  We use numerical simulations to study the motion of a large asymmetric tracer
immersed in a low density suspension of self-propelled nanoparticles in two
dimensions. Specifically, we analyze how the curvature of the tracer affects
its translational and rotational motion in an active environment. We find that
even very small amounts of curvature are sufficient for the active bath to
impart directed motion to the tracer which results in its effective activation.
We propose simple scaling arguments to characterize this induced activity in
terms of the curvature of the tracer and the strength of the self-propelling
force. Our results suggest new ways of controlling the transport properties of
passive tracers in an active medium by carefully tailoring their geometry.
