Hi, Richard here from Traintrackr

As others have mentioned, there are more trains running than there are station LEDs, so in central London the LEDs would almost always be on, which didn't look as good.

For the MBTA in Boston we added LEDs in between each station, and even went further and added LEDs for each direction, but with only 4 lines it was much easier to put together - https://www.traintrackr.co.uk/product/mbta4

We're looking into this for London, but making it look good is significantly more complex with the number of lines and large interchange stations.

Your projects look amazing, contragulation ! You could fade the led to depict the train distance to the station ? Like that, you would have a nice transition between stations, and if there are multiples train incoming/going from it you sums the intensities ?

I think it would add another level of smoothness to it.

Consider there are over 500 trains active during (non-pandemic) peak so I guess some compromise is clearly required! And yes, a very pleasing display nonetheless.

Yes, there are typically a lot more trains active than stations, so many of the lights would be lit up nearly all the time if you tried to represent each individual train. Some lines (Victoria) actually have more trains in service than there are platforms during peak times.

It would be neat if you could say highlight a certain route or two and have a different coloured led show it transverse the line. That way it is not so cluttered with all the other trains but informative to the individual.

> perhaps lights should stay on until the train reaches the next station?

At peak times that would mean most lines would just be constantly lit

Really you need a "tunnel" LED between each station pair, so you could extinguish the one light, light the "in transit" light. I guess it would need 2 or more LEDs per inter-station section (or a colour change).

I don't think London Underground release that level of information. Thameslink does[1], Overground should too.

https://www.opentraintimes.com/maps/signalling/tlk_core

I expect TfL's "Tube departure boards, line status and station status"[0] feed would suffice. It's updated every 30 seconds. Plenty more data available too.

[0]: https://tfl.gov.uk/info-for/open-data-users/

This! A "tunnel" LED between stations should be only 25% bright and with distinct color.

UPDATE: Maybe a LED per direction in tunnel would also be useful.

At that point you're better off just getting a screen and drawing whatever you want on it, and kind of losing the point of the project, frankly.

Yes, I guess we're information junkies! The feature-creep is real.

I seem to recall the actual control centres used to use a big map with the train lines drawn using a line of bulbs, and indicating trains buy a series of bulbs. Similar to this, http://photos.signalling.org/_datas/o/n/d/ondcx12zxd/i/uploa... .

PC motherboard OEMs have done some interesting things with RGB LEDs and areas of the PCB with clear or no soldermask and copper removed from all layers to leave a translucent region of fiberglass that can be back-lit. This can achieve an effect similar to electroluminescent wire, and would be suitable for the tunnel segments of the map.

Each tunnel is only for a single direction and thus you can actually have multiple trains between the same two stations but heading in opposite directions. Moreover, at rush hour some of the busier lines might even have more than one train in the same tunnel for some stretches of tracks.

There is no way a PCB this size could give an accurate representation. I'm not even sure that level of detail is even published by the TFL. But it shouldn't matter, this is clearly intended to be more ornamental than it is a functional tool for locating carriages.

If you can show a train leaving, and a train arriving then you only lack direction, which should be in the datastreams.

So you'd leave(station=A,direction=0), then increment the tunnel A-B until you next had an arrive(station=B,0) when you'd decrement the tunnel section. Even branched tunnels Should Just Work ®. The tunnels are stacks, unless there are hidden sidings and such, things should add up. Bonus you change colour according to magnitude of $tunnelABC.

You'd need just under twice the LEDs though.

More than twice because each station has multiple platforms so you'd need more double the LEDs just for the stations (stations with more than one line would need a minimum of 4 times as many LEDs). Then you have to double that up for each tunnel too. Even with your revisions if you have a train arriving on one platform and leaving on another, which does actually happen (a lot!), then the PCB has no way of representing that data stream.

Ultimately the level of detail you're describing is not feasible with the aesthetic the designer was going for. This is one of those problems that appears much easier than it really is.

Plus, at risk of repeating myself, this is clearly intended to be more ornamental than it is a functional tool for locating carriages.

>Ultimately the level of detail you're describing is not feasible with the aesthetic the designer was going for. //

Absolutely. Appreciate your comments ... maybe when the kids leave home I'll get around to putting my money where my mouth is.

Hi, Richard here from Traintrackr

For the MBTA in Boston we did this, but their system is much less complex than London - https://www.traintrackr.co.uk/product/mbta4

>Although it’s designed to work with TrainTrackr’s own servers, you can reprogramme the chip if you want, and they provide some details for people who can do that sort of thing.

Should be simple enough if you're up to it - prove you are worthy to display something like this :)

Maybe let it blink fast while the train is moving towards the station? Or the other way around if you prefer a more calm overall appearance of the board.

Experiment with blinking the leds synchronously (or not).

It might be nice to be able to see train delays and flow.

Circuit-board transit maps face the challenge of showing train flow with their few LEDs. Online transit maps have lots of pixels, but face the challenge of showing patterns of flow at time scales larger than a users glance.

One brainstormy idea that has come up in conversation, is to do something analogous to wind graphics like [1], which convey air motion using sample particles moving with unrealistic speed. Perhaps one might do something similar with trains?

[1] https://www.windy.com/-Pressure-pressure https://www.windfinder.com/

Your updated suggestion was my first thought as well. That way you could follow a train as it moves from one station to the next.