Numerical modeling of bacteria propelled micromotors

We describe a numerical model for simulating micro-objects immersed in a bath of self-propelled organisms. By using simplified models for swimming cells (2 beads rigidly connected and subject to a self-propelling force) and taking into account various interaction terms (collisions, hydrodynamics), we simulate different shaped devices immersed in the bacterial bath. Considering rotating cog-wheels and translating shuttles we demonstrate the emergence of unidirectional motions, whose efficiency depends on the object shape as well as on bacterial properties. The role of tumbling mechanism and hydrodynamic interactions is analyzed. (C) 2011 Elsevier B.V. All rights reserved.