Jorge Cortés
Professor
Cymer Corporation Endowed Chair
Coordinated rendezvous of underwater drifters in ocean
internal waves
M. Ouimet, J. Cortés
Proceedings of the IEEE Conference on Decision and
Control, Los Angeles, California, USA, 2014, pp. 6099-6104
Abstract
This paper considers a team of spatially distributed
drifters that move underwater under the influence of
an ocean internal wave. The team's objective is to
estimate the physical parameters that determine the
internal wave, use the then-known ocean dynamics to
rendezvous underwater, and finally return to the
surface as a cluster for easy retrieval. The focus
here is on the rendezvous task. From the structure
of the internal wave, the ocean's flowfield is
time-varying and spatially dependent on depth and
position along the wave propagation direction. The
drifters can control their depth by changing their
buoyancy and are otherwise subject to the horizontal
flowfield at their given depth. We consider two
different drifter dynamical models: a first-order
Lagrangian model, useful when the drifter's mass is
sufficiently small, and a second-order model, where
the drag force caused by the water accelerates the
drifter. We propose provably correct distributed
algorithms that rely on the drifters
opportunistically changing their depth so that the
ocean flowfield takes them in a desirable direction
to perform coordinated motion. The drifters
converge to the same depth and position along the
wave propagation direction asymptotically.
Simulations illustrate our results.
pdf  
Mechanical and Aerospace Engineering,
University of California, San Diego
9500 Gilman Dr,
La Jolla, California, 92093-0411
Ph: 1-858-822-7930
Fax: 1-858-822-3107
cortes at ucsd.edu
Skype id:
jorgilliyo