Penn/Michigan programmable microrobot

Overview

The smallest fully programmable, autonomous robot reported so far, about the size of a single-celled paramecium. Marc Miskin's lab at Penn built the body and propulsion, and David Blaauw's lab at Michigan built the computer. They swim by electrokinetic propulsion, where electrodes set up an electric field that pushes ions, and the ions drag the surrounding water. Solar cells covering most of the chip supply about 75 nW. One LED powers the robot and a second LED sends programs as flashes, starting with a passcode so each robot type loads only its own code. The custom 11-bit instruction set packs sensing, motion and reporting into single commands to fit the tiny memory.

The Science Robotics paper (December 2025) showed robots that measure temperature and report it by wiggling in a Manchester-coded pattern read under a microscope, likened to a honeybee dance. Programmed robots also climbed toward warmer water on their own. A companion PNAS paper (July 2025) described the propulsion, with simpler robots swimming waypoints and swarms at up to one body length per second. The work follows Miskin's 2020 Nature paper on mass-produced walking microrobots powered by laser light. Those walkers move at a few micrometers per second and need bright light to work. An abstract for a May 2026 MRS Spring Meeting talk described early work on a next-generation chip with more memory, robot-to-robot communication and localization. No medical or human use has been tested.