One of the biggest challenges with
swarms of robots is
deploying the swarm itself.
Even if the robots are
relatively small and simple,
you’re still dealing with a
whole bunch of them, and
every step in building the
robots or letting them
loose is multiplied over the entire number of bots in the
swarm. If you’ve got more than a few robots to handle, it
starts to get crazy.
The dream for swarm robotics is to be able to do away
with all of that, and just push a button and have your swarm
somehow magically appear. We’re not quite there yet, but
getting awful close.
Researchers from the Wyss Institute for Biologically
Inspired Engineering at Harvard presented a paper recently
demonstrating an autonomous collective robotic swarm that
can be manufactured in a single flat composite sheet. On
command, they’ll rip themselves apart from each other, fold
themselves up into origami structures, and head off on a
mission en masse.
The sheet itself consists of six layers, which are all
automatically laser machined. A pre-stretched polystyrene (or
PSPS) layer (a kind of shape-memory polymer) is in the
between layers of copper
circuits etched into polyimide
sheets, with paper substrates
for support. The PSPS is where the magic happens.
When heated above 100°C (which can be done by
running a 2. 5 ampere current through the copper circuitry), it
shrinks, which is what powers the robot’s self-folding
Otherwise, each robot consists of some discrete
electrical components that have to be placed by hand, but
according to co-author, Michael Tolley, “We foresee
straightforward ways to automate these steps.”
Self-folding robots that use shape-memory polymers have
been done before, but the challenge with them is to
accurately control the folding. To address that issue, the
The final thing that sets these self-folding bots
apart is their ability to go from a single continuous
sheet to a swarm of discrete robots. Self-folding joints
that are designed to prevent folding causes the PSPS
to instead rip itself apart allowing each robot to split
off by itself, where its vibration motors can help it
buzz along flat surfaces seeking sources of light.
There are four robots in this sheet, and they’re pretty
darn near two dimensional. Want more robots? No
problem, just make the sheet bigger.
All images courtesy of
bots IN BRIEF
24 SERVO 12.2016