Propulsive energy harvesting by a fishlike vehicle in a vortex flow: Computational modeling and control

Using a model rooted in Hamiltonian mechanics, we consider the self-propulsion of a deformable planar hydrofoil in an ideal fluid in the presence of ambient vorticity, and investigate the mechanism whereby the hydrofoil can harvest energy from the surrounding flow in order to improve its own energy efficiency. We demonstrate, in particular, that energy harvesting can be achieved via closed-loop control without explicitly incorporating an assessment of the fluid velocity field into the feedback signal.