Conduction Electrohydrodynamics with Mobile Electrodes: A Novel Actuation System for Untethered Robots

Area of Science:

• Robotics
• Fluid Dynamics
• Electrical Engineering

Background:

• Electrohydrodynamics (EHD) enables direct conversion of electrical to mechanical energy in fluids.
• Untethered robots require innovative power sources for miniaturized applications.

Purpose of the Study:

• To design and test a millimeter-scale untethered robot utilizing EHD with mobile electrodes.
• To explore the feasibility of harvesting energy from external electric fields for robotic actuation.

Main Methods:

• A novel millimeter-scale untethered robot was designed, functioning as an inverted sail-boat.
• The robot's thrust was generated on a submerged sail using mobile electrodes and an external electric field.
• Experimental computation of the diffusion constant confirmed movement was not due to thermal fluctuations; kinematic and dynamic responses were characterized under varying voltages.

Main Results:

• The study successfully demonstrated the propulsion of an untethered robot using EHD.
• Kinematic and dynamic responses were characterized, showing feasibility across different applied voltages.
• Experimental diffusion constant confirmed non-thermal fluctuation-driven motion.

Conclusions:

• Electrohydrodynamics with mobile electrodes is a viable method for powering untethered robots.
• This research provides foundational evidence for developing EHD actuation systems for mobile and soft robotics.
• The developed system shows promise for future advancements in micro-robotics and compliant actuators.