Driverless automobiles - The car that parks itself
[1] CARS that need no driver are just around the
corner according to researchers who have been
testing vehicles bristling with aerials and cameras
on public roads in America. However, researchers
[5] do not make cars, so it will be up to firms that do
to bring the technology to market. And carmakers
are a conservative bunch. Still, slowly and steadily
the autonomous car will arrive, with the help of an
increasing number of automated driving aids. A
[10] Swedish carmaker has recently demonstrated one
such feature: a car that really does park itself.
Some cars already have systems that assist with
parking, but these are not completely autonomous.
They can identify an empty parallel-parking space
[15] and steer into it while the driver uses the brake. The
Swedish system, however, lets the driver get out and
use a smartphone application to instruct the vehicle
to park. The car then trundles off, manoeuvres into
a parking place and sends a message to the driver
[20] to inform him where it is. The driver can collect the
car in person or use his phone to call it back to where
he dropped it off. Autonomous parking could thus be
provided at places like shopping centres and airports,
which are controlled areas in which automated
[25] vehicles can be managed more easily than on open
highways.
In the past, designs for doing this have relied
on car parks being fitted with buried guide wires
that a vehicle can follow to an empty bay. That,
[30] though, creates a chicken-and-egg problem: car-park
operators will not invest in such infrastructure until
there is a sufficient number of suitably equipped cars
on the road. Drivers, conversely, will not want to buy
self-parking cars if there is nowhere to use them.
[35] This means, as a safety engineer working on
the project observes, that for autonomous parking
to work most of the technology will have to be in the
car itself. The test car, which looks like a normal car,
therefore uses on-board GPS mapping, cameras with
[40] image-recognition software, and radar sensors to find
its own way around a car park and avoid pedestrians
and non-autonomous vehicles. The same engineer
says the system is five to ten years from commercial
deployment. If it proves a success then infrastructure
[45] might adapt to it, for instance by packing cars into
tighter spaces. If there is no one in them there is no
need to make room for their doors to open.
Driverless cars would also need to communicate
with one another, to enhance safety. That, too, is
[50] coming. A number of carmakers are developing
wireless networking systems through which vehicles
can exchange data, such as their speed, their steering
∠ and even their weight, to forewarn anti-collision
systems and safety devices if an accident looks likely
[55] In the USA, for example, a carmaker recently
tested a brake light that can provide an early warning
to other motorists. If the brakes are applied hard in an
emergency, a signal is broadcast. This illuminates a
warning light in the dashboard of suitably equipped
[60] following vehicles, even if they are out of sight around
a bend or not immediately behind the vehicle doing
the braking.
The American company has been testing this
system as part of a collaborative research project
[65] with several European carmakers. They have put a
fleet of 150 experimental vehicles on the roads. When
they tested a group of these, the Americans found
the technology let drivers brake much earlier, helping
avoid collisions. A driverless car would be able to
[70] react even faster.
Another member of the research group has been
testing driverless cars on roads around Munich—
including belting down some of Germany’s highspeed
autobahns. The ordinary-looking models use
[75] a variety of self-contained guidance systems. These
include cameras mounted on the upper windscreen,
which can identify road markings, signs and various
obstacles likely to be encountered on roads.
The German cars also use a radar, to gauge
[80] how far the vehicle is from other cars and potential
obstacles, and a lidar, which works like a radar but
at optical frequencies. The lidar employs laser beams
to scan the road ahead and builds up from the
reflections a three-dimensional image of what this
[85] looks like. The image is processed by a computer in
the vehicle, which also collects and compares data
from a high-accuracy GPS unit. A series of ultrasonic
sonars similar to those used in vehicles to provide
parking assistance are placed around the car to add
[90] to the virtual picture. And just to make sure, a set of
accelerometers provide an inertial navigation system
that double-checks the vehicle’s position on the road.
Although these cars can be switched to an
autonomous driving mode, they are still required to
[95] have someone in the driving seat who can take over
in the event of any difficulty. Some cars can steer
themselves, slow down, brake and accelerate, even
changing lanes to overtake slower vehicles.
From the print edition: Science and Technology Jun 29th 2013
In “They have put a fleet of 150 experimental vehicles on the roads” (. 65-66), “a fleet” could be replaced by
