In-channel experiments on vertical swimming with bacteria-like robots

Bio-inspired micro-robots are of great importance as to implement versatile microsystems for a variety of in vivo and in vitro applications in medicine and biology. Accurate models are necessary to understand the swimming and rigidbody dynamics of such systems. In this study, a series of experiments are conducted with a two-link cm-scale bioinspired robot moving vertically without a tether, in siliconefilled narrow cylindrical glass channels. Swimming velocities are obtained for a set of varying tail and wave geometries, and employed to validate a resistive force theory (RFT) model using modified resistance coefficients based on measured forward velocity and body rotation rates

Improved kinematic models for two-link helical micro/nano-swimmers

Accurate prediction of the three-dimensional trajectories of micro/nano-swimmers is a key element as to achieve high precision motion control in therapeutic applications. Rigid-body kinematics of such robotic systems is dominated by viscous forces. The induced flow field around a two-link swimmer is investigated with a validated computational fluid dynamics (CFD) model. Force-free-swimming constraints are employed in order to simulate motion of bacteria-like swimmers in viscous medium. The fluid resistance exerted on the body of the swimmer is quantified by an improved resistance matrix, which is embedded in a validated resistive force theory (RFT) model, based on complex-impedance approach. Parametric studies confirmed that the hydrodynamic interaction between body and tail are of great importance in predicting the trajectories for such systems