1.0 INTRODUCTION: HUGO is an ocean bottom observatory open for use by all
marine scientists within the hardware limitations of the observatory. HUGO
supplies electrical power and command capability to experiments on Loihi
seamount, and transmits data from experiments to shore at Honuapo,
Hawai'i. The main HUGO cable was emplaced on October 12, 1997, and HUGO
should be open for experiments in the summer of 1998. At its full
potential HUGO will have the capability to service more than 80
experiments. This guide is designed to aid potential experimenters in
proposing and designing experiments.
| Loihi seamount is the only known active submarine volcano in U.S. waters,
located about 20 miles off the southeast coast of the Island of Hawai'i (click on the figure to the right to see the location of Loihi).It suffered a large volcano-seismic event in July, 1996, and is likely to
still be erupting. Readers are directed to the Hawai'i Center for Volcanology's Loihi page for other information on Loihi. |  |
|
2.0 DEFINITIONS:
- 2.1 HUGO System: The HUGO System supplies the infrastructure for HUGO Experiments. The system includes hardware, power, phone lines, and
some data storage and dissemination services.
- 2.2 Main Cable: The AT&T SL Light cable connecting the shore station at Honuapo to the Junction Box at the summit of Loihi.
- 2.3 Junction Box: The seaward termination of the Main Cable. This is the main "patch panel" from which all Mux Nodes and experiments are connected.
- 2.4 Mux Nodes: Distribution centers that distribute power and collect data from experiments. There will be two levels of Mux Nodes; Level 1 Mux
Nodes connect directly to the Junction Box and represent the input to one
of the four data fibers; eight Level 2 Mux Nodes connect to one Level 1
Mux Node. Experiments are normally connected to Level 2 Mux Nodes. The
Junction Box contains an internal Level 1 Mux Node. Each Mux Node splits
the bandwidth by a factor of 8, thus there is a potential of 64
experiments per fiber, but overhead lowers this number to 49.
- 2.5 Experiments: An Experiment is a device that is nominally connected to a Level 2 Mux Node. An Experiment consumes up to 5 Watts of electrical
power supplied by HUGO, processes commands sent from the shore station,
and transmits 2048 32-bit data words per second to shore. These words
contain system information plus 8 to 24 bits of experiment data (see Table
2). High-rate or higher power experiments may be connected to Level 1 Mux
Nodes as long as ports are available.
- 2.6 Interface Module: A HUGO-supplied module to be incorporated into
experiments that supplies regulated power, clock, and commands to the
experiment, and processes data for transmission to shore.
- 2.7 Receiver Module: A PC-based circuit board that decodes HUGO
experiment data. HUGO supplies this module for testing use with Experimenters' computers.
- 2.8 Mux Cable: A Mux Cable connects Mux's to other Mux's or Mux's to the Junction Box.
- 2.9 Experiment Cable: An Experiment Cable connects an Experiment to a Mux Node. >
- 3.0 Experiment Command: An Experiment has the ability to process and act on requests from shore for non-routine actions for such as calibration,
leveling, gain changing, etc. Commands are passed to experiments either
as 8-bit words or serial RS-232. The experiment is responsible for acting
on commands. Up to 256 commands are possible, but some are reserved for
system use.
- 3.1 Shore Station: The Shore Station is the shore termination of the Main cable at Honuapo. The Shore Station initially consist of two 20' trailers
wired to the local power grid, and to telephone lines.
3.0 EXPERIMENTS:
- 3.1 Characteristics: The typical HUGO Experiment will consume up to 5
watts of electrical power and transmit 2048 Data Samples per second to
shore. HUGO Experiment hardware will be designed, constructed, and
tested by experimenters under guidelines presented here with the aid of
HUGO engineers. For compatibility reasons, HUGO will supply certain
components of experiments, including experiment cables, connectors,
power and data conditioning modules. Other standard modules, such as A/D
conversion units and command processors may also be purchased from HUGO.
HUGO Experiments will be emplaced by submersible or ROV, and may be
attached directly to a Mux Node, or be placed up to a mile away from the
nearest Mux Node, attached by cable.
- 3.2 Experiment data: Data rates from very low up to 2048 samples per second can be
accommodated without difficulty. See Table 2 below for sample formats.
HUGO experiment data will be the property of individual experimenters,
however, we expect that all experimenters will sign agreements allowing
use of their data by other experimenters with appropriate protections.
HUGO is a real-time system, and to fully utilize its potential, data from
all experiments should be available to others on a timely basis.
- 3.3 Physical package: The physical design of experiments must be such that
they can be emplaced by the PISCES V submersible run by the Hawai'i Undersea Research Lab (HURL) group at the University of Hawai'i. Otherwise, experimenters must make their own plans for emplacement, although HUGO will connect the experiment to the system. For installation by PISCES V, experiments should be no larger than 0.7 m on a side, with a weight in water of no more than 100 lb. Larger packages can be lowered to the bottom by wire and connected to HUGO
by submersible. The submersible will be able to deploy experiment
sub-units, such as external sensor packages, once the experiment is on
the bottom.
- 3.4 Mini-experiments: A Mini-Experiment Module is planned for groups with relatively simple needs who do not want, or cannot afford to construct a HUGO experiment. For mini-experiments, HUGO plans to supply experimenters with an electrical connection to HUGO supplying both power (±15 volts) and an analog data circuit (±10V) in a single connector. Up to eight
sub-experiment channels will be digitized at 256 samples/s and transmitted
to shore by the Mini-Experiment Module. Sub-experiments are intended for
student experiments.
4.0 EXPERIMENT DESIGN AND CONSTRUCTION TIMELINE: The following scenario is supplied as a possible model for how an experimenter might perform a HUGO Experiment.
- 4.1. Experiment conceptual design and scientific rationale. The experimenter plans an instrument for scientific measurement of some parameter on the ocean floor.
- 4.2. Contact HUGO. The experimenter contacts HUGO to be placed on the mailing list and to obtain the latest revision of this document. (HUGO@soest.hawaii.edu).
- 4.3. Write proposal. The experimenter writes a proposal to the appropriate funding agency to design, construct, emplace, and analyze data from the experiment. It may be beneficial to contact other HUGO experimenters at this point to write joint proposals and increase odds for funding. The HUGO Project will supply projected costs for HUGO parts, installation, and HUGO system overhead.
- 4.4. Equipment and scheduling. On successful funding, the Experimenter should immediately contact
the HUGO Office to plan parts procurement, submersible interface
information, and installation schedule. If location at a particular site
on Loihi is desired, considerable advance warning is needed to ensure that
system hardware is available in the area. A proposal for use of the
submersible will be submitted to HURL in conjunction with other HUGO
operations.
- 4.5. Instrument design and construction. HUGO engineers will be happy to make suggestions on Experiment design. Some basic guidelines are: no glass buoyancy, use foam; use titanium for pressure housings; keep power drain to a minimum; consider the possibility of recovering your package.
- 4.6. Testing. On completion, the instrument will be shipped to the University of Hawaii for testing at the HUGO System Test Bed. This test bed will emulate the HUGO system, and nominal operation of instruments at the Test Bed will ensure proper operation in HUGO.
- 4.7. Installation. The experiment will be carried to the bottom with the submersible, or lowered to the bottom from a surface ship, and subsequently connected to HUGO and moved to its proper location using the submersible. Data will be available as soon as power is turned on to the appropriate connector at the Mux Node. During emplacement, the
experimenter can monitor data in real-time through the receiver card in
his/her computer at the shore station.
- 4.8. Long-term data recording and dissemination. Each Experimenter will be supplied with data from his/her experiment. Experimenters will be able to view subsets of their data via Internet connections, and data will be stored on site and transmitted to experimenters in an appropriate format. Technology for data recording and distribution changes continuously, and the HUGO system will not settle on a particular storage medium and communication scheme until necessary. Experimenters will be charged an appropriate overhead for data collection, storage, and dissemination.
5.0 AVAILABILITY:
The HUGO System became operational in January, 1998, thus it is expected that the first set of experiments could be installed in September, 1998. Mux Nodes will be added to HUGO in appropriate locations on Loihi depending on the demand by funded experiments. HUGO is designed to operate for at least ten years.
| TABLE 1. DESIGN AND CONTRAINTS ON EXPERIMENTS |
| Weight: | Less than 100 lb. in water. |
| Size: | 0.7 m on a side or smaller (for the submersible to carry it to the bottom. |
| Materials (for permanent experiments):
Mechanical strength members:
Pressure vessels:
Buoyancy: |
titanium
titanium 6" id tubes
foam |
| Power Consumption: | nominal: less than 5 Watts continuous. |
| Power voltages at Experiment: (supplied by Interface Module): | nominal:
+5 volts TTL
±15 volts, analog supply |
| Clock Rate supplied (Interface Card): | 819.200 kBaud with sub-multiples |
| Data rate from Experiment:
connected to Level 1 Mux Node:
connected to Level 2 Mux Node: |
16,000 samples/s (655.360 kBaud)
2,048 samples/s (81.92 kBaud including 8 frame sync bits per word)
| Data word format:: | see Table 2 below |
| Components supplied by HUGO:
Interface Module:
Receiver Card:
connectors and cables: |
Approximate cost: $4,000
Approximate cost: $3,000
costs vary with experiment and length of cable | |
