  Transport of a moving V-shaped barrier exposed to a bath of chiral active
particles is investigated in a two-dimensional channel. Due to the chirality of
active particles and the transversal asymmetry of the barrier position, active
particles can power and steer the directed transport of the barrier in the
longitudinal direction. The transport of the barrier is determined by the
chirality of active particles. The moving barrier and active particles move in
the opposite directions. The average velocity of the barrier is much larger
than that of active particles. There exist optimal parameters (the chirality,
the self-propulsion speed, the packing fraction, and the channel width) at
which the average velocity of the barrier takes its maximal value. In
particular, tailoring the geometry of the barrier and the active concentration
provides novel strategies to control the transport properties of micro-objects
or cargoes in an active medium.
