The idea that you can wait ages for a bus, and then two will come along at once, is a cliché. It’s also, as it turns out, mathematically inevitable.

It works like this. Buses can start off evenly spaced, but inevitably, at some point, one will be delayed (a little old lady takes a minute finding her change, say). The slight delay means that, at the next stop it reaches, there will be more passengers waiting; they will take longer to board or disembark, so the bus stops for longer.

Delays begat delays, the bus gets further and further off schedule, and eventually the bus behind – which is now sweeping past empty stops that were cleared of passengers mere moments ago – catches it.

And so, at some point, two buses arrive at once. And, in all likelihood, one will be surprisingly empty.

There’s even a name for this phenomenon: bus bunching.

This is pretty irritating, on the whole – and so it’s one of the problems that the transport app firm CityMapper is trying to solve with its foray into “smart buses”. On board one of the three green minibuses serving the popup route CMX1, business development director Damien Bown tells passengers that the firm is trying to use a combination of real-time passenger loading data, and regular communication between driver and control room, to keep the buses evenly spaced.

Not everyone on board seems convinced by this: the popup bus serves a loop taking in Waterloo and the Strand, yet the app shows two of the three buses lurking around Blackfriars.

But Bown blames the traffic on the South Bank: at present it takes so much longer to do the south eastern corner of the route that ensuring there’s a bus every 10 minutes means that, in some some places, they’re going to look like they’re bunching. “Spatially they are,” he tells us. “Temporally they’re not.”

Except a few moments later this happens:

Which rather ruins that theory.

Still. We’re all here to learn.

****

CMX1 isn’t like the other buses. For one thing it’s bright green, in CityMapper’s corporate colours. For another it’s smaller – just a minibus. It’s also, at least, relatively, green in another sense: not electric, but it does at least meet low emissions standards. On board, you can use USB chargers to charge your phone, if you feel the need.

It’s also high-tech, too, as buses go. There’s an electronic information board, which flicks between maps and lists of upcoming stops with estimated arrival times and information on the bus itself (our driver today is Piotr). And obviously, it appears in the CityMapper app, where it’s also being promoted. So far, alas, you can only request the bus stop the old fashioned way.

As well as the driver, each CMX1 is manned by two CityMapper staff, who discuss the project with passengers, hand out CityMapper badges and generally seem to be having a good time. The service is running all day Tuesday and Wednesday, ferrying passengers clockwise around a loop that takes in Blackfriars Bridge, Fleet Street, Waterloo Bridge and the South Bank.

The new bus has, if not the active involvement of Transport for London (TfL), then at least its passive support. The route isn’t charging fares, in part so as to avoid difficult questions about licensing; but the transport authority is nonetheless allowing the buses to use its stops, and the occasional presence of TfL staff on the bus suggest that they’re as keen to find out what CityMapper has learned as the firm itself is.

And the tech firm seems very excited, to the point of having given the scheme a codename, Project Grasshopper. (Yes, really; originally it was Project Caterpillar.) In a Medium post, it promised “a smarter bus service”, adding:

“…you’re going to see us ‘rethink’ how buses and routes operate and how to make them more efficient and useful in cities.”

Which sounds very grand on the whole.

The tech firm’s theory is that, in the current transport system, there’s a gap between full-sized buses and personalised vehicles like cabs. As things stand there’s no mode of transport that can plug this gap: it’s either an expensive Uber, or a half-empty bus. (I’m not convinced this is the best example, but Damien points to late-night short hops from major stations like Clapham Junction, currently provided by cabs.)

There are other problems with official bus services, too. They’re inflexible, serving the same route, rather than simply finding the fastest possible route between the same stops. What’s more, city transport authorities are not always able to provide every route for which there’s demand.

And CityMapper is sitting on a mountain of data showing how people are actually using transport networks, so thinks it’s well-placed to work out where those routes are. To quote that Medium post again:

“We built an ultimate tool (codenamed: Simcity) to evaluate routes utilising our demand data and routing. We found we can figure out how to improve existing routes in all of our cities. We can also identify new and better routes. London is actually not that badly served, but other cities have major gaps.”

Making things work on a computer simulation is one thing; doing so in an actual, living city with congestion and so on is quite another. Hence, CMX1, to find out exactly what might be more challenging than it looks.

****

When the buses start to bunch, everyone on the second one is turfed off and joins us on the first, to even out the gaps in the service.

This, though, is fine: very few of us on the bus are actually going anywhere. At Blackfriars station, a man in a suit and his small son get on, heading for Somerset House; but even they have chosen this route over others for the novelty factor, and for the most part, we’re just along for the ride, to enjoy the novelty of a pop-up bus route. There’s a guy from Just Eat; a couple of people from advertising or tech firms; and a few enthusiastic transport nerds asking about the technical side of things. I doubt I’m the only one here planning to turn my ride into #content, either.

There are even a few people from TfL’s bus performance division, to see how it’s all going, and possibly enjoy a moment of schadenfreude in watching a tech firm learn that running buses is harder than it looks.

The guys from CityMapper seem pretty cool with that: for them, it’s a learning experience. As well as working out how to prevent bunching, they’re finding out how optimise the amount of contact between driver and HQ, so they can make the most of the data without distracting anyone from driving. They’ve discovered that their glitzy information system is not positioned quite well enough to be visible from everywhere in the bus. They’ve deliberately experimented with how easy it is for a small carer to get a large wheelchair onto the bus.

Oh, and they’ve also discovered that often the door won’t close without Damien giving it a shove.

CMX1 in action, sort of. Image: author provided.

One of the jokes people tend to make about venture capitalists is that, with shared car services like UberPool, Silicon Valley is very slowly re-inventing the bus. In some ways, then, it’s reassuring to see a tech firm like CityMapper lean into this, and actually try to improve bus services instead. After all, buses do have certain advantages, in terms of being an efficient use of space in environments that are short of it. If there is a way of using more of them to get cars off the road then, well, that’s got to be a good thing.

CMX1 ran all day yesterday, and is running all day today, too. Then, it will vanish for a couple of weeks while they think again. At some point, CityMapper will back with a new popup bus route which will, hopefully, work better. Then they’ll stop again, and try again, and so on.

Until, one day, perhaps they’ll be ready to make it – or something like it – a proper bus.

Whether it’ll work remains to be seen. But it’s kind of cool that a firm which made its name in mapping and journey planning is actually bothering to find out.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and also has a Facebook page now for some reason. 

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