A Numerical Study on the Locomotion of Spheroidal Microrobots Near Periodic Trapezoidal Walls

Magnetically driven microrobots have shown a broad application in medicine owing to their precise navigation and biocompatibility. Efficient locomotion of microrobots within confined and irregular fluidic environments is critical to their successful deployment in biomedical applications. However, systematic studies on the dynamic behavior of non-perfectly symmetric microrobots within complex boundary environments remain lacking. In this study, we establish a two-dimensional confined fluid domain model whose lower boundary is defined by a periodic trapezoidal function to mimic the corrugated morphology of biological conduits. We then investigate the locomotion of a spheroidal microrobot under three propulsion modes within this complex field. Our results reveal that pusher (β = −3) achieves the highest propulsion speed, allowing it most suitable for applications demanding high velocity. Furthermore, by introducing a gradient magnetic field, we demonstrate the potential of magnetic control to enhance microrobot stability. This study lays a theoretical foundation for the deployment of spheroidal microrobots in vivo environments and provides guidance for the design and control under complex physiological constraints.