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Research News
Birds Do It, Bees Do It… Now Robots Do, Too
by Nell Boyce

One of the tower robots in Hod Lipson's lab in the process of
replicating itself. The cubes in the tower can twist and move because each one is split in half. Tiny motors and magnets allow the cubes to swivel and hook up with their neighbors. Cornell University

Watch Lipson's Tower Robot Make Copies of Itself

LEGO Bots at Johns Hopkins
At Johns Hopkins University, Gregory Chirikjian has been using LEGOs to
make simple self-replicating robots. Like the machines at Lipson's lab,
these robots can also only put together a few ready-made parts.

Watch a Semi-Autonomous Robot in Chirikjian's Lab Replicate Itself

Morning Edition, May 12, 2005 • For years, scientists have dreamt of
Making robots that can self-reproduce. Someday, such a machine could be sent to explore a distant planet, where it could clone itself. Now, researchers say they've come up with primitive robots that can self-replicate.
In the current issue of the journal Nature, Hod Lipson from Cornell
University describes robots in his lab with a limited ability to
self-reproduce. The machines aren't the humanoid contraptions many
people conjure when they think of robots -- Lipson's robots consist of a stack of three white plastic cubes that stand as a simple tower.

Each cube has an electronic brain that holds a blueprint for building
new towers. If you feed one of these robot towers new cubes, it will make a copy of itself in just a couple of minutes.

Lipson says his robot is still way too dependent on humans to take any
kind of interplanetary journey. "They're dependent very much on having cubes supplied in a very particular place and particular time," Lipson says.

"They have a lot of constraints."