Tiny, winged machines

Insect-sized robots can mimic the hovering and darting of flies.

Flies have long been admired for their aerial agility, but technical limitations in miniaturization have hindered attempts to replicate this in similar-sized robots. Kevin Ma and his colleagues at Harvard University in Cambridge, Massachusetts, have invented a specialized laser-manufacturing process that allowed them to create tiny composite structures, including mechanical wings and flight muscles. The researchers used the components to build 80-milligram robotic flies with flapping frequency, wing stroke and energy use similar to that of real flies.
 The mechanical flies (pictured) were capable of controlled flight manoeuvres and hovering in place. The work could open the door to additional innovations in miniaturized machines.

Nature 497, 161