comparing survey results between a multibeam sonar and a
TRANSCRIPT
Comparing Survey Results Between a
Multibeam Sonar and a Multi-Channel
Depth-Capable ADCP
PAT SANDERS, TECHNICAL DIRECTOR, HYPACK YSI
HAROLD ORLINSKY, GENERAL MANAGER, HYPACK YSI
CHC 2016 Conference
The SONTEK M9 Hydrosurveyor ADCP
• ADCP Current Measurements
• Bottom Track Navigation Data
• Echosounder Data
• Capable of measuring depths
as small as 10cm!
• Vertical transducer is 500kHz
• Four transducers at 3MHz
• Four transducers at 1MHz
• It switches automatically
between the 3MHz and 1MHz
transducers as you go from
shallow to deep water.
3MHz and 1MHz transducers are angled
outwards at 25˚ from nadir in a Janus
pattern
Coverage of the system
With the beams at 25 degrees on each side, we can achieve a
coverage of almost 1 times water depth
Coverage = 2 x tan(25) x water depth
In 10 meters of water, the system will give the user an effective
swath of 9.6 meters. Compared to a traditional single beam system
using a 3 degree transducer, and giving a footprint size of 0.5m,
there is a tremendous advantage using this tool
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Our Test Area: Providence, RI
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Surveyed on 1/22/2016 by
USACE with R2Sonic 2040
multibeam and Applanix
POS-MV
Surveyed on 1/29/2016 by
USACE with a SONTEK M9
ADCP and Applanix POS-
MV
Survey Hardware:
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R2Sonic
2040
Applanix
POS-MV
SONTEK
Castaway
HYPACK/HYSWEEP
SURVEY
Network Switch
Bluetooth
Multibeam Configuration
SONTEK
M9
Applanix
POS-MV
SONTEK
Castaway
HYPACK SURVEY
Network Switch
Bluetooth
M9 Configuration
RS-232
PROCESSING
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HSX
FilesMBMAX
XYZ
File
TIN
MODEL
LNW File
DXF
Contours
Sections
R2Sonic Multibeam Data
RAW
FilesMBMAX
XYZ
File
TIN
MODEL
LNW File
DXF
Contours
Sections
RAW
FilesSBMAX
Edited
Files
TIN
MODEL
LNW File
DXF
Contours
Sections
SONTEK M9 Data (MBMAX)
SONTEK M9 Data (SBMAX)
CSV
M9 Data in MBMAX
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M9 Data in SBMAX
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Contour Comparisons
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DREDGE
AREAS
Contoured every 5’ in HYPACK’s TIN MODEL
• Good agreement on slopes
• Noise in M9 data set generates multiple contour artifacts (unsmoothed data)
Multibeam Contours in Blue M9 - MBMAX Contours in Red
Contour Comparisons
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DREDGE
AREAS
Contoured every 5’ in HYPACK’s TIN MODEL
• Good agreement on slopes
• Noise in M9 data set generates multiple contour artifacts (unsmoothed data)
Multibeam Contours in Blue M9 - SBMAX Contours in BLACK
Comparison of Sections Through TIN MODELS
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Multibeam M9 from MBMAX M9 from SBMAX
Why it’s good to have complete coverage…
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Multibeam M9 from MBMAX M9 from SBMAX
Statistical Comparisons
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XYZ MB TIN
MODEL
XYZ
DifferencesMBMAX
M9
XYZ
MB TIN
MODEL
XYZ
DifferencesSBMAX
M9
Mean Difference (cm) Standard Dev. (cm)
MB vs. M9 MBMAX 9 21
MB vs. M9 SBMAX 11 26
The differences between the M9 data processed in MBMAX and SBMAX
is due to different treatments of Sound Velocity (MBMAX routine is better).
Summary
•The depths from the SONTEK
M9 Hydrosurveyor can meet
IHO Order 1A/B survey
standards when combined with
a quality positioning system.
• It’s not going to replace your
multibeam system, but for
hydrographers interested in
obtaining simultaneous current
and depth measurements, it
can reduce redundant systems.
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