Orbital Control for Swimming in Underwater Snake Robots using Energy-Shaping and Consensus Control

Mads Erlend Bøe Lysø, Elena Panteley, Kristin Y. Pettersen, Jan Tommy Gravdahl

Abstract: In this paper, we present a controller for stabilizing and synchronizing a set of phase-shifted oscillations in a system of n double integrators. The motivating application is the control of swimming locomotion in an underwater snake robot. The oscillations are stabilized to a desired amplitude and frequency, and synchronized to achieve a desired phase shift between each oscillator. The result is a controller which stabilizes the desired gait while avoiding the undesirable transient behavior (colloquially known as “catching-up”-effects) associated with the tracking-based methods which are currently prevalent in the field. The controller is based on energy-shaping control and consensus control, and it is shown to render the desired orbit almost globally asymptotically stable. The emergence and stability of the desired behavior is demonstrated in a simulation study.