Micro-UFO (Untethered Floating Object): A Highly Accurate Microrobot Manipulation Technique

Area of Science:

• Robotics
• Biomedical Engineering
• Materials Science

Background:

• Untethered microrobot manipulation using magnetic forces is a rapidly developing research area.
• Potential applications exist in medicine and biology, requiring precise control.
• Existing methods face challenges with friction and control accuracy.

Purpose of the Study:

• To present a new microrobot manipulation technique with nano-level positional accuracy.
• To eliminate friction between the microrobot and substrate surface.
• To enable precise 3D movement of microrobots in liquid environments.

Main Methods:

• Utilized diamagnetic levitation for microrobot manipulation.
• Employed finite element method (FEM) simulations (COMSOL 5.3) to determine magnetic forces.
• Verified simulation results with experimental data for levitation height and working range.
• Analyzed phase difference between magnets to understand drag force effects.

Main Results:

• Achieved high precision (nano-level) positional accuracy in liquid environments.
• Established a stable working range for the microrobot between 30 µm and 330 µm.
• Demonstrated accurate trajectory following (<1 µm average error) at various speeds and heights.
• Successfully manipulated microrobots in three dimensions without bulky magnets.

Conclusions:

• The presented diamagnetic levitation technique offers a promising approach for precise microrobot control in liquids.
• This method overcomes surface friction, enabling high-accuracy locomotion for potential biomedical applications.
• The technique is effective without requiring strong electromagnets or large permanent magnets.