ARMED AND READY
HDT Global has just introduced some new robotic limbs to give
explosive ordnance disposal (EOD) robots like PackBots and Talons a helping
hand (or two) when it comes to complex and delicate tasks like defusing
bombs. This is a very good idea, since just poking high explosives with a
simple gripper doesn't always work out the way everyone would like.
The MK2 limbs can be mounted either singly or as a dual-arm torso on
top of an EOD robot, replacing the much simpler open/close gripper
systems. Instead of grippers, MK2 comes with actual jointed arms and hands
with four degrees of freedom and an opposable thumb. The idea is to make
the system similar enough to human arms and hands so that an operator
can do just about everything they'd want to do with their own arms and
hands while still staying as far away as possible from things like bombs.
The full torso offers a total of 27 degrees of freedom in a package that
only weighs 23 kilograms ( 51 pounds). These arms are actually more
muscular than they look. Together, they can lift 50 kilograms (110 pounds)
with approximately the same speed as a human, and they're dexterous
enough to unzip backpacks, disassemble complex devices, and even use
While there's no doubt that the HDT arm (or arms) are more versatile than the standard arms that come with Talon
robots or PackBots, the HDT's hardware is also more expensive. It's ruggedized and watertight, of course, but since it's a more
complex system overall, more things can go wrong. These sorts of things are always trade-offs, though, and considering how
much more the MK2 arms are capable of, it seems likely that they'll find a place in a robot arsenal doing something useful;
namely, risking getting blown up so that we humanoids don't have to.
ROBOSQUIRREL ACTS NUTS
Animals generally tend to treat robots with either indifference or — more commonly — curiosity. After all, robots are
clearly not food, and they're not usually threatening. So, more often than not, animals are satisfied to just try and figure out
what they are. Turns out, however, if you build a robot that's deliberately designed to provoke an animal, that actually works out
pretty well. Meet RoboSquirrel.
RoboSquirrel is modeled (very) closely after a ground squirrel, and features a real squirrel skin, heated innards, and a
heated and movable tail. RoboSquirrel even sleeps in a squirrel bedding to make it smell just like the real thing.
Why go to all this trouble? Well, researchers from San Diego State University's Behavioral Ecology Lab are trying to figure
out how the squirrels interact with their nemesis — rattlesnakes.
Ground squirrels and rattlesnakes have been going at it for a long time and each has done its level best to try to out-evolve the other, resulting in a continuously changing stalemate. Since
the snakes are predators, the squirrels arguably have the harder job, but
they've developed a resistance to rattlesnake venom and this cool tail-flagging behavior that might help to distract or confuse the snakes. To
determine what the deal is from the perspective of the snake,
RoboSquirrel gets sent into striking range of a wild rattler, and then
either does or does not flag its tail, according to Bree Putman, a
member of the RoboSquirrel project.
While the research is still in preliminary stages, RoboSquirrel does
seem to suggest that tail-flagging has some sort of effect on the snakes,
possibly discouraging them from striking. The research group is already
planning for the deployment of RoboSquirrel 2.0 later this summer, and
they've got a RoboKangarooRat in the works, as well.
26 SERVO 05.2012