Scientists create robots smaller than a grain of salt that can think

Researchers at the University of Pennsylvania and the University of Michigan have built the smallest fully programmable autonomous robots ever created. These microscopic machines can swim through liquid, sense their surroundings, respond on their own, operate for months at a time, and cost about one penny each to produce.

Each robot is barely visible without magnification, measuring roughly 200 by 300 by 50 micrometers. That makes them smaller than a grain of salt. Because they function at the same scale as many living microorganisms, the robots could one day help doctors monitor individual cells or assist engineers in assembling tiny devices used in advanced manufacturing.

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