Biomimetic artificial cilia with three-dimensional motion driven by magnetic fields

Inspired by natural cilia, we developed magnetically actuated artificial cilia capable of controlled three-dimensional motion. The key innovation lies in concentrating hard magnetic particles at the tip of a silicon pillar, enabling asymmetric effective and recovery strokes under a constant rotational magnetic field. By magnetizing the pillar at 45° to the ground, we achieved complex three-dimensional movements that closely mimic biological ciliary motion. Our developed simulation system reproduced individual pillar trajectories in static conditions, showing consistency with experimental results in the range without snapping, a phenomenon characterized by the sudden release of twist-induced stress. Furthermore, we demonstrated metachronal wave-like motion in pillar arrays. These arrays exhibited both transport capabilities, successfully moving a 10 mg object, and locomotion functions. The combination of precise motion control, predictive modeling, and demonstrated functionality suggests promising applications in microfluidic manipulation and biomedical devices.