  The presence of obstacles is intuitively expected to hinder the diffusive
transport of micro-swimmers. However, for chiral micro-swimmers, a low density
of obstacles near a surface can enhance their diffusive behavior, due to the
rectification of the chiral motion by the obstacles. Here, we study numerically
the role that disorder plays in determining the transport dynamics of chiral
micro-swimmers on surfaces with obstacles. We consider different densities of
regularly spaced obstacles and distinct types of disorder: noise in the
dynamics of the micro-swimmer, quenched noise in the positions of the obstacles
as well as obstacle size polydispersity. We show that, depending on the type
and strength of the disorder, the presence of obstacles can either enhance or
hinder transport, and discuss implications for the control of active transport
in disordered media.
