Water Skating Miniature Robot Propelled by Acoustic Bubbles

Area of Science:

• Robotics
• Microfluidics
• Acoustic Engineering

Background:

• Miniature robots are crucial for exploring confined and hazardous environments.
• Surface tension and microfluidic phenomena offer unique propulsion opportunities.

Purpose of the Study:

• To design and demonstrate a miniature robot capable of skating on water.
• To investigate acoustic bubble-induced microstreaming for robot propulsion and maneuverability.

Main Methods:

• Fabrication of a miniature robot using extruded polystyrene insulation (XPS) and Teflon tubes.
• Generation of propulsion via acoustic excitation of trapped gaseous bubbles, inducing microstreaming.
• Systematic testing of linear and rotational motion at varying frequencies and voltages.

Main Results:

• Propulsion velocity is directly proportional to applied voltage.
• Optimal propulsion occurs at specific resonant frequencies, dependent on bubble volume and tube length.
• Demonstrated selective bubble excitation for controlled maneuvering and 2D navigation.

Conclusions:

• The water-skating robot effectively utilizes acoustic microstreaming for locomotion.
• The robot exhibits controllable linear, rotational, and 2D navigation capabilities.
• This technology is promising for environmental monitoring in small, complex aquatic settings.