Google’s driverless cars can’t spot potholes or drive in heavy rain

Guess we’re not going anywhere today, then. Image: public domain.

And it seemed like everything was going so well for Google’s amazing new driverless cars. The first set of prototypes has been tested; they’ve driven over 700,000 miles of US roads; they’ve even created a second generation two-seater car with what looks like a friendly face on the front:

Aww, look at its smiley face.

So you could be forgiven for thinking that Google were on the home straight, and we’d all be chauffeured around in autonomous vehicles before the year was out.

But, it turns out, not so much. The most recent issue of MIT Technology Review has revealed a list of the things the cars can’t yet do, as confirmed by Chris Urmson, director of the Google car team. These range from the mildly problematic  - for example, the cars can’t detect the nature of an obstacle, so would swerve around balls of paper as though they were rocks... the downright concerning. Such as not having been tested in adverse weather conditions such as snow or rain. Or being able to detect open manhole covers or potholes.

Perhaps the most worrying issue, however, is the fact that they still can’t operate on most roads. The cars rely on painstakingly detailed 3D maps, which require multiple visits to streets and analysis by both humans and computers: simply downloading Google Maps won’t cut it. And, since the cars can’t respond to unexpected visual signals, like temporary route changes or new sets of traffic lights, these maps must also be updated constantly. That’s a lot of effort, and so comes at a cost.

Urmson assured the publication, however, that engineers are hard at work on all these issues, and he still hopes the cars will be on roads within the next five years, by the time his 11-year-old son turns 16: “It’s my personal deadline.”

Like what you see? Why not follow CityMetric on Facebook or Twitter. Go on, we're lovely.


In which British cities is renting the norm?

Oh, good. Image: Getty.

The latest instalment of our weekly series, in which we use the Centre for Cities’ data tools to crunch some of the numbers on Britain’s cities. This week we're getting a bit wonkish.

We write about rents a lot around here – a hell of a lot, considering the place home ownership occupies in the British psyche. At least part of the explanation for that is that we're based in London, where most people under 30 – and a growing number over it – are living in the private rental sector PRS, with no hope of escape.

But London, as so often, is unusual. London households, in fact, are nearly twice as likely to rent as those in some other cities – including big ones, like Glasgow.

Below is a chart showing the percentage of households that are neither owner occupied, nor in social housing, in 62 British cities at the time of the 2011 census. These figures will include a few households living rent free (lucky them) – but the vast majority will be renting privately. We've colour coded it by region, in the hunt for patterns.

These figures are five years old, of course – given broader trends in the housing market, renting has likely become more common in many, if not most, of these cities. But that caveat aside, here are the figures.

Click to expand.

In 2011, at least, roughly a quarter of London households were in the PRS – but in a few cities it was even more common.

Unusually for these stories, the regional pattern is relatively limited. Renting seems to be more common in northern cities than southern ones – but the difference is pretty slight. Size doesn’t seem to be that big a factor, either: both ends of the chart include both large and small cities.

So what explains the pattern? Oxford and Cambridge both have disproportionately high student – and so, temporary – populations, which probably warps the figures. But the big thing, I fear, is prices.

Here's the same figures, plotted against the "affordability ratio" (average house prices as a multiple of income). It's interactive, so you can get the data on each city.

That is a correlation coefficient of 0.61 – which is pretty strong. And the fact that the most expensive cities also have the most expensive housing is probably not a coincidence. In other words, there's a fairly good chance that the reason more people rent in London – and Oxford, and Cambridge, and Brighton – is because they can't afford to buy.

And this, remember, was 2011. Do you really think it's got better since?

Want more of this stuff? Follow CityMetric on Twitter or Facebook.