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• Combine regional directories into

an international directory.

• Conduct regional meetings of work

ing groups with agency sponsorship.

Mr. Yorihisa Suwa, of Japan Radio, “Opportunities for International Cooppresented his company's integrated eration in Swath Sonar Processing.” At system called “Total NAVIGATOR this writing 82 swath bathymetry sysIII," which uses electronic charts to tems are being used world wide. The add coastal and channel navigation to United States (29) and Japan (19) its navigation system. Displayed infor- maintain the bulk of the systems, with mation includes:

Norway (8), Canada (5), U.S.S.R. (5),

England (3), Germany (3), The • Navigational data - graphic coast Netherlands (3), France (2), Australia

line, depth, boundaries, dangerous (1), India (1), Korea (1), and Spain (1). zones, markers, scheduled route, ship in the United States, recognizing the track, other ship's track from auto- complex problems involved in intematic radar plotting aids (ARPA) grating information from many different

systems, the Defense Hydrographic • Numeric data - time, ship's posi- Initiative was developed to deal with

tion, speed, total distance, course to coordination among the Defense steer, bearing and time to way point, Mapping Agency, the Oceanographer cross track error, from meters- of the Navy, and NOAA. The initiative heading, rudder angle, turn rate treats three primary areas:

• Conduct international meetings of

representatives of regional working groups with sponsorship assistance from agencies and

sonar manufacturers.

• Exchange processing software for

swath bathymetry and imagery among working group members.

• Exchange swath sonar ship tracks

and data through existing organizations.

Weather data - wind direction and 1. Standardization of hydrographic/ Dr. Akira Asada, of JHD, presented velocity, atmospheric pressure, rela- bathymetric data collection, a paper titled “New Bathymetric Surtive humidity, air temperature, water processing/evaluation, archiving and veying and Processing System Based temperature

analysis/integration.

on Sea Beam 2000.” This was a discus

sion of the system on their new survey • Hull motions - pitch, roll, metacen- 2. Product and service identification ship MEIYO, which begin surveying in

tric height (GM), draft and trim, and definition and implementation March 1991. Navigation generally uses propeller slip ratio

of the necessary support process.

MX440GPS, MX4810GPS, and R-R

LORAN-C in various order of priority • Engine data - propeller revolutions, 3. Coordination of research and devel- depending on quality of the returns.

propeller pitch, shaft horsepower, opment (R&D) initiatives among This permits preparation of (1) a depth torque, main engine (M/E) loading, academia, private industry, allied contour chart along the track, (2) a turbocharger revolution, M/E start hydrographic offices, and interna- track chart, and (3) a sounding chart air pressure, M/E temperature tional organizations as appropriate. incorporating the navigation with the

output of the Sea Beam system. JHD The system allows the user to make an Implied is the development of digital has modified the existing processing electronic chart from a paper chart, products such as a Master Seafloor software and developed new programs incorporating a computer with a dig- Digital Database (MSDDB) to include: to improve and extend the processing itizer. One electronic chart may have topographic properties, man-made capability. Eventually they would like five mark (buoys, etc.) and seven line points, line and area features, gravity, to have all processing in real time on (coast line, depth contours, etc.) types magnetics, geoacoustic properties, and ship board. The processing programs at one time. One megabyte on a floppy acoustic bottom properties. Dr. Tyce discussed in detail are as follows: disk holds a maximum of 15 electronic proposes the creation of an Internacharts.

tional Working Group that would take • Position-Fix Correction: This prothe following actions:

gram is designed to remove spike TECHNICAL REPORTS ON

errors in the fixes, to smooth meanMULTI-BEAM TECHNOLOGY • Create regional directories of orga- derings produced by instability of

nizations and individuals involved the fixes, and to process differences Dr. Robert Tyce of the Ocean in swath sonar processing: Organi- in level that result from data from Mapping Development Center of the zation, Name, Computer Type,

combinations of GPS satellites. University of Rhode Island discussed Address, Phone Numbers, and

Computer Mail Address.

94

• JMSA Uniform Format: The use of Square (RMS) Error Calculation, Roll- (usually several hundred); (3) estimates

this program converts the data from Bias Assessment, Tidal Correction, new biases based on old estimates and the multi-beam system to a unified Sound Velocity Path (SVP) Recalcula- partial derivatives of the model depth system. Software is available for Seation, and Sounding Accuracy Assess- function; (4) computes new models Beam 2000, Sea Beam, HS-10, ment. Dr. Asada pointed out that the based on new error angle estimates; HS-200, and Hydrosweep.

Sea Beam system uses a mean speed of and (5) continues iterations until the

sound assumption. This would produce sum of squared differences ceases to • Erroneous Data Elimination: This errors of just over 1% for depths shal- decrease ("total number of iterations

program identifies and “corrects" lower than 4,000 meters and worse than is usually 5 to 12"). Results to date spikes and anomalous readings based that at greater depths. He presented a indicate that the system can detect pitch on integration of 100 shots looking series of examples showing how the and roll biases “accurately and repeatfore and aft as well as right and left Ray Curve, SVP, and Surface Layer edly." Similar results for yaw have not of the shot point, assuming that no Refraction corrections are influenced been achieved, due to, for example, th topographic feature has only one by the mean speed of sound assump- ship’s gyro input not sufficiently accuspike datum. The program is designed tion. Finally, examples were shown of rate and tests need to be run on steeper to allow for complex topography the survey of the area of Mikura Sea- slopes. near seamounts, scarps, trenches, mount comparing real-time contour “Sea Beam System of the Ocean etc. At present, processing of maps with postcruise processing (2 days). Research Institute, University of Tokyo” 100-shot points takes 18 seconds. The real-time map is useful in identify- was the paper given by Dr. Kensaku One segment of a survey line, which ing areas of poor sounding for resurvey Tamaki. Sea Beam mapping cruises on corresponds to 150 MB, takes about before leaving the area. The combina- the HAKUHO-MARU have been made a half day for processing.

tion of the existing Sea Beam 2000 to the Nankai Trough (1989), the Japan

system with the error check and correc- Trench (1990), and the Manus Basin • Contour Processing: This program tion software developed by JHD is (1991). Future cruises are planned for

translates the geographic positions providing extremely high quality bathy- the Ayu Trough (1992), Kuril Trench to the longitude of the beam posi- metric information with a low failure (1992), and the Mid-Indian Ridge tions as the heading of the vessel rate.

(1993). The presentation was mainly usually differs from the direction on Continuing with the theme of error on the data handling systems. Data an X-Y chart. This leads to inaccu- correction, Dr. Thomas Stepka of processing was managed by a fourrate cross track distances on a NOAA gave a paper on “An Auto- channel serial (RS232-C, 9600 bps) Mercator projection.

mated Method of Detecting Errors in interface inside a DG S/140 minicom

Beam Pointing Angles in Swath Sonar puter. The real-time mapping system is • Digital Color Printer Application: Arrays." The beam angle error is a operated by a Yokogawa-Hewlett

Programs written for the Pictography function of the deviation about a ship’s Packard 350 SRX workstation with 2000 color thermal printer with a pitch, roll, and yaw axes. Convention- 24 MB used for processing. Data from capacity of 2048x2560 pixels permit ally, a “patch test” is run over a test the Magnavox Series 5000 used for shipquality mesh map presentations of area and the results are plotted by hand. board data (navigation, etc.) and from the processed soundings. With this However, the method requires a smooth the Sea Beam system are stored in a software, three-dimensional image bottom and is very labor intensive with 300-MB hard disk. All data files are processing, magnitude mapping of marginal statistical significance due to accessible from shipboard workstations sea bottom inclination, and direc- the small number of points used. NOAA

the small number of points used. NOAA via an optic fiber cable Ethernet LAN. tion mapping ofsea bottom inclina- has awarded a contract to the TAU Formats and byte addresses for the tion can be produced in color coded Corporation to develop an automated various parameters are given in several

patch test analysis system. The system detailed tables.

was delivered in August 1991. The algo- Dr. Katsutoki Matsumoto, of the Other programs listed but not discussed rithm developed (1) selects an initial Metal Mining Agency of Japan, preinclude GPS Differential Postprocess- estimate of pitch, roll, and yaw devia- sented for his colleagues Kouhei Maeda, ing and Track Chart Processing. For tions and computes the depth for each Madao Saito, and Nobuyuki Murayama the Sea Beam 2000 system programs model; (2) computes the sum of the all of the Deep Ocean Resources Develinclude Contour Processing Time- squared differences between models atopment Co. Ltd., a paper titled “EquipSequential, Sounding Chart, Root Mean

every sounding in the user-defined area ping R/V HAKUREI-MARU No. 2

mesh maps.

with MBES and Test of MBES. MBES systems proved a successful way to as well as nonrecognition of established refers to Multi-Beam Echo Sounder, interpret structural lineations and other features. In general, short-wavelength which was the Krupp-Atlas Hydrosweep. fine-scale features.

topographic features clearly present in The HAKUREI-MARU is designed Industry representative Mr. Sea Beam are reduced in the HS-10 and equipped for exploration for min- Hideharu Morimatsu of Furuno Elec- reconstructions. Some of the differeral resources on the deep seabed. Thus tric Co., Ltd. presented “Development ences may be explained by differences the multi- and narrow-beam systems of Multiple Narrow Beam Echo in the gate settings with cross track were tested with respect to their suita- Sounders for Shallower Waters.” Two “noise” responsible for artifacts in the bility for ocean mining surveys. For systems, the HS-200 II (150 kHz, max

HS-10 system. surveys deeper than 5,500 meters, the imum depth 600 meters) and the The final presentation was given by ship was modified to reduce under- HS-500 II (500 kHz, maximum depth

HS-500 II (500 kHz, maximum depth RADM Andreasen, substituting for water noise. Improvements were to 50 meters), and the attendant software CAPT John C. Albright of NOAA. The install a high skew propeller and to add package “Sea Map PC” were discussed. paper, “Use of Differential GPS at the stern tunnel fins, auxiliaries, and pumps The systems have been used in several National Ocean Service," described the in the engine room and pipe lines were practical situations including not only efforts to develop and test a system for made vibration-proof in support. This primary bathymetric surveying but in vessel positioning that improves the reduced the noise level 12 dB at 12 knots confirming locations of objects placed positions available for either the Stanand 26dB at8 knots. Tests in the spring on the seafloor. In this example, an dard Position Service (SPS) or the of 1991 in the Izu-Ogasawara (Bonin) array of artificial fish shelters, each a Precise Position Service (PPS) provided Trough of a 30-kHz narrow-beam echo 3-meter cube, was found not to be placed by the Global Position System (GPS). sounder and the 15-kHz Atlas Hydro- as planned. The area surveyed was 400 The differential system uses a static sweep showed good results in by 500 meters with an average depth of GPS receiver at a known location to 9,000 meters thanks to the noise reduc- 130 meters varying about 5 meters. At determine the satellite range correction procedures. In returning to port, 5 knots it took 200 seconds to survey tion for each satellite as it passes by. the Hydrosweep system was used to with about 400 pulses emitted. Pro- These corrections are transmitted to survey the complicated sea bottom off cessing of the data for a bathymetric the user for the position calculation at the Boso Peninsula and was successful map, using their software with a con- sea. The differential GPS (DGPS) in producing a real-time seafloor contour ventional PC, is rapid. For a 40-minute corrections change slowly so that a map.

survey and 4,440 transmissions, it took transmission of one per 20 to 30 seconds Dr. Norman Cherkis of the U.S. 22 minutes to initially process, is sufficient. The improved satellite range Naval Research Laboratory discussed 13 minutes to generate the grid, and information results in a longer survey “Multi-Beam Echo Sounding and 13 minutes to plot the chart on an X-Y window and thus use of low angle satelSeaMARC II Acoustic Imaging in the plotter.

lite passes, which formerly were unacNorwegian Sea." The RV EWING, Mr. Shin Tani of JHD, substituting ceptable. Initial tests of the technique of the Lamont-Doherty Geological for Dr. Takeshi Matsumoto of the Japan were in Hawaiian waters using a comObservatory, during the summer of 1990 Marine Science and Technology Cen- mercial COMSAT earth station faciltook about 22,000 km of track line over ter (JAMSTEC), showed a “Compari- ity. The corrections were eventually the Aegir Ridge in the North Atlantic. son of the Bathymetric Data of HS-10 sent to the Pacific Ocean Region (POR) This cruise combined data from the Multi Narrow Beam Echo Sounder satellite where they were received by Hydrosweep multi-beam echo sounder with Sea Beam Data.” Two surveys of the survey ship DISCOVERY. A with the SeaMARC II acoustic imaging the Japan Trench at a depth below 19-hour test of the system while the system. Data from the ongoing survey 6,000 meters, one by the R/V ship was docked showed an average were transmitted by satellite back to HAKUHO-MARU with a Sea Beam agreement of 5.8 meters. A second test land every third day, where backscatter system in 1990 and the other by the at about 175 nautical miles at sea, analysis was done. This was done to M/S YOKOSUKA in 1991, were used checked with Mini-Ranger lines of determine the amount of acoustic energy to compare the systems. The chart pro- position, showed an average agreement absorbed by the sediment which, in duced from the HS-10 system plots of 7 meters. Technical problems with turn, was used to model sedimentary about 50 meters deeper than that from the transmission terminals and failure features and infer processes, particu- the Sea Beam bathymetry. Small-scale of the Pacific Ocean Region satellite larly in areas where there was no seis- features at such depth seem to be a produced a downtime of 50%. To avoid mic profiling information. The photo problem for the HS-10 system, as such non-DGPS related failures, a joint graphically merged data from the two apparent false features are generated NOAA-U.S. Coast Guard system where

radio beacons are used promises to be useful to within 300 nautical miles of the coast line. The accuracy of this system is thought to be about 10 meters or 2 standard deviations. The radio beacon system was tested in July 1991 on the RUDE using the Montauk Point, New York beacon. Here the MiniRanger and the DGPS positions agreed to about 5 meters. Radio beacon systems are planned for operations in the Gulf of Mexico near Corpus Christi and near Freeport, Texas, and for Cape May, New Jersey, and Cape Henry, Virginia, as well as the Montauk Point beacon. In addition, a "fly-away" DGPS system is being tested. This system is composed of two GPS receivers and a VHF radio data link. The system was tested successfully in Lake Michigan on a 22-foot launch. It is considered that the DGPS systems either fixed or fly-away will become the primary positioning system for mapping, especially in near-shore areas of the EEZ.

Pat Wilde joined the staff of the Office of Naval Research Asian Office (ONRASIA) in July 1991 as a liaison scientist spocializing in occan scicnocs. He received his Ph.D. in geology from Harvard University in 1965. Since 1964, he has been affiliated with the University of California, Berkeley in a variety of positions and departments, including Chairman of Ocean Engineering from 1968 to 1975 and Head of the Marine Sciences Group at the Lawrence Berkeley Laboratory (1977-1982) and on the Berkeley campus (1982-1989). He joined ONRASIA after being the Humboldt Prize Winner in Residence at the Technical University of Berlin. Dr. Wilde's speciality is in paleooccanography and marine geochemistry, particularly in the Paleozoic and Anoxic environments. He maintains an interest in modern occanography through his work on deep-sea fans, coastal and deep-sca sediment transport, and publication of oceanographic data sheets showing the bathymetry with attendant features off the West Coast of the United States, Hawaii, and Puerto Rico.

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