by David Geer
Contact the author at geercom@alltel.net
A Self-Reassembling Robot
Ever seen a robot torn apart only to put itself back together? Jimmy Sastra, a student in the
Modular Robotics Lab at the University of Pennsylvania has. He helped create it. As with
most scientific endeavors, the Robotic Self-Reassembly After Explosion (SAE) project was
a solution to a problem: how to get a robot to reassemble itself after ‘disassembly’ by
‘explosion’ (“Towards Robotic Self-Reassembly After Explosion,” the Modular Robotics Lab,
University of Pennsilvania, Mark Yim, et.al.). Jimmy Sastra, a named author on the paper and
research student at the University, calls an explosion “the rapid randomized disassembly of
a system from a high-energy event.” As shown in the video linked here with, the explosion
is the separation of the robot as students kick it apart, separating it into three parts.
The Self-Reassembling robot is a
precursor to modular, self-configuring robots of the future,
which are envisioned with many
Close-up of cluster with camera module.
10 SERVO 11.2008
thousands of parts and modules that
configure themselves for varying
applications or — as in this case —
reassemble all their parts after
separation by explosion.
In this experiment, the goals of
the robot are to perform a task, suffer
an explosion, reassemble itself, and
continue the original task from where
it left off.
This cluster of five modules shows the
camera module attached, top-side.
The robot is designed to
disassemble along specific, preselected
lines or weakest links between the
modules in a structured fashion. By
ensuring that the robot separates at
these “bonds” between the modules,
the robot absorbs the shock and
disassembles at points where it is
capable of reassembling.
The self-assembly of the robot is
part of a larger plan for self-repair.
This type of self-repair involves
diagnosis of the problem/break
points, a plan for re-assembly, and
an execution of that plan, according
to Yim.
Diagnosis
The robot uses sensors to
determine that it is no longer
connected to itself. The robot consists
of clusters of modules. According to
Jimmy Sastra, the clusters are
connected to each other at certain
modules — using magnets. Each
module face — which is connected to
another module face — has two IR
