- Researchers at the University
of California at Berkeley are building a minuscule robot guaranteed to
give new meaning to the old phrase,``fly on the wall.''
- Known affectionately as ``robofly,'' the gadget is exactly
what its name implies: a flying robot about the size of a housefly. It
even looks a bit like a fly, although it will have four wings instead of
two and one glassy eye instead of two beady ones.
- Uncle Sam, who is bankrolling the project to the tune
of $2.5 million and wants to see robofly airborne by 2004, will add the
flying robot to its espionage toy box.
- ``The potential application of a robot based on a fly
might be, in an urban environment, clandestine surveillance and reconnaissance,''
said Teresa McMullen of the Office of Naval Research.
- In other words, that fly might be a spy. Just the thing
for keeping tabs on terrorists. Or wandering spouses.
- Its creators are not mad scientists but Ph.D.s. They
envision a nifty gizmo that will do all sorts of wonderful things, like
fly through the rubble of an earthquake searching for survivors.
- ``I really do envision,
in every fire station, a jar of robotic insects,'' Michael Dickinson, a
biologist working on the project, said with a perfectly straight face.
``You could scatter them around and have them send a signal when they find
- But why a fly? Because the aerodynamic principles that
keep 747s aloft do not work on such a small a scale.
- ``If we want to develop something with stealth, we have
to look at nature,'' McMullen said. ``There are no man-made objects that
small that can fly.''
- But why a fly? Why not something with a little more pizzazz
like, say, a dragonfly?
- Two reasons, said Ron Fearing, the top gun behind the
micromechanical flying insect. First, dragonflies have four wings.
- ``That automatically doubles the complexity of the project,''
- More importantly, flies, for all their faults, are outstanding
pilots. They can take off and land in any direction, even upside down.
They can change course in just 30-thousandths of a second. And they process
information at speeds that make a supercomputer look like an abacus.
- ``They're the fighter jets
of the animal world,'' Fearing said.
- Robofly will weigh about 43 milligrams -- roughly the
weight of a fat housefly. Its body will be made of paper-thin stainless
steel and its wings of Mylar, which looks and feels a lot like Saran Wrap.
- ``Instead of gears and cogs and cams, we're using pieces
that are more like origami,'' Dickinson said.
- Robofly will be powered by the sun, and a tiny device
called a piezoelectric actuator will flap its four puny wings 180 times
- Fearing and his pals cleared their first big hurdle in
April when Dickinson figured out how flies fly. It was a question that
had perplexed researchers for decades, and Fearing sheepishly admits that
he had no clue how flies fly when he pitched robofly to the Office of Naval
- Lucky for him that Dickinson solved the riddle. Dickinson
discovered that insects use three different wing motions that, taken together,
create backspin and air vortices that create lift. The complexity of the
movement means robofly will need four wings to do what flies do with two.
- That problem solved, Fearing is scratching his head trying
to figure out how to control robofly once it is airborne. After all, there
is not much use for robots that can only hover over a desk.
- ``Flies have 100 million years of evolution to tell them
how to fly,'' Fearing said. ``We're not going to be there instantly.''
- He is hoping to crib from colleagues at California Institute
of Technology in Pasadena who are developing tiny gyroscopes just one millimeter
in diameter. And some of the tricks Caltech researcher Kris Pister is developing
for ``smart dust'' -- which will pack sensors, communicators and computing
power onto tiny silicon motes -- also could come in handy.
- Robofly was hatched in early 1998, when the Office of
Naval Research sought ideas for tiny robots. Fearing, who has been fascinated
by robots since he was a teenager, jumped at the chance.
- He got together with some colleagues who let their imaginations
run wild. Really wild. One idea was for a tiny, walking robot not much
larger than an ant. (``Basically a silicon chip with legs,'' Fearing said.)
Another idea was for a hopping robot modeled after an octopus. And then
there was robofly.
- The Navy loved robofly. It also loved robolobster, now
being built at Northeastern University, and robopike, which swims in a
tank at the Massachusetts Institute of Technology.
- The robomenagerie is the vanguard of biomimetics, a strange
field where scientists reverse-engineer nature's greatest tricks.
- ``There are all kinds of things nature can do that we
don't know how to do yet,'' Fearing said.
- The idea is to copy Mother Nature's nifty tricks -- things
like a lobster's ability to navigate pounding surf or a bat's sonar that
allows it to find mosquitoes in the dark.
- The pint-size, or, in the case of robolobster, quart-size,
robots also represent a move among engineers and researchers toward microrobotics.
- The idea is to use a bunch of little robots to do the
work of one big robot -- or human. The Defense Department likes the idea
of sending robobeasts to do things far too dangerous for humans -- nasty
little tasks like clearing land mines or inspecting nuclear reactors in
- Robot, after all, comes from the Czech word robota, which
- The best example of the microrobotic trend is NASA, which
has embraced the ``smaller, faster, cheaper'' philosophy of sending lots
of little space probes to do the work of one big space probe.
- With a single big robot, it's ``one giant accident, and
you're hosed,'' Dickinson said. ``But if you throw up 1,000 little robots
and lose a few of them, or even half of them, you'll still be getting a
lot of information.''
- While Fearing has been fascinated with robots since high
school, Dickinson is new to the game. He was drafted by the team because
of his expertise in the arcane field of insect aerodynamics but admits
he likes the idea of tinkering with a robot.
- ``A lot of biologists,'' he joked, ``are nerdy geeks
who, but for a twist of fate, would have been engineers.''