Driverless cars still need a firm hand on the wheel
In 2012, Sergey Brin made a bold prediction. Within five years, Google's co-founder claimed, members of the public would be able to ride in cars that drive themselves.
Not everybody took Brin seriously at the time, and not only because he was going through a phase of wearing the peculiar Google Glass headset at every public appearance. Google had been testing driverless cars for just three years, and few knew how much progress the company was making.
However, it turns out that Brin's prediction was off by only a year. Last week, Waymo, a subsidiary of the search company's Alphabet parent that was spun off from Google two years ago, launched a commercial driverless taxi service to the public.
In an area of Phoenix, Arizona, people can now open an app on their smartphone, select a destination and, within a few minutes, have a driverless car arrive to take them there. The future, it seems, has arrived.
Well, not quite. Several important caveats apply. Only a select group of riders - 400 individuals - are able to take part. The service applies to just a small part of the city at first. And the driverless cars will still have a safety driver, to take control should the software driving the car put its passengers in danger.
The last point is the most glaring, because Waymo had claimed that by this point, human supervisors - a safety measure that has been in place since it first began tests almost a decade ago - would no longer be needed.
But like an anxious parent who resists removing the stabilisers from their child's bicycle, not yet confident enough that they can ride safely without them, Google is reluctant to do without its safety drivers. It is not the most encouraging sign.
This, by the way, is all in an area that Waymo has been conducting tests for 18 months and has mapped in painstaking detail - currently a requirement for driverless cars. It will take many years to map enough of the world in such detail to remove human driving from the equation.
The strings attached to Waymo's big moment show that, however much progress driverless car technology has made, it is still a long way from the point at which an unsupervised vehicle can take a passenger.
In the past year or so, most experts in the field have pushed back their expectations for the day of "level 5" automation, the term for a fully independent driverless vehicle.
Suddenly, Brin's prediction is not looking so good. Driverless-car optimists point out that the technology has come a long way. The number of "disengagements" - the occasions on which an emergency safety driver must take control of a car - has fallen in recent years. In California, Waymo reported 63 disengagements over 352,444 miles (567,203km) of testing - a rate of 0.18 every 1,000 miles. Two years earlier, it recorded 0.8 disengagements per thousand miles.
That is undoubted technical progress. But it does not tell us the point at which driverless cars are "ready". The consensus is that even as autonomous technology gets better by the month, the point it must reach seems to be getting further away at an equal rate.
Waymo, by the way, is seen as the leader in driverless technology. Others are faring worse. Uber suspended its driverless car programme in March when one of its vehicles hit and killed a pedestrian. The company is planning to resume tests. The ride-hailing app once sold investors on the idea that it would become wildly profitable by removing its biggest expense - drivers - from its cars, but no longer makes such claims, even as it prepares to go public next year. Tesla, too, has cut back its predictions. It recently stopped offering buyers the option for their car to become "fully self-driving" through a future software update, apparently because such a feature is not as close as hoped.
This is not to say driverless cars are never going to happen. In the meantime, semi-autonomous features, such as cars that park themselves and drive unassisted on highways, will become increasingly ubiquitous.
But the day when most of us can order a robot taxi is undeniably further away than was hoped for until recently.
- © The Daily Telegraph, London