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AN ARM UP ON COMPETITION
Aaron Edsinger of Meka Robotics, has announced an entirely new
company called Redwood Robotics — a joint venture between Meka
Robotics, Willow Garage, and SRI International. While Redwood has
apparently been in the works for about a year, Edsinger wasn't ready to
commit to much as far as what the new company will actually be
working on. However, here's what we know:
Redwood will be building the "next generation arm" for robots.
Edsinger wants to create an arm that does for robotics what the Apple II
did for computers: Get the hardware out of factories and into homes. In
other words, something that's simple to program, inexpensive, and safe
to operate alongside people. Specifically, they'll be working on a "new type of device" with "new types of interfaces," providing
"product solutions for integrators, developers, and enterprise customers" who (we'll assume) will then sell the arms with
software or firmware to end users. Long term, Redwood wants to be the "arm merchant for emerging personal and service
robot markets." So, when you buy your robot butler in a few years, it'll be from some company that isn't Redwood, but
Redwood hopes it will supply that robot's arms to the company you do buy it from.
Redwood Robotics isn't the only company that's working on low cost robot arms. The other big name in this space is
Heartland Robotics, a stealthy venture-backed startup founded by Rodney Brooks. Last we heard (Dec ‘ 10), Heartland was
working on a human-safe robot for industrial assembly and packaging that reportedly would cost less than US $5,000.
Visitors to Heartland describe a robot that looks like a human from the waist up, with a torso, either one or two arms
with grippers, and a camera where you might expect the head to be. The robot is on a rolling base rather than legs. It can be
moved around but doesn’t move autonomously. The arm and gripper can be quickly trained to do a repetitive task just by
moving them — no software code required. Heartland targets industrial markets, while Redwood seems to be focused on
personal and service robotics.
WHAT A KICK!
For some reason, roboticists seem to enjoy testing their creations by kicking
them, punching them, shoving them, and even striking them with baseball bats and
heavy pendulums. (All in the name of science, of course.) If we want robots that can
do chores around the house, care for the elderly, or (if you're a DARPA program
manager) drive trucks and crash through walls, then we need robots with actuators
that are both fast and strong. The problem is actuators based on electrical motors can
only deliver a limited amount of power, and the alternative — hydraulics — requires
bulky pumps and can be difficult to control. Junichi Urata and his colleagues at the
University of Tokyo's JSK Lab, led by Professor Masayuki Inaba, are working on a
possible solution. They've developed a high torque, high speed robotic leg based on a
novel electrical actuation system. Their robot uses high voltage and high current liquid-cooled motor drivers that get their
power from a 13. 5 farad capacitor system. Why a capacitor? Because it can supply lots of current very fast and reliably —
something that batteries are not good at. The researchers modified an
existing HRP3L (developed by Kawada Industries) to create their robot
which they call HRP3L-JSK. Thanks to the capacitor-powered motor
drivers, the robot's Maxon 200 watt brushless motors (modified to be
liquid-cooled) can achieve instantaneous speeds of over 1,000 degrees
per second and 350 Nm of torque on the robot's knee joint. This
capability allows the 53 kg robot to react to disturbances (in this case,
kicks, knee strikes, and other abuse from researchers) and even jump
44 centimeters off the ground (though the landing part will need work).
The robot relies on a new balance control system that detects
disturbances and computes 170 foot placement possibilities in one
millisecond, choosing the best candidate to keep the robot from falling.
The new method is a collaboration between the JSK team and
researchers from Japan's National Institute of Advanced Industrial
Science and Technology (AIST).
Urata, who recently received a Ph.D. degree for his HRP3L-JSK
work, now has his eyes on the DARPA Robotics Challenge.
72 SERVO 06.2012