Moving mass control for underwater vehicles

We present two reduced-dimensional, noncanonical Hamiltonian models for a neutrally buoyant underwater vehicle coupled to an internal moving mass. It is expected that these models will be useful in designing nonlinear control laws for underwater gliders as well as for spacecraft, atmospheric re-entry vehicles, and other vehicles which use internal moving mass actuators. To illustrate, we investigate stability of a steady underwater vehicle motion using potential shaping feedback with a moving mass actuator.