It looks like a blue dragonfly. Then its miniature wings begin to flap as it
slips under the door and darts along the street. After rising through the
air it stops to hover outside the window of a building several storeys high.
There is an opening on the roof, and it slips inside. As it flits from room
to room its video-camera “eye” transmits pictures to a screen on a
remote-control unit strapped to the wrist of its clandestine operator.
This is not a scene from a James Bond film, in which 007 tests a new device
from “Q”, but an animated video produced by Onera, France's national
aerospace centre, to explain REMANTA, a project to develop the technologies
needed for miniature robotic aircraft. More bug-like flying devices are
being developed in other research laboratories around the world. A few are
already small enough to be carried in a briefcase; others are the size of a
jet fighter and need a runway for take-off.
Having evolved from military use, drones, or unmanned aerial vehicles
(UAVs), are taking to the air in increasing numbers for public-service and
civilian roles. They are being operated by groups as diverse as police,
surveyors and archaeologists. A UAV helped firemen track the blaze that
recently ravaged southern California. The most immediate advantage of a UAV
is cost: operating even a small helicopter can cost $1,000 an hour or more,
but the bill for a drone is a fraction of that. However, the growing use of
UAVs is causing a number of concerns.
The first is safety. Last month America's National Transportation Safety
Board (NTSB) completed its first-ever investigation into an
unmanned-aircraft accident. Pilot error was blamed for the crash in Arizona
in April 2006 of a 4,500kg (10,000lb) Predator B, a type of UAV used by
American forces in Iraq and Afghanistan. It was being operated by Customs
and Border Protection when its engine was accidentally turned off by the
team piloting it from a control room at an army base. No one was hurt, but
the NTSB issued 22 recommendations to address what Mark Rosenker, its
chairman, described as “a wide range of safety issues involving the civilian
use of unmanned aircraft.”
The second concern is privacy. UAVs can peek much more easily and cheaply
than satellites and fixed cameras can. Although it is possible to peer into
someone's back garden with Google Earth, the images are not “live”—some are
years old. Live satellite images can be impaired by clouds and darkness. A
UAV, however, is more flexible. It can get closer to its target, move to new
locations faster and hover almost silently above a property or outside a
window. And the tiny ones that are coming will be able to fly inside
buildings. Before long paparazzi will put cameras in them to snatch pictures
of celebrities.
Unmanned aircraft have been around almost as long as powered flight. In the
first world war they were used as flying bombs and by the second as
radio-controlled targets and for reconnaissance missions. In Afghanistan and
Iraq they have also been fitted with missiles.
In more recent years the development of unmanned aircraft has become a
process of technological democratisation. Lightweight construction
materials, engines, microelectronics, signal-processing equipment and
navigation by global-positioning satellites (GPS), are all getting more
sophisticated, smaller and cheaper. As a result, so have UAVs.
Flown from afar
A Predator, including ground equipment, costs around $8m. It is capable of
operating in harsh conditions for more than a day. Even though a Predator
may be flying over a remote part of Iraq, it is more than likely being
controlled by pilots working in shifts and sitting in front of a video
screen thousands of miles away at an air force base in America. Smaller,
lighter and simpler UAV reconnaissance systems are being developed for
troops in the field. These can be hand-launched, which reduces the need for
remote-control piloting skills. Landings can be as simple as cutting the
engine once the UAV has returned from its pre-programmed mission, at which
point it flutters down to earth on a parachute.
Some hovering types can land automatically. One such device is made by
Microdrones, a German company. Their flying machine looks like a small
flying saucer with four rotor blades on stubby arms. It is not much bigger
than the laptop computer used to program its flight and monitor what it is
looking at. It can stooge around for about 20 minutes carrying video and
infra-red cameras. Some police forces have started to try it out. Earlier
this year British bobbies used one to keep an eye on a music festival,
busting people for drug offences and catching others breaking into cars.
The Los Angeles County Sheriff's Department, which operates more than a
dozen helicopters, has experimented with a foldaway UAV. It has wings and an
electric engine, and can be assembled in minutes for hand-launching. It has
a flight time of around 70 minutes. At around $30,000 all in, it is a lot
cheaper than another new helicopter at around $3m.
Scientists are using UAVs to help with experiments. The Scripps Institute of
Oceanography in San Diego flew a fleet of them in stacked formation over the
Maldives in the Indian Ocean last year. They were collecting air samples
simultaneously from different altitudes for research into the effects of
global warming.
In time, UAVs are likely to be employed for all sorts of jobs for which the
use of an aircraft big enough to carry a pilot would be too dangerous,
impractical or too expensive. Surveyors, for instance, could use a hovering
UAV to inspect the walls of a tall building in a crowded city. A television
station could use one to show traffic conditions. And as with all new
technologies, unmanned vehicles will have uses that have not yet been
imagined.
Already, the technology is so easily available that you can build a basic
UAV for around $1,000 from model-aircraft parts, the innards of a GPS unit
and a Lego Mindstorms robotics kit—just as Chris Anderson has done. Mr
Anderson, the editor of WIRED magazine, has set up a website for other
DIY-makers of low-cost UAVs.
Not surprisingly aviation officials are watching things closely. “We have
just entered a new era, and we have got to be concerned about protecting
persons and property,” says Nicholas Sabatini, who is in charge of aviation
safety at America's Federal Aviation Administration (FAA).
As the difference between sophisticated model aircraft equipped with
auto-pilot systems and cameras and commercial UAVs blurs, the FAA is
reconsidering its guidelines for model-flyers. At the moment these basically
amount to keeping unmanned planes in sight at all times and away from
people, buildings and other aircraft. Britain's Civil Aviation Authority is
working with various industry groups to see what new rules may be needed. As
a spokesman points out, UAVs will range from large jet-powered machines
capable of flying across the Atlantic to tiny devices, so regulations will
vary too depending on their size, weight and speed. Below a certain size,
unmanned aircraft could be impossible to regulate. Nor would regulation do
much to remove a chilling worry: that a UAV could be used as a weapon, to
carry explosives or a biological agent.
Blown away
The smallest UAVS are the most intriguing because they will be able to fly
in places where it was never thought aircraft could venture. Just how small
might these machines be? The REMANTA bug has a total wingspan of less than
15cm (six inches). It flies by flapping its wings a bit like an insect. This
means it needs less power than helicopter-type rotors and should be better
able to withstand being blown off-course by wind, says Agnès Luc-Bouhali, a
member of the project team.
Such a device can fly and be controlled remotely, but it could not yet
conduct a mission like that portrayed in Onera's video. “Today, that is a
dream,” admits Ms Luc-Bouhali. But the team is working on it. Miniaturising
power sources and sensors, and fitting REMANTA with systems to operate
semi-autonomously in order to avoid obstacles such as walls are the main
areas of future research and development.
Such concerns also occupy researchers at Harvard University. They are
working on a fly-like robot which weighs only 60 milligrams (0.002 ounces)
and has a wingspan of just three centimetres—about the size of a real fly
and so most unlikely to be noticed. This means going beyond scaling down
existing components, like electric motors, and trying entirely new
manufacturing processes. The Harvard “fly-bot” has flown, but so far only on
a tether from which it gets external power.
A different approach is being tried by a team at Britain's Portsmouth
University working with a company called ANT Scientific. Next summer the
group will enter a robotics competition to be held at a British army
urban-warfare training centre. The Portsmouth team is working on a UAV small
enough to fit on a hand. Charlie Barker-Wyatt, a member of the university
group, says all he can reveal about the device is that it contains sensors,
can remain airborne for about 15 minutes, has a range of 500 metres and
flies like a “hovering and spinning frisbee”.
Such tiny devices are of less concern to safety officials than bigger UAVs
that would cause damage if they hit an aeroplane or crashed to the ground.
Until now UAVs have mostly been confined to conflict zones, no-go military
areas or remote places. Some operate under the same guidelines as for model
aircraft. But they are not welcome in “controlled” airspace, where manned
aircraft fly under air-traffic control. The FAA's Mr Sabatini says his
agency does not want to stifle their development, but insists it must at the
same time maintain safety standards. This means larger UAVs could be
considered “experimental” aircraft and allowed to operate in closely
controlled circumstances. But until they have some ability reliably to
detect and avoid other aircraft they will have to keep clear of controlled
airspace.
Some bigger systems operate like manned aircraft even in remote areas. The
“pilots” of the Predator that crashed in Arizona were in contact with
air-traffic controllers. But NTSB officials were still concerned about UAVs
being flown too much like a computer game rather than as they would be if
their pilots were on board.
Strict operating conditions for bigger UAVs might suit aviation firms, which
are used to regulation and face competition from unmanned aircraft.
Evergreen, a big aerospace group based in Oregon, has set up a UAV operation
within its helicopter division. It offers relatively large and sophisticated
systems for use in long-range operations, like checking on oil rigs, search
and rescue, and wildlife monitoring.
Medium-sized systems might also have to be regulated, especially if used
commercially. In the case of the smallest UAVs, the genie is already out of
the bottle. When such devices are so small they might not even be noticed it
would prove extremely difficult to regulate their use.
Unmanned aircraft will become more common, but how they swarm will depend on
how safely they are used and how people react to the invasion of privacy.
Some UAV missions may not be very welcome at all. “It smacks of Big Brother
if every time you look up there's a bug looking at you,” reckons the FAA's
Mr Sabatini. Time to buy a good fly swat, perhaps.