Routing strategies for underwater gliders

Russ E. Davis, Naomi Ehrich Leonard, David M. Fratantoni

Research output: Contribution to journalArticle

39 Citations (Scopus)

Abstract

Gliders are autonomous underwater vehicles that achieve long operating range by moving at speeds comparable to those of, or slower than, typical ocean currents. This paper addresses routing gliders to rapidly reach a specified waypoint or to maximize the ability to map a measured field, both in the presence of significant currents. For rapid transit in a frozen velocity field, direct minimization of travel time provides a trajectory "ray" equation. A simpler routing algorithm that requires less information is also discussed. Two approaches are developed to maximize the mapping ability, as measured by objective mapping error, of arrays of vehicles. In order to produce data sets that are readily interpretable, both approaches focus sampling near predetermined "ideal tracks" by measuring mapping skill only on those tracks, which are laid out with overall mapping skill in mind. One approach directly selects each vehicle's headings to maximize instantaneous mapping skill integrated over the entire array. Because mapping skill decreases when measurements are clustered, this method automatically coordinates glider arrays to maintain spacing. A simpler method that relies on manual control for array coordination employs a first-order control loop to balance staying close to the ideal track and maintaining vehicle speed to maximize mapping skill. While the various techniques discussed help in dealing with the slow speed of gliders, nothing can keep performance from being degraded when current speeds are comparable to vehicle speed. This suggests that glider utility could be greatly enhanced by the ability to operate high speeds for short periods when currents are strong.

Original languageEnglish (US)
Pages (from-to)173-187
Number of pages15
JournalDeep-Sea Research Part II: Topical Studies in Oceanography
Volume56
Issue number3-5
DOIs
StatePublished - Feb 1 2009

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routing
autonomous underwater vehicle
travel time
speed
spacing
trajectory
vehicle
sampling

All Science Journal Classification (ASJC) codes

  • Oceanography

Cite this

Davis, Russ E. ; Leonard, Naomi Ehrich ; Fratantoni, David M. / Routing strategies for underwater gliders. In: Deep-Sea Research Part II: Topical Studies in Oceanography. 2009 ; Vol. 56, No. 3-5. pp. 173-187.
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Routing strategies for underwater gliders. / Davis, Russ E.; Leonard, Naomi Ehrich; Fratantoni, David M.

In: Deep-Sea Research Part II: Topical Studies in Oceanography, Vol. 56, No. 3-5, 01.02.2009, p. 173-187.

Research output: Contribution to journalArticle

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