Related Experiment Video
Updated: Sep 9, 2025
14:22
Activating Molecules, Ions, and Solid Particles with Acoustic Cavitation
Published on: April 11, 2014
15.2K
Launching by cavitation
Dalei Wang1, Zixiao Liu2, Hongping Zhao1
1National Key Laboratory for Development and Utilization of Forest Food Resources, Zhejiang A&F University, Hangzhou, China.
Science (New York, N.Y.)
|August 28, 2025
Summary
Cavitation is harnessed to launch millimeter-scale devices, achieving high speeds and efficient energy transfer. This novel method enables devices to jump and swim, demonstrating broad applicability for actuators and robotics.
Area of Science:
- Physics
- Materials Science
- Robotics
Background:
- Cavitation, the formation and collapse of vapor bubbles in liquids, is typically destructive.
- However, this phenomenon can be controlled and utilized for mechanical applications.
Purpose of the Study:
- To harness cavitation for energy accumulation and controlled release.
- To develop a novel propulsion method for micro-devices using cavitation.
Main Methods:
- Accumulating energy in superheated liquids by suppressing bubble collapse.
- Utilizing the violent collapse of unstable cavitation bubbles to generate force.
- Testing millimeter-scale devices for launching and swimming capabilities.
Main Results:
- A millimeter-scale device achieved a 1.5-meter jump with 12 m/s peak velocity and 7.14 × 10^4 m/s^2 acceleration.
- The cavitation-based launching demonstrated 0.64% energy efficiency.
- Devices were propelled to swim on water at 12 cm/s.
- The method proved effective across various device materials, liquid media, and environments.
Conclusions:
- Cavitation can be controllably harnessed to generate significant propulsive force for micro-devices.
- This technology offers a versatile platform for developing novel actuators and robotic systems.
- The demonstrated performance metrics highlight the potential of cavitation-driven propulsion.
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