SUCCESS STORY
Instrumented Buoys

Wave Buoys in the Arctic Sea Ice
Wave Buoys integrating SBG miniature inertial sensors have been deployed in the Beaufort Sea to understandhow open ocean and in-ice waves impact the floe melting.

CLIENT

LOV/UPMC
UMR 7093
APPLICATIONOpen ocean and in-ice waves
measurement with Wave Buoys
PRODUCT

IG-500A / Ellipse-A miniature
Attitude and Heading Reference
SystemPROJECTOpen ocean and in-ice waves
measurement

Over recent decades the Arctic has
warmed more than any other region
leading to significant reduction insea ice volume. The combinationof increased ice-free area and moremobile ice cover has led to theemergence of a seasonal marginal ice
zone (MIZ) in the Beaufort Sea. The
Office of Naval Research MIZ initiative
engages an integrated programof observations and simulations
to investigate the ice--ocean-atmosphere dynamics with several
autonomous systems including wave
buoys.

IG-500A TO STUDYCHARACTERISTICSWAVESThe program included 25 Wave Buoys
to quantify open ocean and in-ice
wave characteristics and evolution. 20buoys were deployed in the summer
period, 5 in the winter. “We needed avery rapid and cost-effective solution
to measuring directional wave spectrain the ocean. Time to deployment wasvery short, so an integrated solution,
giving us good heave numbers
straight out of the box, was essential.
Delivery time of the units was alsocritical”, indicates Dr. Martin Doble,
oceanographer at the French UPMC
School and member of the researchprogram.
The summer buoys, firstly drilled
into the ice, were powered with solar
panels, and equipped with IG-500A
inertial motion sensors to detect bothdistant and near wave effects on thelocal ice floe. Once the ice melted,
the summer buoys continued tomeasure open ocean characteristics.

«Units were reliable, with no failures in the harsh Arcticconditions. The IG-500As have been running continuously
for over a year without requiring power cycling etc.»
Dr. Martin Doble

SUCCESS STORY - Wave Buoys in the Arctic Sea Ice
ABOUT the Marginal Ice Zone (MIZ)
Program
Emerging Dynamics of the Marginal Ice
Zone (MIZ) is an Office of Naval Research
Departmental Research Initiative. The
goal of this five-year project is to improve
the knowledge and understanding of thephysics of the retreating summer ice edge
and MIZ in the Beaufort and Chukchi seas.
MORE INFO:
www.apl.washington.edu/project/project.php?id=miz

WHEN TEMPERATURECALIBRATION MAKES SENSEThe IG-500A inertial sensors were usedhere for wave height and direction. IG500A measures in real-time roll, pitch,heading accurate to 0.35°, and heave,accurate to 10 cm.

Every sensor is calibrated for bias,
linearity, gain, misalignment, cross-axis
and gyro-g from -40° to +85°C. It allows
them to provide reliable data in harshenvironment, and what can be harsher
than the Arctic ice? “Units were reliable,with no failures in the harsh Arctic
conditions. The IG-500As have beenrunning continuously for over a year
without requiring power cycling etc.,
and the numbers look good, giving clear
results” to quote Dr. Doble.

Hélène Leplomb

WHAT’S NEXT?
“More of the same, using the new
Ellipse units,” says the scientist.
Reliable, ITAR free, and low power,
IG-500 additionally delivered heave
measurement, making them ideal for
instrumented buoys ... before a newseries was launched. During the project,
the Ellipse Series was released, a new

NEW ELLIPSE-A KEY FEATURES

IG-500A KEY FEATURES» 0.2° Roll and Pitch» 0.35° Roll and Pitch» 0.8° Magnetic Heading» 1° Magnetic Heading» Calibrated from -40° to +85°C» Calibrated from -40° to +85°C» 10 cm Auto-adjusting Heave» 10 cm Heave

www.sbg-systems.com

line replacing the IG-500 series. Moreaccurate in attitude and more reliable(IP68) for the same budget, the newminiature inertial sensors now providea heave that automatically adjusts tothe wave period for higher performance.
The Ellipse-A sensors are currently used
in a new ONR project in the Beaufort/
Chukchi Seas.

SBG Systems EMEA (Headquarters)
Phone: +33 1 80 88 45 00
E-mail: sales@sbg-systems.com«We needed a very rapid andcost-eﬀective solution»

Dr. Martin Doble

V1.0 – July– All rights reserved © 2015 SBG Systems

The 5 winter buoys were installed onthe ice. These buoys were made ofaluminium for better resistance andcontained enough batteries to power
them through the dark winter months.
Every buoy also contained processing
and control electronics, an SD card, aGPS, and an Iridium satellite modem
and antennas to transmit the recorded
data on demand to the Cambridgebase station. Summer buoys (openocean waves) and winter buoys (in-icewaves) data were also used together toquantify the wave attenuation rate.

SBG Systems North America
Phone: +1 (773) 754 3272
E-mail: sales.usa@sbg-systems.com