bots IN BRIEF
You may not be able to tell,
but the rat in the photo that isn't a
robot is seriously depressed.
Hopefully, you're asking
yourself why anyone would care if
a rat is depressed, or design a
robot that exists only to instill
depression in rats. Fortunately,
there's a simple answer: We need
depressed rats to be able to test
drugs that treat depression. Before
trying drugs out on humans, they
get tested on animals, and that requires a bunch of depressed
There are already some accepted ways to turn a normal
rat into a depressed rat. For example, you can force it to
swim for long periods, or you can put it into a box and give it
electric shocks. Do these things often enough, and you'll be
left with one seriously unhappy rat. The problem with these
methods is that humans don't usually experience depression
that is caused by prolonged swimming and shocks, so
researchers at Waseda University in Tokyo are trying to come
up with a more accurate model by causing depression in rats
with other (robotic) rats.
This rat robot — called WR-
3 — is basically an attack robot. It
has three modes or "behavior
generation algorithms" which
include chasing, continuous
attacking, and interactive attacking.
Chasing means that WR- 3 will
attempt to maintain a minimum
distance from the rat but not
actually attack it. Continuous
attacking is, well, continuous
attacking with aggressive body
motions and physical contact.
Interactive attacking only attacks the real rat whenever it
moves at a set distance.
Experiments on different groups of rats of different ages
showed that the most effective means of instilling depression
(measured by overall listlessness) was to constantly harass
young rats and then intermittently harass them again when
they got older. Doing it this way apparently is a better overall
model for depression than other methods. So, that's good
news for drug testing and bad news for lab rats.
A Novel Method to Develop an Animal Model of Depression
Using a Small Mobile Robot is available online at
752319 if you want to read it.
The Blind Juggler is a robot that is able to juggle a ball on a paddle. The robot does
this without any sensing; there are no cameras, no microphones, or any other sensors
that could tell the robot where the ball is. That’s right. This robot has no hands, no eyes,
no sensors, and manages to juggle a ball while swinging back and forth using a single
linear actuator. Let me reiterate: no sensors. Imagine yourself juggling a ball blindfolded.
It’s no easy task!
How does the robot do this? The key elements are the shape of the paddle and how
the robot strikes the ball. The developers used mathematical analysis to learn which
shape and motion would make “sensorless” juggling possible. What they found was that a
slightly concave paddle keeps the ball centered, and that a decelerating motion keeps the
ball in the air.
Find out more at www.blindjuggler.org/the-blind-juggler.
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