Rigid robots step aside — a new generation of squishy, stretchy machines is wiggling our way.
n 2007, Cecilia Laschi asked her father to catch a live octopus for
her seaside lab in Livorno, Italy. He thought she was crazy: as a
recreational fisherman, he considered the octopus so easy to catch that
it must be a very stupid animal. And what did a robotics researcher who
worked with metal and microprocessors want with a squishy cephalopod
Nevertheless, the elder Laschi caught
an octopus off the Tuscan coast and gave it to his daughter, who works
for the Sant'Anna School of Advanced Studies in Pisa, Italy. She and her
students placed the creature in a saltwater tank where they could study
how it grasped titbits of anchovy and crab. The team then set about
building robots that could mimic those motions.
Prototype by prototype, they created an artificial tentacle with
internal springs and wires that mirrored an octopus's muscles, until the
device could undulate, elongate, shrink, stiffen and curl in a lifelike
manner1. “It's a completely different way of building robots,” says Laschi.
This approach has become a major research front for robotics in the
past ten years. Scientists and engineers in the field have long worked
on hard-bodied robots, often inspired by humans and other animals with
hard skeletons. These machines have the virtue of moving in
mathematically predictable ways, with rigid limbs that can bend and
straighten only around fixed joints. But they also require meticulous
programming and extensive feedback to avoid smacking into things; even
then, their motions often become erratic or even dangerous when dealing
with humans, new objects, bumpy terrain or other unpredictable
Robots inspired by flexible
creatures such as octopuses, caterpillars or fish offer a solution.
Instead of requiring intensive (and often imperfect) computations, soft
robots built of mostly pliable or elastic materials can just mould
themselves to their surroundings. Although some of these machines use
wires or springs to mimic muscles and tendons, as a group, soft robots
have ditched the skeletons that defined previous robot generations. With
nothing resembling bones or joints, these machines can stretch, twist,
scrunch and squish in completely new ways. They can transform in shape
or size, wrap around objects and even touch people more safely than ever
Building these machines involves
developing new technologies to animate floppy materials with purposeful
movement, and methods for monitoring and predicting their actions. But
if this succeeds, such robots might be used as rescue workers that can
squeeze into tight spaces or slink across shifting debris; as home
health aides that can interact closely with humans; and as industrial
machines that can grasp new objects without previous programming.
Researchers have already produced a wide variety of such machines, including crawling robotic caterpillars2, swimming fish-bots3 and undulating artificial jellyfish4.
On 29–30 April, ten teams will compete in Livorno in an international
soft-robotics challenge — the first of its kind. Laschi, who serves as
scientific coordinator for the European Commission-backed sponsoring
research consortium, RoboSoft, hopes that the event will drive
innovation in the field.
“If you look in
biology, and you ask what Darwinian evolution has coughed up, there are
all kinds of incredible solutions to movement, sensing, gripping,
feeding, hunting, swimming, walking and gliding that have not been open
to hard robots,” says chemist George Whitesides, a soft-robotics
researcher at Harvard University in Cambridge, Massachusetts. “The idea
of building fundamentally new classes of machines is just very
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