"Robots are expensive. Mass production would make them cheaper, but standardized robots may not be able to perform specialized tasks. What if, instead of mass-producing robots, you could mass-produce parts of robots and assemble them into the appropriate forms? Mark Yim is at the forefront of this approach, ""modular robots,"" in which many small, identical robots areassembled to form one larger unit. As a graduate student at Stanford, Yim built Polypod, a robot composed of only two different types of modules that was able to move like a Slinky, an earthworm, or a caterpillar. At Xerox, he’s developed a successor, PolyBot, that changes from a rolling loop traveling across flat terrain to an earthworm moving over obstacles. Yim’s goal, though,is far more complex: systems of hundreds to millions of small robots that can reconfigure themselves into the desired form. Such ""morphing"" robots could become the ultimate tool, reshaping to fit the needs of the job at hand."