The new work, from MIT’s Center for Bits and Atoms (CBA), builds on years of research, including recent studies demonstrating that objects such as a deformable airplane wing and a functional racing car could be assembled from tiny identical lightweight pieces — and that robotic devices could be built to carry out some of this assembly work. Now, the team has shown that both the assembler bots and the components of the structure being built can all be made of the same subunits, and the robots can move independently in large numbers to accomplish large-scale assemblies quickly.

A fully autonomous self-replicating robot assembly system capable of both assembling larger structures, including larger robots, and planning the best construction sequence is still years away, Gershenfeld says. But the new work makes important strides toward that goal, including working out the complex tasks of when to build more robots and how big to make them, as well as how to organize swarms of bots of different sizes to build a structure efficiently without crashing into each other.

As in previous experiments, the new system involves large, usable structures built from an array of tiny identical subunits called voxels (the volumetric equivalent of a 2-D pixel). But while earlier voxels were purely mechanical structural pieces, the team has now developed complex voxels that each can carry both power and data from one unit to the next. This could enable the building of structures that can not only bear loads but also carry out work, such as lifting, moving and manipulating materials — including the voxels themselves.

"Building self-replicating systems is a classic challenge not just in science, but even in the science fiction literature — something that only nature has really achieved so far, so this is extremely exciting work," says Sandor Fekete, a professor of algorithmics in the Department of Computer Science at Technical University Braunschweig, Germany, who was not associated with this work.

(Via MIT News.)

One of the earliest science fictional references to the idea of robots that build other robots is The Mechanical Mice, a 1941 short story by Maurice G. Hugi. He describes the robot mother, a device able to scavenge materials and parts to recreate itself:

He said, "The Robot Mother! That's what I made - a duplicate of the Robot Mother. I didn't realize it, but I was patiently building the most dangerous thing in creation, a thing that is a terrible menace because it shares with mankind the ability to propagate. Thank Heaven we stopped it in time!"

The first scientist to write about self-reproducing automata was John von Neumann, who delivered a lecture in 1948 called "General and Logical Theory of Automata" at a symposium in Pasadena, California. Science fiction appears to have anticipated this development.

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