One of the most fun things to do, for those who enjoy claustrophobia and other people’s body odour, is to attempt to use a mass transit system at rush hour.
Travelling on the Central line at 6pm, for example, gives you all sorts of exciting opportunities to share a single square inch of floor space with a fellow passenger, all the while becoming intimately familiar with any personal hygiene problems they may happen to have. On some, particularly lovely days you might find you don’t even get to do this for ages, but first have to spend some exciting time enjoying it as a spectator sport, before actually being able to pack yourself into one unoccupied cranny of a train.
But fear not! Transport for London has come up with a plan: telling passengers which bits of the train have the most space on them.
— Transport for London (@TfL) October 17, 2017
Here’s the science part. Many trains include automatic train weighing systems, which do exactly what the name suggests: monitoring the downward force on any individual wheel axis in real time. The data thus gathered is used mostly to optimise the braking.
But it also serves as a good proxy for how crowded a particular carriage is. All TfL are doing here is translating that into real time information visible to passengers. It’s using the standard, traffic light colour system: green means go, yellow means “hmm, maybe not”, red means “oh dear god, no, no, no”.
All this will, hopefully, encourage some to move down the platform to where the train is less crowded, spreading the load and reducing the number of passengers who find themselves becoming overly familiar with a total stranger’s armpit.
The system is not unique, even in London: trains on the Thameslink route, a heavy-rail line which runs north/south across town (past CityMetric towers!) has a similar system visible to passengers on board. And so far it’s only a trial, at a single station, Shoreditch High Street.
But you can, if you’re so minded, watch the information update every few seconds or so here.
Can’t see why you would, but I can’t see why I would either, and that hasn’t stopped me spending much of the day watching it, so, knock yourselves out.
UPDATE: A letter from reader Randy Alfred in San Francisco:
You forgot to mention that it's not only about the personal comfort of passengers.
It takes longer to wedge into a crowded carriage, so diverting passengers to less-crowded carriages reduces the dwell time that the train spends stopped in a station. That reduces travel time for passengers and increases the otherwise-limited capacity of the rail line, allowing (if the rolling stock is available) more frequent as well as faster service. That's two additional advantages over the one you cite.
Good point, well made.