U.S. Geological Survey, 2010, HYPACK_NAVIGATION: Text files of the Differential Global Positioning System (DGPS) and Real-Time Kinematic (RTK) navigation logged with HYPACK software by the U.S. Geological Survey during Cruise 08016 within the St. Clair River between Michigan and Ontario, Canada, 2008.: Open-File Report 2010-1035, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.This is part of the following larger work.
Denny, Jane F. , Foster, David S. , Worley, Charles R. , and Irwin, Barry J. , 2010, Geophysical data collected from the St. Clair River between Michigan and Ontario, Canada, 2008-016-FA: Open-File Report 2010-1035, U.S. Geological Survey, Woods Hole Coastal and Marine Science Center.
Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.000001. Longitudes are given to the nearest 0.000001. Latitude and longitude values are specified in Decimal degrees.
The horizontal datum used is D_WGS_1984.
The ellipsoid used is WGS_1984.
The semi-major axis of the ellipsoid used is 6378137.000000.
The flattening of the ellipsoid used is 1/298.257224.
FTP: The first record located at the top of the header used to identify the file format.
VER: HYPACK version number.
INF: General survey information filled in by the data technician. . This typically contains the survey participants, the vessel name, other agencies involved with the survey, and the location of the survey. The three numbers at the end refer to initial tide correction at start-of-line, initial draft correction at start-of-line and sound velocity from the navigation parameters.. This information was not filled in correctly in 000_1141.150. All other files are correct.
FIL: Raw format file.
ELL: Ellipsoid information. The name of the ellipsoid followed by the semi-major axis in meters and the flattening ration.
PRO: Project information record where TME indicates Transverse Mercator and the central meridian of -81 indicates UTM, zone 17.
DTM: Datum transformation record
GEO: Geoid model. Blank if not present.
HVU: Horizontal and Vertical Units (meters).
TND: Survey time and date in UTC.
DEV 0: Indicated that the lines collected with device designation 0 are using DGPS receiver (CSI LGBX Pro)
OFF: device offsets (none used during this data collection) The number following OFF indicates which device
DEV 1: Indicates that lines collected with device designation 1 are referencing Furuno single-beam echo sounder
DEV 2: Indicates that lines collected with device designation 2 are using Ashtech Z-Extreme, capable of recording antenna elevations above a vertical datum (i.e. real-time kinematic, RTK)
DEV 3: Indicates that lines collected with device designation 3 are referencing Knudsen Chirp profiler
PRD: Private Device Data (disabled)
LIN 2: planned line data follows
PTS: planned line waypoints (eastings and northings, UTM, zone 17N, meters)
LBP: planned line begin point (easting and northings, UTM zone 17N, meters)
LNN X: planned line name, where X is the line number
EOL: end of planned line
EOH: end of header
The remaining elements have similar information in the first 3 columns. The first column will indicate the data type, the second column will indicate the device that recorded the information (e.g. 1 for Ashtech receiver) and the third column is the time tag (seconds past midnight) that is also sometimes referred to as the latency. The remaining information on each line is specific to the data type.
GYR: Gyro Data (Heading). Format GYR dn t h, where dn=device number, t=time tag (seconds past midnight), h=ship heading angle.
MSG: Message string in the format "MSG dn t message" where dn=device number; t=time tag (seconds past midnight); message is the message sent from the device.
EC1: echo sounding (singe frequency). Format EC1 dn t rd, where dn=device number, t=time tag (seconds past midnight), rd=raw depth.
POS: Position of the ship in the format "POS dn t x y" where dn=device number; t=time tag (seconds past midnight); x=easting; y=northing. On this cruise these values are in UTM, Zone 17, WGS84.
QUA: Position quality information in the format "QUA dn t n m h sat mode" where dn=device number; t=time tag (seconds past midnight); n=number of values to follow; m = 10 minus HDOP (horizontal dilution of precision); h=HDOP; sat=number of satellites; mode=GPS mode (NMEA 0183 standard values) where 0=fix not available or invalid; 1=GPS fix; 2=Differential GPS fix; 3=GPS PPS Mode fix; 4=RTK fix; 5=RTK float.
RAW: Position information in the format "RAW dn t n lat long alt utc" where dn=device number; t=time tag (seconds past midnight); n=number of values to follow; lat=raw latitude X 100; long=raw longitude X 100; alt=antenna altitude above ellipsoid (meters); utc=GPS time in the format HHMM.
FIX: Fix (event) mark. Format FIX vn, where n=FIX format version number, Always 2nd record in file.
The (National Marine Electronics Association) NMEA strings $GPGGA, $GPVTG, and $GPZDA are stored in the HYPACK file. These are defined as follows.
$GPGGA is GPS fix data in the format "$GPGGA, t, lat, lath, long, longh, q, sat, h, a, M, alt, M, t2, refcheck" where t=time in UTC in the format hhmmss.ss; lat=latitude in the format ddmm.mmmmmm; lath= N or S indicating the latitude hemisphere; long=longitude in the format dddmm.mmmmmm; longh=E or W indicating the hemisphere; q=fix quality where 0=fix not available or invalid; 1=GPS fix; 2=Differential GPS fix; 3=GPS PPS Mode fix; 4=RTK fix; 5=RTK float; sat=number of satellites; h=Horizontal Dilution of Precision (HDOP); a=Antenna altitude above mean sea level (geoid); M= units of antenna altitude in meters; alt=height of geoid above WGS84 ellipsoid; M=units of geoidal height in meters; t2=time since last DGPS update; refcheck=DGPS reference station id and the checksum.
Example: $GPGGA,163052.00,4118.964217,N,07036.966471,W,4,10,00.9,00005.332,M,-030.544,M,01,*57 UTC Time = 163052 Latitude = 4118.964217 N Longitude = 7036.966471 W Fix Quality = 4 Number of satellites = 10 HDOP = 00.9 relative accuracy of horizontal position Altitude = 5.332 meters above mean sea level Height of geoid above WGS84 ellipsoid = -30.554 meters Time since last update = 01 Checksum = *57.
$GPVTG is track made good and ground speed in the format $GPCTG, true, T, mag, M, grsp, N, grdp, K, mode, where t=true course made good over ground in degrees, T= True, m=magnetic course made good over ground in degrees, M=magnetic, gdsp=ground speed, N=Knots, grsp=ground speed, K=Kilometers per hour, mode=Mode indicator (A=Autonomous, D=Differential, E=Estimated, N=Data not valid).
Example: $GPVTG,089.23,T,104.82,M,004.86,N,009.02,K,D*28 True course made good: 089.23 Magnetic course made good: 104.82 Ground speed (knots) = 4.86 Ground speed (kilometers) = 9.02 Mode=Differential
$GPZDA is UTC Date/Time and Local Time Zone Offset in the format $GPZDA,hhmmss.ss,xx,xx,xxxx,xx,xx where hhmmss.ss=UTC, xx=Day, 01 to 31, xx=month, 01 to 12, xxx=Year, xx=Local zone description, 00 to +/- 13 hours, xx=Local zone minutes description (same sign as hours), checksum.
Example: $GPZDA,163053.00,09,08,2007,,*60 UTC= 163053.00 UTC day = 09 UTC month = 08 UTC year = 2007 Local zone hours = null Local zone minutes = null Checksum = *60
508-548-8700 x2311 (voice)
These data are supplied to provide the raw navigation collected by an Ashtech Z-Extreme receiver and logged using HYPACK, Inc. navigation software (www.hypack.com). RTK navigation was not incorporated to any of the geophysical systems during data acquisition. These data were stored in order to post-process the RTK navigation to provide improved vertical and horizontal accuracies for the swath bathymetric data. RTK provides accuracies on the order of 10s of centimeters (<http://www.navcen.uscg.gov/>).
Person who carried out this activity:
(508) 548-8700 x2311 (voice)
(508) 457-2310 (FAX)
Foster, David S. , and Denny, Jane F. , 2009, Quaternary Geologic Framework of the St. Clair River between Michigan and Ontario, Canada: Open-File Report 2009-1137, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.
HYPACK, Inc., 2009, HYPACK Hydrographic Survey Software User Manual.
A DGPS antenna, connected to an Ashtech Z-Xtreme receiver, was attached at the center of the rigid horizontal pole used to mount the Octopus F180R Attitude and Positioning system antennas. The DGPS navigation was used to record horizontal position during data acquisition.
DGPS navigation was used to record horizontal and vertical position (x,y,z) of bathymetric soundings during data acquisition aboard the USGS R/V Rafael. An additional DGPS antenna, connected to an Ashtech Z-Xtreme receiver, was attached at the center of the rigid horizontal pole used to mount the Octopus F180R Attitude and Positioning system antennas. Real Time Kinematic GPS (RTK-GPS) corrections were applied to the Ashtech Z-Xtreme navigation data during post-processing in order to provide sub-meter vertical accuracy for bathymetric soundings. Fort Gratiot, MI, a Continuously Operating Reference Station (CORS) (<http://www.ngs.noaa.gov/CORS/>), was used as the reference station for the RTK-GPS corrections. A rover RTK-GPS station was established at the tidal benchmark at the U.S. Coast Guard Base at Port Huron in order to determine the offset between North American Vertical Datum of 1988 (NAVD 88) (vertical datum referenced at the CORS site) and the International Great Lakes Datum 1985 (IGLD 85) referenced at the tidal benchmark. The following offsets were applied to the shipboard DGPS data during post-processing: vertical offset between NAVD 88 and IGLD 85, the measured distance between the DGPS antenna and SWATHplus transducer, and the depth of the transducer below the water line. The resulting values were applied to the bathymetric soundings during processing to provide a measure of depth relative to IGLD 85.
These files represent all the Differential GPS and real-time kinematic (RTK) navigation recorded by the HYPACK software during USGS cruise 08016 within the St. Clair River between Michigan and Ontario, Canada, 2008.
These are the original raw data files recorded by the HYPACK navigation software. No additional checks or corrections have been made to these files.
Are there legal restrictions on access or use of the data?
- Access_Constraints: None
- Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset.
508-548-8700 x2311 (voice)
Neither the U.S. Government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials.
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
|Data format:||This WinZip file contains the ANSI text HYPACK navigation files as well as the associated metadata files. in format WinZip (version 9.0) Size: 12463 KB|
The user must have software capable of uncompressing the WinZip file, such as WinZip or pkUnzip.
(508) 548-8700 x2311 (voice)
(508) 457-2310 (FAX)