Three separated clusters attempting to
locate each other and re-join.
Two clusters making ground
toward each other.
Two clusters even closer. The third
cluster is shown in the background.
(infrared) pairs: one is an emitter and
one is a detector.
The pairs check to see whether
they can communicate with the set of
pairs on the other module facing
them. If they can’t communicate with
each other, they know they have been
“exploded” (disconnected from each
The single robot returns to its original
other). The IR pairs also inform the
modules as to who their neighboring
Each cluster consists of five
modules screwed together. Each
module in a cluster also uses IR pairs
to determine which module is its
neighbor. Each cluster talks to itself
using a CANbus, which is a global
bus connecting the internal
Each module in the robot
contains a microcontroller that
controls the angle of the module.
Each of three camera modules
employs a vision localization
processor. The camera module also
contains a communications unit.
The camera module includes a
three-axis accelerometer so that it may
know its orientation; whether it is
standing or lying down. “After we kick
the robot to explode it, it might be
upside down. Using the accelerometer, it will self-right the cluster or the
entire robot as needed. It needs to
self-right in order to locomote to
connect to the other clusters,”
Each of three clusters has an
additional stand-alone controller
that communicates with the microcontrollers in the camera modules.
Each microcontroller runs its own
state machine (software), according to
Sastra. If the robot is fully assembled,
it walks. If it is assembled, one of the
three stand-alone controllers in one of
the three clusters will become the
master controller over the other
clusters and control the walking task.
As the robot walks, it uses its IR
More Entertainment Than A Political Debate!
Three clusters re-united into a
By the time this is published,
Jimmy Sastra and the self-reassembling robot team will have
attended the Wired NextFest at
which they planned to demo the
robot. “It’s a well attended event,”
The robot is a collaboration of
various labs at the University of
Pennsylvania, including CJ Taylor’s
lab, which worked on the vision
technology and Mark Yim’s lab, which
worked on the modular robotics.
Other researchers involved
in the project include Babak
Shirmohammadi, Michael Park, and
Michael Dugan, all of the University
of Pennsylvania. Sastra notes that
while there are about eight different
modular robotics labs around the
world, the robot from the University
of Pennsylvania is a very unstructured
demonstration of the technology,
and it uses a high impact means of
disassembling. Probably the closest
to this robot is in a lab in Japan,
called the Entran robot, which can
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