MB-System Unix Manual Page

mbhysweeppreprocess

Section:  MB-System 5.0  (1)
Updated:  21 August 2012 
Index



 

NAME


mbhysweeppreprocess - performs preprocessing of multibeam data
in the Hysweep HSX format (MBIO format 201).


 

VERSION


Version 5.0


 

SYNOPSIS


mbhysweeppreprocess
[-Aoffsettype/x/y/z/t -Brollbias/pitchbias/headingbias
-Dsonardepthfile -Idatalist
-Jprojection  -L
-Mnavformat -Nnavfile
-Ttimelag
-H -V]


 

DESCRIPTION


mbhysweeppreprocess reads a Hysweep HSX (format 201) file, interpolates the
asynchronous navigation and attitude onto the multibeam data,
and writes a new HSX file with that information correctly embedded
in the multibeam data. The user must specify a projection for the easting-northing
navigation used in HSX files. This program can also fix various problems
with multibeam data, and allows for lever arm correction of offsets between the
sonar, the motion sensor, and the positioning sensor (provided the navigation
and attitude data included in the HSX file are uncorrected for sensor offsets)..


 

AUTHORSHIP


David W. Caress (caress@mbari.org)




  Monterey Bay Aquarium Research Institute



Dale N. Chayes (dale@ldeo.columbia.edu)




  Lamont-Doherty Earth Observatory


 

OPTIONS





-A



type/offsetx/offsety/offsetz/offsett



This option sets the spatial and time offset for a sensor relative to a reference
point on the survey platform (by convention usually close to the center of mass and rotation).
If type = 1, the offsets pertain to the survey sonar. If type = 2, the offsets
pertain to the source of the attitude data, usually an MRU or INS. If type = 3, the
offsets pertain to the source of the position or navigation data. The time offsets are
referenced against the sonar data, thus the sonar time offset will usually be zero. If any
of these offsets are defined, then mbhysweeppreprocess will use lever arm calculations
to determine the x, y, and z offsets associated with the platform attitude for each ping, and
add those to the sonar navigation and depth values.

-B



rollbias/pitchbias/headingbias



This option sets roll, pitch, and heading bias values to be applied before merging the attitude
and heading data with the sonar data while calculating bathymetry.

-D



sonardepthfile



This option causes mbhysweeppreprocess to read a sonar depth time series from the specified
file and use that data in place of any sonar depth (DFT) records present in the HSX file. The
sonar depth data must be in an ascii format of the form:

        yyyy:mm:dd:hh:mm:ss.sss zzzz.zzz




where yyyy=year, mm=month, dd=day, hh=hour, mm=minute, ss.sss = seconds, and zzzz.zzz = sonar depth in meters.

-F



format



Sets the format of the input file specified with the -I option. This is normally omitted unless
the input filename does not conform to the MB-System file naming conventions. For this
program, the only relevant options are format = 201 for an HSX format file, or
format= -1 for a datalist referencing multiple format 201 files.

-H



This "help" flag cause the program to print out a description
of its operation and then exit immediately.

-I



infile



Sets the input file path. If format > 0 (set with the
-f option or mbdefaults) then the swath sonar data contained in infile
is read and processed. If format < 0, then infile
is assumed to be an ascii file containing a list of the input swath sonar
data files to be processed and their formats.  The program will read
the data in each one of these files.
In the infile file, each
data file should be followed by a data format identifier, e.g.:

        datafile1 201


        datafile2 201




This program only reads Hysweep HSX format data files (MBIO
format 201).

-J



projection



The Hypack and Hysweep software packages operate with navigation in a user-defined
projected coordinate system. Resultantly, HSX format files contain positions in a
projected coordinate system rather than longitude and latitude in geographic
coordinates. Generally, the HSX files do not contain any description of the projection
used to obtain the eastings and northings in those files. This option allows a
user to specifiy the projection used to translate the eastings and northings back
into longitude and latitude. If this option is not specified, MB-System will
assume the data are associated with UTM zone 1 north. The projection identifier must
conform to the same usage as with projections specified for mbgrid.
For  instance, to fully specify a particular northern UTM zone, set projection = UTMXXN
where XX gives the UTM zone (defined from 01 to 60). As an example, a northern UTM
zone 12 projection can be specified using -JUTM12N.  Southern UTM zones are specified as
UTMXXS. The European Petroleum Survey Group (EPSG) has defined a large number of PCS's
used worldwide and assigned number id's to each; one can also specify the northern
UTM zone 12 projection using its EPSG designation, or -Jepsg32612. The complete list
of projected coordinate systems supported by MB-System is given in the mbgrid
manual page.

-L






This option causes the program to list the timetags of bathymetry,
navigation, attitude, and other data records.

-M



navformat



Sets the input navigation file format used by the file specified with the
-N option.

 At present, the only option for the navigation file format is navformat=1:

        yyyy:mm:dd:hh:mm:ss.sss sssss.sss eeeeeeee.eee nnnnnnnn.nnn zzzz.zzz aaa.aaa hhh.hhh




where yyyy=year, mm=month, dd=day, hh=hour, mm=minute, ss.sss = seconds, sssss.sss = seconds
from the start of the year, eeeeeeee.eee = easting in meters, nnnnnnnnn.nnn = northing in
meters, zzzz.zzz = sonar depth in meters, and hhh.hhh = heading in degrees.
Default: navformat=1.

-N



navfile



The program will read navigation from the file navfile
and merge those data with the multibeam data in the HSX file.
If a timelag model is specified using
-Ttimelag, the time lag will be applied to the navigation and
attitude data before merging with the sonar data. The navigation and attitude
data from navfile will also be embedded in asynchronous data records
in the output format 201 data. Any pre-existing navigation data records will
remain unchanged in the data stream. However, the HSX file header will be altered
to show the newly merged data as "enabled" and the original, asynchronous data
as not enabled.

-T



timelag



This option specifies a timelag value in seconds to be applied
to the navigation and attitude data prior to it being merged with the
bathymetry. If timelag is a valid path to a file containing time
stamp and time lag pairs, then these data will be read and the time lag
applied to particular records will be interpolated by time.

-V



This option increases the verbosity of mbhysweeppreprocess with
respect to informational output to the shell.




 

EXAMPLES


Suppose that one has logged a set of five HSX files incorporating
multibeam sonar data, navigation, attitude, heading, and altitude data,
but not sonar depth data, all from an ROV platform. Further suppose
that a datalist file named datalist_hsx.mb-1 references those
files, and that a separate text file named  ROVnav.txt includes
an improved vehicle navigation, including the sonar depth. Finally,
suppose that the existing sensor offsets are known, but have not
been applied to any of the existing data



In order to merge the better navigation and sonar depth before
starting MB-System processing, do something like:




        mbhysweeppreprocess -I datalist_hsx.mb-1                        -A1/0.42/2.005/-1.34/0.0  -A2/0.46/0.22/0.55/0.0  -A3/0.46/0.22/0.55/0.0  -JUTM01N -NROVnav.txt




The program will output something like the following:

        Data available for merging:


             Navigation (northing easting sonardepth altitude heading): 120959


             Sonar depth (sonardepth):                                  0


             Time lag:                                                  0




        Offsets to be applied:


                       X (m)   Y (m)   Z (m)   T (sec)


             Roll bias:       0.000


             Pitch bias:      0.000


             Heading bias:    0.000


             Sonar:    0.420    2.005   -1.340    0.000


             MRU:      0.420    2.005   -1.340    0.000


             Nav:      0.420    2.005   -1.340    0.000




        Data records read from: 000_2004.HSX


             Positions (POS):                   2651


             Positions ignored (POS):           0


             Heading (GYR):                     19486


             Attitude (HCP):                    15752


             Echosounder (altitude) (EC1):      2651


             Dynamic draft (DFT):               0


             Raw multibeam (RMB):               24438


             Other:                             64978




        Data records read from: 000_2048.HSX


             Positions (POS):                   2967


             Positions ignored (POS):           0


             Heading (GYR):                     21942


             Attitude (HCP):                    17771


             Echosounder (altitude) (EC1):      2967


             Dynamic draft (DFT):               0


             Raw multibeam (RMB):               25363


             Other:                             71010




        Data records read from: 000_2138.HSX


             Positions (POS):                   2573


             Positions ignored (POS):           0


             Heading (GYR):                     18936


             Attitude (HCP):                    15307


             Echosounder (altitude) (EC1):      2573


             Dynamic draft (DFT):               0


             Raw multibeam (RMB):               23398


             Other:                             62787




        Data records read from: 000_2221.HSX


             Positions (POS):                   2824


             Positions ignored (POS):           0


             Heading (GYR):                     20863


             Attitude (HCP):                    16907


             Echosounder (altitude) (EC1):      2824


             Dynamic draft (DFT):               0


             Raw multibeam (RMB):               23993


             Other:                             67411




        Data records read from: 000_2308.HSX


             Positions (POS):                   2657


             Positions ignored (POS):           0


             Heading (GYR):                     19571


             Attitude (HCP):                    15818


             Echosounder (altitude) (EC1):      2657


             Dynamic draft (DFT):               0


             Raw multibeam (RMB):               24009


             Other:                             64712




        Total data records read from: datalist_hsx.mb-1


             Positions (POS):                   13672


             Positions ignored (POS):           0


             Heading (GYR):                     100798


             Attitude (HCP):                    81555


             Echosounder (altitude) (EC1):      13672


             Dynamic draft (DFT):               0


             Raw multibeam (RMB):               121201


             Other:                             330898




        Data records written to: 000_2004.mb201


             Positions (POS):                   2651


             Positions ignored (POS):           0


             Heading (GYR):                     19486


             Attitude (HCP):                    15752


             Echosounder (altitude) (EC1):      2651


             Dynamic draft (DFT):               0


             Raw multibeam (RMB):               24438


             Other:                             0




        Data records written to: 000_2048.mb201


             Positions (POS):                   2967


             Positions ignored (POS):           0


             Heading (GYR):                     21942


             Attitude (HCP):                    17771


             Echosounder (altitude) (EC1):      2967


             Dynamic draft (DFT):               0


             Raw multibeam (RMB):               25363


             Other:                             0




        Data records written to: 000_2138.mb201


             Positions (POS):                   2573


             Positions ignored (POS):           0


             Heading (GYR):                     18936


             Attitude (HCP):                    15307


             Echosounder (altitude) (EC1):      2573


             Dynamic draft (DFT):               0


             Raw multibeam (RMB):               23398


             Other:                             0




        Data records written to: 000_2221.mb201


             Positions (POS):                   2824


             Positions ignored (POS):           0


             Heading (GYR):                     20863


             Attitude (HCP):                    16907


             Echosounder (altitude) (EC1):      2824


             Dynamic draft (DFT):               0


             Raw multibeam (RMB):               23993


             Other:                             0




        Data records written to: 000_2308.mb201


             Positions (POS):                   2657


             Positions ignored (POS):           0


             Heading (GYR):                     19571


             Attitude (HCP):                    15818


             Echosounder (altitude) (EC1):      2657


             Dynamic draft (DFT):               0


             Raw multibeam (RMB):               24009


             Other:                             0




        Total data records written from: datalist_hsx.mb-1


             Positions (POS):                   13672


             Positions ignored (POS):           0


             Heading (GYR):                     100798


             Attitude (HCP):                    81555


             Echosounder (altitude) (EC1):      13672


             Dynamic draft (DFT):               0


             Raw multibeam (RMB):               121201


             Other:                             0



 

SEE ALSO


mbsystem(l), mbformat(l), mbinfo(l)


 

BUGS


At this point, the HSX i/o module and preprocessor are only tested with a single
survey of R2Sonic data.





 
Index




NAME


VERSION


SYNOPSIS


DESCRIPTION


AUTHORSHIP


OPTIONS


EXAMPLES


SEE ALSO


BUGS


Last Updated: 21 August 2012

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