Microparticles Self-Assemble into Spinning Gears

Self-assembly is common in nature, as living systems are biochemical machines that excel at building and moving their parts. Funded by the National Science Foundation , researchers at University of California San Diego and New York University have developed a new way to mimic self-assembly in the lab, coaxing specially-designed microscopic objects into small, gear-like machines. The building blocks are self-powered microparticles that propel after being activated by light. The researchers designed them to autonomously sense light gradients and navigate in light patterns. They call the result a "machine made of machines."