Page 72 - The Economist20171214

72 Science and technology The Economist December 16th 2017
2 Dr Benedict reckons cyclocopters are of Pennsylvania did indeed manage to
about two years away from commercial make drones fly together in co-ordinated
production. Once that happens they could formations without hitting each other.
displace polycopters in many roles, not They look good when doing so—but, to
justmilitaryones. Buttheyare notthe only some extent, what is seen is an illusion.
novel technologyin which MAST hasbeen The drones are not, as members of a
involved.Theprogrammehasalsoworked swarm ofbees or a flockofbirds would be,
on robots that hop. relying on sensory information they have
One of the most advanced is Salto, de- gathered themselves. Instead, GRASP’s
veloped by the Biomimetic Millisystems drone swarms employ ground-based sen-
Laboratory at the University of California, sorstotrackindividual dronesaround, and
Berkeley. Salto (pictured) is a monopod a central controllerto stop them colliding.
weighing 98 grams that has a rotating tail That is startingto change. Afarewell de-
and side-thrusters. These let it stabilise it- monstration by MAST, in August, showed
self and reorient in mid-leap. That gives it three robots(two on the ground and one in
the agility to bounce over uneven surfaces the air) keeping station with each other us-
and also to climb staircases. ing only hardware that was on board the
Salto’s speed (almost two metres a sec- robots themselves. This opens the way for
ond) puts huge demands on its single leg. larger flocks of robots to co-ordinate with-
Ron Fearing, one ofthe electrical engineers out outside intervention.
developing it, puts things thus: “imagine a Moreover, as that demonstration
cheetah running at top speed using only showed, when drones and other robots
one leg, and then cut the amount of time can routinely flock together in this way,
that leg spends on the ground in half.” As they will not necessarily be birds of a
with cyclocopters, the materials and pro- Ready to spring into action feather.“Heterogeneousgroup control” isa
cessing power needed to do this have only new discipline that aims to tackle the
recently come into existence. small drones that can “ingress and egress thorny problem of managing units that
DrFearingsays Salto and its kin are qui- into buildings and navigate within those consist ofvarious robots—some as small as
eter than aerial drones and can operate in buildingsathigh speeds”. Some ofthathas a postage stamp, others as large as a
confined spaces where flying robots already been done. In June DARPA report- jeep—as well as human team members.
would be disturbed by turbulence reflect- ed that polycopters souped up by the FLA Swarms will also need to be able to break
edfromthewalls.Theycanalsotravelover programme were able to slalom through up into sub-units to search a building and
terrain, such as collapsed buildings, that is woodlands, swerve around obstacles in a then recombine once they have done so,
off-limits to wheeled vehicles. Salto still hangar and report back to their starting- all in a hostile environment.
needs work. In particular, it needs to be point, all by themselves. Such things are the goals of DCIST. The
able to cling more effectively to what it first tranche of grants to these ends, some
lands on. Dr Fearing uses the analogy of a Unityis strength $27m of them, has already been awarded
squirrel leapingfrom branch to branch. Ar- The next challenge—the one that people totheUniversityofPennsylvania, the Mas-
riving at the next branch is only half the like DrRussell particularlyworryabout—is sachusetts Institute of Technology, the
battle. The other halfis staying there. Once getting the robots to swarm and co-ordi- Georgia Institute of Technology and the
that is solved, though, which it should be nate their behaviour effectively. Under the University of California, Berkeley. When
in the nextyearortwo, small non-flying ro- aegis of MAST, a group from the General DCIST itself wraps up, probably in 2022,
bots that can go where their wheeled, or Robotics, Automation, Sensing & Percep- the idea of Slaughterbots may seem a lot
even track-laying, brethren cannot should tion (GRASP) laboratory at the University less fictional than it does now. 7
become available forpractical use.
Bouncingovertherubbleofacollapsed
building is not the only way to explore it. Geology and tourism
Anotheristo weave through the spaces be-
tweenthedebris.ResearchersattheBiomi- Pillars of salt
meticMillisystemslabareworkingonthat,
too. Their solution resembles a cockroach.
Itsbodyisbroad and flat, which gives itsta-
bility but also permits it to crawl through
narrow spaces—if necessary by going up
on one side. Should it tip over whilst at-
tempting this, it has wing-like extensions it Awayto predictsinkholes underspas nearthe Dead Sea
can use to flip itselfupright again. HE Dead Sea is, as its name implies, far Until now, it has been impossible to
Getting into a building, whether col- T too salty to be of use to fishermen or predict more than a few weeks in advance
lapsed or intact, is one thing. Navigating farmers. Butitsmineral-rich watersare val- where a sinkhole will appear. But, as he re-
around it without human assistance is ued by the owners of the spas that thrive ports in Geology, Meir Abelson ofthe Geo-
quite another. For this purpose MAST has along its shores in Israel, Jordan and the logical Survey of Israel thinks he can
been feeding its results to the Defence Ad- Palestinian territory of the West Bank. The change that. Employingburied monitoring
vanced Research Projects Agency (DARPA), spa industry, however, facesa threat from a devices, he believes he can forecast where
America’s main federal military-research plague of sinkholes that have struck in re- such holes will form several years before
organisation. According to Brett Piekarski, cent years. These have damaged roads and they actually do so.
who led MAST and is now in charge of buildings at Ein Gedi beach, in Israel, and Most of the more than 6,000 sinkholes
DCIST, the Fast Lightweight Autonomy hit the Mineral Beach Spa in Mitzpe Sha- that have struckthe west coast ofthe Dead
(FLA) programme at DARPA will continue lem, an Israeli settlementin the West Bank, Sea recently are the result of that sea being
MAST’s work with the aim of developing so hard that it is unusable. starved ofwaterasthe riversflowing into it 1