  We have built an information engine that can transport a bead in a desired
direction by using favorable fluctuations from the thermal bath. However, in
its original formulation, the information engine generates a fluctuating
velocity and cannot control the position of the bead. Here, we introduce a
feedback algorithm that can control the bead's position, to follow a desired
trajectory. The bead can track the path if the maximum desired velocity is
below the engine's maximum average velocity. Measuring the range of frequency
that the feedback algorithm can track, we find a bandwidth that is slightly
lower than the corner frequency of the bead in the trap.
