Monterey Bay Aquarium Research Institute
MBARI AUVs
Mapping vehicle specifications
auv interior
Larger version
Interior of the mapping AUV, with components called out.
Image © MBARI 2006		 vehicle design
Larger version
CAD drawing of the batteries, sensors, and computers assembled in the interior (top), surrounded with syntactic foam for flotation (middle), and encased in the plastic outer farings (bottom).
Image © MBARI 2006

General specifications for the Mapping AUV

  • Dorado-class vehicle
  • Size: 54 cm (21") diameter, 524 cm (17') length
  • Mass: 1018 kg (2240 lb) wet, 636 kg (1400lb) dry
  • Depth: routine operations to 1500 m, rated to 6000 m
  • Typical speed: 3 knots
  • Range: 55-85 km depending on sonar load
  • Endurance: 8.5 hours at 3 knots
  • Turning diameter: <20 m
  • Maximum climb/dive rate: > 30 m/minute
  • Operable: MBARI R/V Zephyr and R/V Western Flyer, and from blue water UNOLS vessels.

Instrumentation

  • Reson 200 kHz Multibeam Sonar
    flat receive array (model 7125)
    0.94 degree by 0.94 degree beams
    256 beams across a 150 degree swath
  • Edgetech FS-AU Sonar Package
    110 kHz chirp sidescan
    410 kHz chirp sidescan
    2-16 kHz chirp subbottom profiler
    >> More about the sonars
  • Sea-Bird SBE-49 FastCat CTD
  • Paroscientific pressure sensors, accuracy 0.005% of full scale
    • UCB7000 (0-7000 m depth range; 35 cm accuracy)
    UCB2000 (0-2000 m depth range; 10 cm accuracy)
receive ring
Multibeam receive ring, viewed from aft.
Image © MBARI 2005

Navigation

  • Kearfott SeaDevil inertial navigation system (INS): provides both vehicle navigation and attitude data
    dot24 cm ring laser gyro
    dotRDI 300 kHz doppler velocity log (DVL):
    velocity over bottom aids INS navigation when AUV is at an altitude less than 130 m
    dotKalman filter integrates gyro, accelerometer, DVL, and other navigation sensor data
    Position accuracy is 0.05% DT CEPR (distance traveled, circular error probability)
    dotHeading accuracy is 0.1o
    dotRoll and pitch accuracy is 0.025o
  • Surface-aided navigation: USBL fixes transmitted to vehicle from vessel using acoustic modem during descents on dives deeper than 200 m
  • Ashtech GPS when at surface
    >> More about navigation of the vehicle
Kearfott SeaDevil
Kearfott INS/DVL/GPS SeaDevil
Image © MBARI 2005

Power options

  • 5 kWhr Eagle-Pitcher secondary cells in a 1 atmosphere glass housing
  • 3 x 2 kWhr lithium-polymer pressure-tolerant batteries

Propulsion

  • MBARI-patented propulsion system
    Brushless DC motor and gear box
    dotDouble-gimballed ring-wing duct moves vertically for elevator, and horizontally for rudder
    Propeller moves with the duct
    52 Newtons (12 lbf) of thrust at 300 rpm
tailcone
Tailcone of the AUV
Image © MBARI 2005

Surface communications

  • Freewave RF modem, 57.6 kbps
  • Iridium phone
  • Radio Direction finder (RDF)

Submerged communications

  • Sonardyne Fusion USBL MF, 19 kHz down, 27 kHz up
  • 8-15 kHz Benthos acoustic modem

Deployment and recovery

  • Single vertical lift point
  • Front tow hook
  • Deployed with custom lift assembly or standard ship's crane
    >> More about deployment strategies for the vehicle

Safety

  • Slight positive buoyancy (~8 lbs buoyant)
  • Emergency 10 kg drop weight with internal and remote acoustic trigger
  • Homerpro acoustic beacon, RDF, strobe light
  • When on the surface, Iridium calls home to give a position

Next: Deployment

Last updated: Jan. 03, 2008