The CHIMP robot's joints are drive joints that come in
four different sizes suited to the torque necessary at each
respective joint placement in the
robot's arms and legs. The CMU
National Robotics Engineering
Center (NREC) designed these drive
The drive joints consist of
frameless motors combined with
torque-limiting clutches, integrated
brakes, and gearing. These
components afford the robot's joints
precise control and high power
density. The most powerful joint of
the four can allow the robot to curl
The advantage of frameless
motors is that they enable high
output and roboticists can embed
them directly into robot mechanics;
torque-limiting clutches address
torque overload without loss of power.
Each arm has seven joints while each leg has six. The
roboticists have equipped the CHIMP with a total of 39
motors, including motors that turn two laser radars which
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SERVO 05.2014 13
Monthly coverage of commercial, unique, and military robotics.
CHIMP No Chump
The CMU Highly Intelligent Mobile
Platform (CHIMP) is a life-sized five foot
two inch humanoid robot built for specific
tasks including rescue missions and
laborious tasks. The 400 lb gearbox gorilla
moves on 12 inch tank treads fitted to
each of its four appendages.
While the CHIMP travels on all fours, it
can also stand on two legs to stabilize
itself while using its end effectors to
manipulate items such as power tools and
turn valves, and effect other relatively
complex yet useful tasks.
Unlike Johnny 5 of movie fame — which
was limited to traveling on two larger
treads — the CHIMP has the option of
traveling on two or four foot-like treads or
even of walking. The robot can climb
stairs walking with a human-like gait, and
it can also remain standing regardless of
power loss or computation issues.
The robot is specifically designed to
mitigate disasters while working in
environments that, though better suited
to human laborers and engineers, are
too dangerous for them.
The statically stable walking robot has
long arms — that when combined — offer
a wingspan of nearly 10 feet. This earns
it an ape- or gorilla-like posture with
hanging arms. The robot's disaster
response capabilities include clearing
debris and handling fire hoses, as well
as navigating difficult terrains.
The CHIMP robot turns a large
valve to open or close it. This
capability will be extremely critical
to disaster recovery in