Using Acoustic Resonators As Thrusters For Small Robots

Researchers led by Junsun Hwang demonstrated acoustic propulsion using Helmholtz resonance, published in Science Advances with a summary from EPFL's School of Engineering. When an external acoustic source matches a chamber's resonance frequency, it produces a jet of air at the chamber's neck. Applications shown include a boat using three resonance chambers for propulsion and steering, and microfliers that hover above an ultrasonic phased array. Angled resonator chambers were also adapted to drive tiny propellers. Because the thrust generated is only a fraction of a Newton, the microflier structures had to be built extremely light, on the order of micrograms, using high-resolution 3D printing across several design iterations.

Source: https://hackaday.com/2026/08/17/using-acoustic-resonators-as-thrusters-for-small-robots. 8 Sync News only summarizes and links out; content copyright belongs to the authors and original sources.