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Planar magnetic microswimmers are well-suited for in vivo biomedical applications due to their cost-effective mass production through standard photolithography techniques. The precise control of their motion in diverse environments is a critical aspect of their application. This study demonstrates the control of these swimmers individually and as a swarm, exploring navigation through channels and showcasing their functional capabilities for future biomedical settings. We also introduce the capability of microswimmers for surface motion, complementing their traditional fluid-based propulsion and extending their functionality. Our research reveals that microswimmers with varying magnetization directions exhibit unique trajectory patterns, enabling complex swarm tasks. This study further delves into the behavior of these microswimmers in intricate environments, assessing their adaptability and potential for advanced applications. The findings suggest that these microswimmers could be pivotal in areas such as targeted drug delivery and precision medical procedures, marking significant progress in the biomedical and micro-robotic fields and offering new insights into their control and behavior in diverse environments.
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This content will become publicly available on December 1, 2026
Surface motion dynamics and swimming control of planar magnetic microswimmers
Abstract Planar magnetic microswimmers offer substantial potential for in vivo biomedical applications, owing to their efficient mass production via photolithography. In this study, we demonstrate the effective control of these microswimmers using an open-loop approach in environments with minimal external disturbances. We investigate their surface motion characteristics through both theoretical modeling and experimental testing under varying magnetic field strengths and rotation frequencies, identifying regions of stable and unstable motion. Additionally, we analyze how field frequency and strength influence surface motion speed and identify the frequencies that promote stability. Open-loop control of surface motion in fluid environments and swimming in channels is also demonstrated, highlighting the operational flexibility of these microswimmers. We further demonstrate swarm motion for both swimming and surface operations, exhibiting larger-scale coordination. Our findings emphasize their potential for future applications in biomedical engineering and microrobotics, marking a step forward in the development of microscale robotic systems.
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- Award ID(s):
- 2123824
- PAR ID:
- 10600614
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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