www.servomagazine.com/index.php?/magazine/article/june2011_GeerHead
GEERHEAD
to the two different purposes of
touch. The scientists also sought to
learn whether patients preferred to
be warned verbally by the robot
that they were about to be touched
and what the purpose of the touch
was.
Cody reaches out to touch
the forearm of a subject during
the experiment.
The Robot
Cody is a mobile two-armed
robot created for testing the
robotic nursing assistant paradigm.
Cody’s mobility is enabled by its
Segway base. Cody’s manipulators
consist of MEKA Robotics arms
with each one actuated by seven
series elastic actuators at each of
its seven joints for seven degrees of
freedom and smooth actuation.
Each joint also has virtual viscoelastic springs to ensure that the
robot’s hands stop where they
should.
The wrists are equally
equipped with multiple degrees of
freedom via six-axis force sensors.
The hands — which look like
spatulas — were created using a 3D
printer. The robot touches subjects
with cuttings of towels that have
been wrapped around the hands
and secured.
The body of the robot consists
of a torso with an RX- 28 Robotis
servo on top of that. The robot’s
intelligence consists of two Linux
computers running the popular free
Ubuntu Linux distribution and
software the roboticists coded in
with the Python programming
language. In order for the robot to
touch patients precisely, the
researchers installed a tilting
Hokuyo UTM-30LX and a Point Grey
Firefly camera to gather laser range
data. These are contained in an
XBOX 360 housing.
The robot system includes an
interface on a remote computer so
Cody’s “hand” in motion.
Cody’s robot housings and
electronics (including power to
the Segway), its computers,
and controller box.
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