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Millimeter-scale magnetic rotating swimmers have multiple potential medical applications. They could, for example, navigate inside the bloodstream of a patient toward an occlusion and remove it. Magnetic rotating swimmers have internal magnets and propeller fins with a helical shape. A rotating magnetic field applies torque on the swimmer and makes it rotate. The shape of the swimmer, combined with the rotational movement, generates a propulsive force. Visual feedback is suitable for in-vitro closed-loop control. However, in-vivo procedures will require different feedback modalities due to the opacity of the human body. In this paper, we provide new methods and tools that enable the 3D control of a magnetic swimmer using a 2D ultrasonography device attached to a robotic arm to sense the swimmer’s position. We also provide an algorithm that computes the placement of the robotic arm and a controller that keeps the swimmer within the ultrasound imaging slice. The position measurement and closed-loop control were tested experimentally.
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This content will become publicly available on August 28, 2025
Open-Source CFD Simulation of Magnetic Rotating Swimmers with Experimental Validation
Many potential medical applications for magnetically controlled tetherless devices inside the human body have been proposed, including procedures such as biopsies, blood clot removal, and targeted drug delivery. These devices are capable of wirelessly navigating through fluid-filled cavities in the body, such as the vascular system, eyes, urinary tract, and ventricular system, to reach areas difficult to access via conventional methods. Once at their target location, these devices could perform various medical interventions. This paper focuses on a special type of magnetic tetherless device called a magnetic rotating swimmer, which has internal magnets and propeller fins with a helical shape. To facilitate the design process, an automated geometry generation program using OpenSCAD was developed to create the swimmer design, while computational fluid dynamics simulations using OpenFOAM were employed to calculate the propulsive force produced by the swimmer. Furthermore, an experimental approach is proposed and demonstrated to validate the model. The results show good agreement between simulations and experiments, indicating that the model could be used to develop an automatic geometry optimization pipeline for rotating swimmers.
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- PAR ID:
- 10552105
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-5851-3
- Page Range / eLocation ID:
- 3779 to 3784
- Subject(s) / Keyword(s):
- Robotics magnetic CFD
- Format(s):
- Medium: X
- Location:
- Bari, Italy
- Sponsoring Org:
- National Science Foundation
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