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ABSTRACT: The Monterey Bay Aquarium Research Institute (MBARI) is developing a
high-resolution marine seismic refraction imaging system that can be
deployed and operated using a remotely operated vehicle. Conventional
marine seismic refraction methods typically use low-frequency sources
and widely-spaced seafloor receivers to image crustal-scale subsurface
structure. These systems often employ air-guns towed from a surface
vessel to produce acoustic signals ranging from 1-100Hz, and
ocean-bottom seismometers to record the refracted signals, resulting in
images on the scale of hundreds of kilometers with resolutions no better
than hundreds of meters. Images of subsurface structure at resolutions
on the order of meters requires closely-spaced, near-seafloor sources
and receivers capable of producing and recording higher-frequency
signals centered around 3kHz. This poster will describe the first phase
development of the High-Resolution Shallow Seismic Refraction Tomography
System at MBARI including the science drivers, the design approach and
trade-offs, and results from initial field tests conducted in the
Monterey Bay. The capability to image fine-scale subsurface structure
will augment ongoing research on hydrate deposits. Methane and the other
hydrocarbon gases trapped in hydrates are climate-impacting greenhouse
gases as well as potential energy sources. Therefore, research regarding
the formation, stability, volume, and structure of these globally common
deposits has considerable relevance today. High-resolution subsurface
imaging can impact many important marine geological topics such as
submarine faults, hydrothermal venting, and submarine volcanism. The
system combines ROV-mounted transmission of chirp acoustic signals with
a roughly 1-6 kHz sweep and an array of high-frequency ocean bottom
hydrophone (OBH) receivers. The configuration of closely spaced
receivers and a source pinging at tightly-spaced intervals provides the
opportunity to pick refracted arrival times and model the shallow
seismic velocity structure using 2D or 3D tomographic inversion
algorithms. The target experimental scale of subsurface sections ranges
from 100m across and 20m deep to 1km across and 200m deep. Given the
approximately 3 kHz center-frequency and a source shot spacing of less
than a meter, the best achievable resolution of subsurface structure
will be about 1 meter. Both the target scale and resolution is
ultimately determined by the receiver spacing used in the experiment.
Although the combination of chirp sonar technology, high frequency OBHs,
ROV operational capabilities, and tomographic inversion algorithms is
novel, all of the relevant technologies are mature and available.
Moreover, this capability will be readily exportable to oceanographic
institutions and programs with access to operational ROVs.
AGU Fall Meeting Abstracts. 11/2009; -1:1148.
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ABSTRACT: Autonomous Underwater Vehicles (AUVs) are an increasingly important tool for oceanographic research demonstrating their capabilities to sample the water column in depths far beyond what humans are capable of visiting, and doing so routinely and cost-effectively. However, control of these platforms to date has relied on fixed sequences for execution of pre-planned actions limiting their effectiveness for measuring dynamic and episodic ocean phenomenon. In this paper we present an agent architecture developed to overcome this limitation through on-board planning using Constraint- based Reasoning. Preliminary versions of the architecture have been integrated and tested in simulation and at sea.
Robotics and Automation, 2008. ICRA 2008. IEEE International Conference on; 06/2008
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ABSTRACT: The Monterey Bay Aquarium Research Institute (MBARI) has developed an autonomous seafloor mapping capability for high resolution mapping of the deep ocean seafloor. The MBARI Mapping AUV is a 21" diameter, Dorado class autonomous underwater vehicle (AUV) equipped with a 200 kHz multibeam sonar, 110 kHz and 410 kHz sidescan sonars, and a 2-16 kHz subbottom profiler. All components of the vehicle are rated to 6000 m depth. Using precise navigation and attitude data from an laser-ring-gyro-based inertial navigation system (INS) integrated with a Doppler velocity log sonar (DVL), the Mapping AUV can image the deep-ocean seafloor and shallow subsurface structure with much greater resolution than is possible with hull-mounted sonars. The system can also be operated in an ROV-mounted configuration, allowing near-bottom surveys in very restricted terrain. The Mapping AUV has conducted several autonomous surveys of Monterey Canyon and Smooth Ridge in Monterey Bay, and ROV-mounted surveys of five sites along the Monterey Canyon axis during 2005 and 2006. During June 2006, the Mapping AUV surveyed mounds and channel deposits in the Santa Monica Basin. The bathymetric surveys have achieved a vertical precision of 0.3 m; surveys from a 20 m altitude achieve sub-meter lateral resolution and surveys from 50-100 m altitudes achieve lateral resolutions less than 2 m. The subbottom profile data provides resolution of ~0.1 m with penetrations up to 50 m in soft sediments. The combination of high-resolution bathymetry with closely spaced subbottom profiles allow us to Additional Mapping AUV expeditions are planned for 2006, including surveys of Barclay submarine canyon and the summits of Davidson and Axial seamounts
OCEANS 2006; 10/2006
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ABSTRACT: The Monterey Bay Aquarium Research Institute (MBARI) has developed an autonomous underwater vehicle (AUV) for deep ocean seafloor mapping. The MBARI Mapping AUV is a 21" diameter, torpedo-shaped Dorado class vehicle equipped with a 200 kHz multibeam sonar, 110 kHz and 410 kHz chirp sidescan sonars, and a 2-16 kHz sweep chirp sub bottom profiler. The multibeam sonar incorporates a circular receive array conformal to the vehicle hull, providing 1 degree × 1 degree beam resolution over a 150 degree swath. Navigation and attitude data are provided by an inertial navigation system integrating a laser ring gyro, accelerometers, and a 300 kHz Doppler velocity log (DVL). The vehicle is tracked during missions using an ultra-short baseline navigation system. The vehicle will also include acoustic modem and long-baseline navigation capabilities. A central cylindrical pressure housing contains all of the mapping sonar electronics. The main vehicle control and acoustic communications electronics are housed in a separate pressure housing in the vehicle tail section. Propulsion and steering are provided by a tailcone including an articulating propeller. Li-ion or Li-polymer battery packs allow for a 12 hour mission duration. The assembled package is rated to 6000 m depth. The mapping payload is also designed for ROV mounting, enabling low altitude (< 20 m) high precision missions in topographically challenging sites. The Mapping AUV has now been operated in both autonomous and ROV modes in and around the upper Monterey Canyon, successfully collecting high-resolution multibeam bathymetry and subbottom profile data. Near bottom surveys of the canyon axis achieve bathymetric coverage with a lateral resolution of 1 m and a vertical precision of 0.3 m. The subbottom profiler images subsurface structure to depths of 60 m in soft sediments.
OCEANS, 2005. Proceedings of MTS/IEEE; 02/2005
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ABSTRACT: Engineers and scientists at the Monterey Bay Aquarium Research Institute (MBARI) have successfully developed instrumentation for performing laser Raman spectroscopy in the deep ocean. Laser Raman spectroscopy is a form of vibrational spectroscopy that is capable of performing rapid, nondestructive, in situ geochemical analyses. The Deep Ocean Raman In Situ Spectrometer (DORISS) is based on a laboratory model laser Raman spectrometer from Kaiser optical systems, Inc. The sample is interrogated by a 532 nm laser and the Raman backscattered radiation passes through a holographic grating and is recorded on a CCD camera. Laser Raman spectroscopy is capable of analyzing a variety of solid, liquid and gaseous species. Due to the strict requirements for positioning the laser focal point when analyzing opaque samples, a Precision Underwater Positioning (PUP) system was built to position the DORISS probe head with respect to the sample. PUP is capable of translating the DORISS probe head in 0.1 mm increments with 1 mm repeatability. DORISS and PUP are deployed by MBARI's remotely operated vehicles - ROVs Tiburon and Ventana - and are controlled by a scientist aboard the surface ship. DORISS and PUP have been deployed a number of times in Monterey Bay, the Gulf of California, and Hydrate Ridge, Oregon for testing and analyses of natural targets of interest. The development of smaller, second generation systems will allow DORISS and PUP to be carried on other deep submergence vehicles for use by the wider oceanographic community.
OCEANS '04. MTTS/IEEE TECHNO-OCEAN '04; 12/2004
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ABSTRACT: The Monterey Bay Aquarium Research Institute (MBARI) is developing an autonomous seafloor mapping capability for deep ocean science applications. The MBARI Mapping AUV is a 0.53 m (21 in) diameter, 5.1 m (16.7 ft) long, Dorado-class vehicle designed to carry four mapping sonars. The primary sensor is a 200 kHz multibeam sonar producing swath bathymetry and sidescan. In addition, the vehicle carries 100 kHz and 410 kHz chirp sidescan sonars, and a 2-16 kHz sweep chirp subbottom profiler. Navigation and attitude data are obtained from an inertial navigation system (INS) incorporating a ring laser gyro and a 300 kHz Doppler velocity log (DVL). The vehicle also includes acoustic modem, ultra-short baseline navigation, and long-baseline navigation systems. A single cylindrical pressure housing contains all of the mapping sonar electronics, and the main vehicle control and acoustic communications electronics are housed in a separate glass ball. The Mapping AUV is powered by three 2 kWhr Li-polymer batteries, providing an expected mission duration of 12 hours at a typical speed of 1.5 m/s. The assembled package is rated to 6000 m depth, allowing MBARI to conduct high-resolution mapping of the deep-ocean seafloor. Initial at-sea testing commenced in May 2004 using the subbottom profiler and 100 kHz sidescan. The sonar package will also be mountable on ROV Ventana, allowing surveys at altitudes < 10 m at topographically challenging sites. The MBARI Seafloor Mapping team is now working towards integration of the multibeam sonar and towards achieving regular operations during 2005.
OCEANS '04. MTTS/IEEE TECHNO-OCEAN '04; 12/2004
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ABSTRACT: Summary form only given. The Monterey Bay Aquarium Research Institute (MBARI), in conjunction with California Polytechnic Institute in San Luis Obispo and UCSB, have conducted two in a series of multi-parameter oceanographic surveys designed to measure coastal upwelling, frontal processes, and bioluminescence in the Monterey Bay. The surveys have consisted of one to two weeks of continuous, round the clock operations in August 2000 and August 2002, allowing repeat mapping of biological and physical features as well as synoptic mapping of bioluminescence at multiple points in the Bay. These surveys have utilized autonomous underwater vehicles, autonomous vertical profilers and moorings to achieve the necessary spatial and temporal scales and resolutions, as well as a variety of shipboard instruments and cast samplers to provide baseline data and quality control. We describe and motivate our survey design, as well as describe the instrument configuration of the REMUS and Dorado AUVs for this particular survey. We also present an overview of joint AUV/ship operations and data collected. In particular, we discuss the integration and present data from two unique instruments carried by the AUVs: a particle size analyzer for measuring suspended sediments in upwelling regions, and a bathyphotometer for measuring emitted light from plankton. We close with a discussion of the operational and scientific lessons we have learned through out intensive survey operations, and the integration of these surveys into a broader coastal observation and prediction system.
OCEANS 2003. Proceedings; 10/2003
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ABSTRACT: The Monterey Bay Aquarium Research Institute (MBARI) has developed and deployed a laser Raman spectrometer system (DORISS-Deep Ocean Raman In-Situ Spectrometer) for oceanic geo-chemical measurements of sea water specimens. Quality spectra have been obtained on standards carried to the seafloor. The next stage of this development involves the ability to obtain spectra from natural targets of interest in the deep ocean and to maximize signal return from the sample. To accomplish maximum signal return the DORISS probe head must be properly positioned and focused. In addition the probe head must be held steady for several minutes while spectra are being acquired. This is in contrast to laboratory work in which the sample is precisely positioned with respect to the probe head. This requirement has been the driver for a new device, the Precision Underwater Positioning system (PUP). The positioning system has strict requirements for motion about the target. The DORISS requires very exact and repeatable motions with positional accuracies in the <1 mm range over a large workspace. The device must also let the user see where they are focusing, be able to move without disturbing the base position, and to stay stable over a variety of terrains. In addition, the system must be adaptable to other vehicles. Another requirement is to return relative position from a known home position once the PUP is set in place. Moreover, the device has several operational constraints that impacted the design and operation of the system. This paper outlines the science drivers, the operational considerations, and the engineering trades that were made to build the first two stages of the PUP. The test results of this system are also included demonstrating the device's actual performance against the specifications. In conclusion the paper outlines the next tasks and the direction the program is taking to fulfill the complete precision underwater positioning system requirements.
OCEANS 2003. Proceedings; 10/2003
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J. G. Bellingham,
W. J. Kirkwood,
N. Tervalon,
E. Cokelet,
H. Thomas,
M. Sibenac,
D. Gashler,
R. McEwen, R. Henthorn,
F. Shane,
D. J. Osborn,
K. Johnson,
J. Overland,
P. Stein,
A. Bahlavouni,
D. Anderson
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ABSTRACT: An Autonomous Underwater Vehicle designed for operation at high
latitudes and under ice completed its first Arctic field tests from the
USCGC Healy in fall of 2001. The ALTEX AUV has been under development
since 1998, and is being created to provide: unprecedented endurance,
ability to navigate at high latitudes, a depth rating of 1500 to 4500
meters depending on payload, and the capability to relay data through
the ice to satellites via data buoys. The AUV's initial applications
are focused on tracking the warm Atlantic Layer inflow - the primary
source of seawater to the Arctic Ocean. Consequently the primary
payloads are twin pumped CTD systems. Oxygen and nitrate sensors
provide the ability to use NO as a tracer. An ice profiling sonar
allows the AUV to estimate the ice thickness in real-time and is
designed to generate high quality post-processed ice draft data
comparable to that collected through the SCICEX program. The
experiments in October aboard the USCGC Healy generated numerous water
column and under-ice data sets. Traditional ship-based CTD operations
were used to provide a comparison data set for AUV water column
measurements. The post-processed ice draft results show reasonable ice
profiles and have the potential, when combined with other science data
collected, to shed some additional light on upper water column processes
in ice-covered regions. Cruise results include: operating the AUV from
the USCGC Healy in the ice pack, demonstrating inertial navigation
system performance, obtaining oceanographic sections with the AUV,
obtaining ice draft measurements with an AUV born sonar, and testing the
data-buoy system. This work is supported by the National Science
Foundation under grant NSF-OPP 9910290. The Packard Foundation and the
Office of Naval Research have also provided support. The project was
initiated under the National Ocean Partnership Program under contract
N00014-98-1-0814.
AGU Fall Meeting Abstracts. 11/2002; -1:0282.
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ABSTRACT: The original Odyssey vehicle systems established a style of platform that has proven to be extremely versatile and useful for a variety of scientific missions. The Monterey Bay Aquarium Research Institute (MBARI) has carried forward the Odyssey design, now called Dorado. Dorado is a mid-sized vehicle in comparison to other AUV systems. Dorado vehicles are 0.5334 m (21") diameter, and are designed for deep water (4500 m) operation. The Dorado design improves upon the original Odyssey versatility by dividing the vehicle up into modular sections. Specific sections can then be built to carry out each type of mission. A Dorado vehicle can then consist of a nose section, one or several mission-specific midbodies, and a tail section. The main vehicle systems for propulsion, control, data handling, navigation, acoustic sub-systems, and most other standard functions are housed in the tail section. This paper introduces the history of the Dorado systems, and what has been accomplished to date. This paper further describes the various architectural concepts and operational results. Future planning is also discussed.
OCEANS '02 MTS/IEEE; 11/2002
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ABSTRACT: The harsh environment and limited resources available in the Arctic region make collection of most scientifically relevant data in the area difficult and/or expensive. The Monterey Bay Aquarium Research Institute (MBARI), along with other partners, has developed an autonomous underwater vehicle (AUV) specifically designed to withstand the difficult environment in the Arctic and capable of collecting a variety of scientific data. This tool has the potential to replace capabilities previously supported by the US Navy SCICEX cruises which used submarines for measuring and monitoring Arctic oceanographic properties. Scientific access to Navy submarines has been severely restricted over the last several years, with the future prospects for continued support uncertain. Ice draft data was one important piece of data historically collected by the submarines that MBARI's AUV now has the potential to provide. This ice draft data has particular value to climatologists and Arctic scientists who are striving to evaluate the impact of global climate on the thickness and extent of the Arctic ice sheet. This paper examines the ice draft data collected by the ALTEX AUV during its engineering test cruise in the Arctic in October 2001. A description of the experiments and the general performance of the vehicle are presented along with the scientific instrumentation layout of the AUV. Further, the modifications made to the ASL Environmental Sciences Ice Profiler™ instrument to support vehicle operations in real-time are described. The use of this real-time data to drive vehicle decision making during missions is addressed as well. The data acquisition and processing techniques used to determine ice draft are then outlined, followed by samples of the ice draft data itself and estimates of its accuracy and repeatability. The conclusion include lessons learned and future plans for the ice profiling science payload.
OCEANS '02 MTS/IEEE; 11/2002
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ABSTRACT: The MBARI Ocean Observing System (MOOS) will consist of networked
observation platforms and sensors deployed over a wide geographic area,
distributed throughout the oceanic water column. The network will
utilize a variety of communication links, including optical fiber,
microwave, packet radio, satellite, and acoustic, resulting in diversity
of throughput, latency, and intermittence throughout the network. The
network membership will be highly dynamic and unpredictable, as links go
"up" and "down", and devices are added to and removed from the network.
The sensors themselves will include a wide range of off-the-shelf
instruments as will as novel devices developed at MBARI and elsewhere;
sensor interface protocols will thus be very diverse, as there are
currently no widely recognized standards. These aspects of the ocean
observing system network present challenging software engineering
problems. The authors review available "smart network" software
technologies that address these problems, and evaluate their feasibility
for their system. Addressing the diversity of sensors and protocols,
they describe a device called a sensor puck, that could provide a
universal interface between any sensor and the network, and that enables
spontaneous configuration and operation when the sensor is plugged into
the network
OCEANS, 2001. MTS/IEEE Conference and Exhibition; 02/2001
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Anesthesia & Analgesia 10/1996; 83(3):665. · 3.29 Impact Factor
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Proc. OCEANS 2006;
