This thesis investigates how the swimming performance of untethered magnetic robots (UMRs) can be improved to overcome arterial blood flow. A laminar flow model is developed to simulate UMR behaviour, and multiple in vitro experiments are performed to validate it. The impact of friction and flow is studied, showing that hydrodynamic lubrication can significantly reduce wall contact and increase swimming speed.
To reach higher actuation frequencies, several mechanical solutions are explored. A multi-rotating permanent magnet (MRPM) is designed and tested, demonstrating a significant improvement in swimming speed compared to the single-magnet setup.
Results show a maximum speed of 82 mm/s, offering a promising step toward enabling UMR navigation against arterial flow.