OFF Topic: Srinkage

NO men it's not what you are thinking!

AN ENGINE FOR RUNNING MEDICAL MICROBOTS

Doctors have miniaturized almost
everything they need to send robots
inside your brain’s blood vessels to
treat damaged tissue. But making a
motor small enough to squeeze past
blood cells has held things up. Now,
engineers at Monash University in
Australia have built a micromotor that
brings bitty ’bots closer to reality.
Shrunken versions of standard
electric motors, which use spinning
magnets, have traditionally lacked
power or required a bulky gear
box to prevent them from spinning
too fast. So the Monash engineers
decided to power their 0.14-inch-tall
motor, called Proteus, using reverse
piezoelectricity—a phenomenon
that converts an electric charge into
motion—which lets it maintain power
and run at a reasonable speed at any
size. An electrifi ed ceramic element
oscillates up and down, twisting a
springlike rod that turns a tiny ball.
The ball’s rotation could then spin a
fl agellum to help a robot swim.
The group plans to install the
motor in a robot, test it in artifi cial
blood vessels and, by next year, further
shrink Proteus to 1/300 the size
of an ice-cream sprinkle. Making the
minuscule pieces won’t be a problem,
says Brett Watson, a member of the
Monash team, but he says patience
is key: “It’s really hard to put the darn
thing together.”—SUSANNAH F. LOCKE

PS May 09