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Title: Insertion, Retrieval and Performance Study of Miniature Magnetic Rotating Swimmers for the Treatment of Thrombi
Miniature Magnetic Rotating Swimmers (MMRSs) are untethered machines containing magnetic materials. An external rotating magnetic field produces a torque on the swimmers to make them rotate. MMRSs have propeller fins that convert the rotating motion into forward propulsion. This type of robot has been shown to have potential applications in the medical realm. This paper presents new MMRS designs with (1) an increased permanent magnet volume to increase the available torque and prevent the MMRS from becoming stuck inside a thrombus; (2) new helix designs that produce an increased force to compensate for the weight added by the larger permanent magnet volume; (3) different head drill shape designs that have different interactions with thrombi. The two best MMRS designs were tested experimentally by removing a partially dried 1-hour-old thrombus with flow in a bifurcating artery model. The first MMRS disrupted a large portion of the thrombus. The second MMRS retrieved a small remaining piece of the thrombus. In addition, a tool for inserting, retrieving, and switching MMRSs during an experiment is presented and demonstrated. Finally, this paper shows that the two selected MMRS designs can perform accurate 3D path-following.  more » « less
Award ID(s):
2130793 1932572
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Date Published:
Journal Name:
2023 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)
Page Range / eLocation ID:
8454 to 8460
Subject(s) / Keyword(s):
magnetic robot blood clot magnetic manipulation milli-scale robot
Medium: X
Detroit, MI, USA
Sponsoring Org:
National Science Foundation
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