Automated Control of a Fleet of Slocum Gliders Within an Operational Coastal

Observatory

Rutgers University: E.L. Creed, J. Kerfoot, C. Mudgal, S.M. Glenn, O. Schofield

Webb Research Corporation: C. Jones, D.C. Webb

Dinkum Software: T. Campbell

WETLabs, Inc.: M. Twardowski

Mote Marine Laboratory: G. Kirkpatrick, J. Hillier

Development of Slocum Gliders Funded By:

Office of Naval Research

State of New Jersey

NOAA EcoHab Program

National Science Foundation - Biological

Why Gliders?

Until now data collection has been centered around short bursts of intensive sampling covering very small spatial areas

Gliders are beginning to provide continuous datacollection over long time periods (weeks) with littlehuman intervention making data acquisition:

1) more efficient2) less expensive3) more complete spatially and temporally

Goal

Develop an intelligent fleet of Slocum Gliders that will provide maps of the physics and bio-optics of coastal waterways

Goal divided into three areas:

1) Develop intelligent software to automatically control the Gliders

2) Develop miniaturized physical and bio-optical sensors to integrate into the Gliders

3) Perform both long duration Gliderflights and multiple Glider flights

Length: 1.5 mWeight: 52 kg

Hull Diameter: 21.3 cm

Slocum Electric Glider

Slocum Electric Glider

Glider Communication

Communication between the Glider and the Shore Command Center can be done in three ways:

1) FreeWave modems for local, high speed communication

Line of Sight RF (928MHz)

2) Iridium for bi-directional, long distance communications

3) ARGOS as a recovery beacon

Glider Operation Facts

Average deployment duration is 25 days and 600 km

Moves in a saw-toothed trajectory

Average forward speed of 1 kilometer/hour

Depth range 4-200 meters

Navigation done using GPS, dead reckoning and the altimeter

Deployment/recovery from small vessels of opportunity by one or two people

Glider Progress in Last Year

1) Software

2) Sensor Integration

3) Glider Flights

Control Center Software

A Mission Control Center is under constructionto guide the fleet of Gliders in their data collection

Implementation of the Mission Control Center is based on Agent Oriented Programming which is used by NASA in their exploring rovers

Control Center Software Desired Features

1) Must be a flexible, autonomous and responsive tool 2) Able to communicate with multiple gliders

simultaneously as well as external datasources such as CODAR, satellites

3) Able to process incoming data from all sources and determine if significant physical or bio-optical features are present

4) Able to change current mission if incoming dataindicates a change should be made

5) Able to notify researchers of the current statusof the mission

Glider Control Software Flow Chart

Y/N

18-Sep-2003 09:00:03

Glider Mission Tracking

Glider Progress in Last Year

1) Software

2) Sensor Integration

3) Glider Flights

Science Packages Integrated into Gliders

HydroScat 2

Breve Buster

SAM (Scattering Attenuation Meter)

HydroScat 2

HS2: measures optical backscatter at 2 wavelengths, Bb676 (red) and Bb470 (blue)

measures fluorescence at Bb676

Breve Buster

Breve Buster:a hyper-spectral spectrophotometerdetects red tide by measuring hyper-spectralabsorption

Scattering Attenuation Meter (SAM)

Measures backscatter (bb at 532nm), attenuation (c at 650nm), broadband side scattering (bs) and chlorophyll fluorescence (fl)

FL-LSS BB3

SAM

Glider Progress in Last Year

1) Software

2) Sensor Integration

3) Glider Flights

Missions Flown This Year

Where Duration Data Collected

Gulf of Mexico daily (January 13-16, 2003) CTD, HS2Gulf of Mexico daily (January 13-16, 2003) CTDLEO15 6 hours (May 5, 2003) CTDLEO15 7 hours (May 7, 2003) CTDLEO15 28 hours (May 14-15,2003) CTDLEO15 3 hours (May 20, 2003) CTD, Breve BusterLEO15 52 hours (July 15-17, 2003)CTDBoat Basin (Tuckerton) 47 hours (July 23-25, 2003) CTD, SAMLEO15 360 hours (Aug. 5-20, 2003)CTDCBLAST (Martha’s Vineyard) 70 hours (Aug 18-21, 2003) CTDBuzzard’s Bay 4 hours (Aug 18, 2003) CTD, SAMBuzzard’s Bay 7 hours (Aug 19, 2003) CTD, SAMLEO15 greater than 15 days CTD, HS2Gulf of Mexico 2 weeks CTD, Breve Buster

Gulf of Mexico January 15, 2003

Breve Buster Data

Data collected during the first in-water deployments of the Optical Phytoplankton Discriminator (OPD) at the Rutgers University Field Station, Tuckerton, New Jersey, May 20, 2003. Particulate absorbance spectra collected by the OPD were compared to the standard spectrum of the target species Karenia brevis, the Florida red tide dinoflagellate. Similarity index at or below 0.5 indicate that a very low proportion of the phytoplankton biomass is contributed by the target species. Inset shows the vertical cross-section of the Slocum Glider transect carrying the OPD.

Breve Buster Data – May 20, 2003

15 Day Deployment at LEO-15

August 5-20, 2003

Distance covered: 413.5km

Avg. Speed: 1.15km/hr

Communication: FreeWave and Iridium

3 Day Deployment off of Martha’s Vineyard

August 18-21, 2003

Distance covered: 21nm

Avg. Speed: 0.45km/hr

Communication: Iridium

7 hour Buzzard’s Bay Deployment

August 19, 2003

Conclusions

1) Gliders provide scientists with continuous and spatially extensive data2) Data can be automatically downloaded, processedand posted to the web3) 3 sensors have been successfully miniaturized and integrated into Gliders4) Multiple Gliders can be flown simultaneouslyin one area5) Single Gliders can be flown simultaneously in multiple areas6) Bi-directional communication with Gliders issuccessful via both Iridium and R/F modem

Future Plans

Software: Continued implementation of the agent software

Field Work: Continued long-term Glider deployments are planned for the New York Bight Apex to observe the interaction of the Hudson River plume with the stratified continental shelf waters

Breve Buster flights in Gulf of Mexico later this year to study red tides

Instrumentation: 1) Miniaturization and installation of upward and downward looking ADCPs

http://marine.rutgers.edu/cool

Glider