The dynamics of a planar beating micro-swimmer constructed using functional fluid

Abstract

The dynamics of a flexible micro-swimmer that contains superparamagnetic beads of different diameter in an oscillating field is studied experimentally. Two types of artificial swimmers are fabricated to determine the flexing characteristics. The effect of key parameters that dominate the motion of the swimmer is determined. The flexibility initially increases linearly with the frequency and reaches a maximum value at a specific frequency. The field intensity has no significant effect on the flexibility when the swimmer is subjected to a higher oscillating frequency. The instantaneous speed of the swimmer increases almost linearly with the flexibility and reaches a maximum value for a swimmer with a specific geometry. On the other hand, the amplitude of the oscillation has a significant effect on swimming effectiveness. The swimmer achieves a maximum instantaneous speed of 1.78 μm/s to 3.16 μm/s when the oscillating amplitude reaches 3.7–4.2 μm. A flexible swimmer with a moderately high amplitude of oscillation generates effective propulsion in an environment with a low Reynolds number of 2.5×10−6–4.5×10−5.