May 12, 2005— Self-reproduction is no longer limited to biological systems. A new modular robot designed at Cornell University has the ability to construct another robot identical to itself, report scientists in the current issue of Nature.

Although the mechanics involved are simplistic compared to those found in living systems, more sophisticated versions could one day self-replicate — or at the very least self-heal — in realms such as deep space where human intervention might be impossible.

"We have shown a whole family of robots that can construct a working copy of themselves," said team leader Hod Lipson, assistant professor of mechanical and aerospace engineering and computing and information science.

The self-replicating machine consists of plastic modular cubes four inches square that are split diagonally and can swivel on a central joint 120 degrees in two directions.

A microprocessor in each cube contains a unique program that specifies a sequence of actions an individual module must perform in order for the robot as a whole to build another robot.

For example, one command might instruct the cube to rotate 120 degrees when its sensors detect that its magnets have connected with a molecube on its right side.

A robot comprised of many cubes can bend, split in two, pick up spare cubes, drop others off, rotate and essentially reconfigure itself to assemble another robot. And because it can take on different shapes, it can be useful for performing different tasks.

"If you got a collapsed building, you could have a robot transform itself into the shape of snake and then later reconfigure into a dome to protect the person," said mechanical engineer Mark Yim of the University of Pennsylvania, who builds and tests modular robots.

Such a robot could also come in handy during space explorations, where damage or malfunction far from human contact might otherwise render the machine useless.

And it could be more economical, said Lipson, to send the molecubes to their destination where they would assemble into a robot appropriate for the territory.

For now, Lipson and his team are thinking of the immediate future and how to build a robot with specialized modules, such as ones that function as a gripper, a camera, or a cargo container and that can perform a useful task.

It seems that for the time being, biology still has the upper hand.