintentional. I know some guys at MTA who work on this stuff, and they are all about open data and APIs and robots etc.