  Micron-sized self-propelled (active) particles can be considered as model
systems for characterizing more complex biological organisms like swimming
bacteria or motile cells. We produce asymmetric microswimmers by soft
lithography and study their circular motion on a substrate and near channel
boundaries. Our experimental observations are in full agreement with a theory
of Brownian dynamics for asymmetric self-propelled particles, which couples
their translational and orientational motion.
