EPFL scientists build tiny drones propelled by sound waves
Swiss scientists at EPFL have built tiny drones that move using sound waves instead of motors.
By harnessing a physics trick called Helmholtz resonance, these drones use vibrations inside small hollow spaces to create thrust and glide through air or water using hollow cavities instead of motors, gears or magnetic parts.
EPFL cavities steer 1cm boats
The secret is in their circular or bell-shaped cavities. When certain sound frequencies hit these shapes, they push out focused jets of air, letting the boats steer around obstacles and follow programmed paths.
The team even got 1-centimeter model boats to zip around just by tuning the sound.
As lab head Selman Sakar puts it, combining more of these sound-sensitive cavities could someday lead to robots that change shape or movement just by listening.