  Magnetotactic bacteria (MTB) are of significant fundamental and practical
interest, especially for applications such as drug delivery and general-purpose
object manipulators and payload carriers. While magnetic and other modes of
control for individual MTB have been demonstrated, formation, motion and
control of MTB swarms are much less studied and understood. Here, we present a
torque dipole-based theoretical model for magnetic control of MTB swarms and
two methods for swarm formation, and provide experimental validation of the
proposed motion model. Model predictions are in good qualitative and
quantitative agreement with experiments and literature. Additionally, we were
able to determine the torque generated by Magnetospirillium gryphiswaldense
(MSR-1) MTB, and the value corresponds to the reported estimates reasonably
well.
