tim mcginnis* bruce m. howe university of washington applied physics lab *...
TRANSCRIPT
Tim McGinnis*
Bruce M. Howe
University of WashingtonApplied Physics Lab
ALOHA Observatory Moored Sensor Network
with Adaptive Sampling
Introduction
• Overview
• Science Objectives/Opportunities
• Project Team
• User and System Requirements
• Preliminary Design
• System Description
• Major Components
• Sensor Suite
• Schedule
• Outstanding Issues
Overview – HOT Site
• Hawaii Ocean Time-series “HOT” Site – 3 Stations: Kahe, Kaena & ALOHA– monthly cruises for 15 years– ALOHA Station 100km N of Oahu
HOT Science
• Mexican sub-mesoscale eddy (“Meddy”)
• Discovered on ship- based CTDO2 cast at ALOHA
• 200m vertical extent in mid-water with no surface signature
• Extremely low O2 and high salinity are unprecedented
•Water sample analysis showed that the highly anomalous waters were unambiguously from offshore Baja California
• Rare event (1 in 15 years) or were others missed due to intermittent sampling?
From Lukas and Santiago-Mandujano, 2001
HOT Science
• Intermittant, cold abyssal overflow from Maui Deep to Kauai Deep
• These overflows cause large enhancement of diapycnal (nearly vertical) mixing with global impacts
• What forces these overflows? How should they be modeled?
• Is this “sloshing over the rim” and associated mixing common to deep ocean basins?
HOT Science
• Profiles from CTD cast at HOT site
• Large spikes in fluorescence (at 125, 134 & 141 dbars) are associated with steps and layers in density
• Did turbulent overturns homogenize the density in the layers with the suspended materials sinking to the bottom of the layer?
• To what degree do such optical signals correspond to turbulent overturning?
• How many similar cases are missed with monthly cruises & casts?
ALOHA Observatory
• Utilize a retired telecommunications cable and install observatory node at HOT site
•Originally planned to use analog coax ANZCAN cable – now plan to use optical HAW-4 cable (shown at left)
• Replace monthly cruises with combination of:
- sustained in-situ observations (seafloor sensors, moorings, gliders, etc.)
- several ship cruises per year (process oriented measurements)
Overview - ALOHA Observatory Mooring (AOM)
• Major Components– Seafloor sensor suite & junction box– Subsurface float at ~200m depth with sensor
suite and junction box– Mooring profiler with sensor suite that can
“dock” with the float for battery charging, data download and command upload
– 4500m electro-optical mooring cable
• Features– Cable connection provides high power and
real-time communications– Enables adaptive sampling– ROV servicing and installation of sensors
• Deployments– 2004-5 on VENUS Observatory in Saanich
Inlet, B.C.– 2005-6 on ALOHA Observatory at HOT Site,
100 nm N of Oahu
Project Team
• University of Washington, Applied Physics Lab• Bruce Howe, PI, Principle Investigator• Tim McGinnis, Co-PI, Electrical & System Engineering• Jason Gobat, Co-PI, Mooring Design, Sensor Integration• Jim Mercer, Co-PI, ALOHA Observatory Interface• Vern Miller, Mechanical Engineering• Chris Siani, Electrical Engineering• Mike Kenney, Software Engineering• Tim Wen, Software Engineering• Janet Olsonbacker, website design
• University of Hawaii• Roger Lukas, Co-PI, Data Management, Outreach
• University of Maine• Emmanuel Boss, Co-PI, Optical Sensors & Data Analysis
System Engineering
User Requirements
System Requirements
System Design
User Requirements
• Provide water column current profiling for entire water column• Near continuous in-situ profiling from near surface to seafloor with CTDO, ACM, optics, • Profiler rate of advance to allow 1 sampling cycle per tidal half cycle (6 hours)• Profiler charging time (in dock) must be less than 6 hrs• Profiler duty cycle must be greater than 90%• Profiler sampling rate and profiling depth range must be controllable• Provide extra Science User Connectors with “standard” power and data interface on float and seafloor• Provide real-time, high bandwidth communication for Science User instruments
System Requirements
• Compatible with ALOHA power and data interfaces• Power load on ALOHA must be constant power within +/- 10%• Provide 12Vdc (?), 48Vdc and 400Vdc (?) power and 10/100BaseT communications at Science User Connectors• Provide connection method for standard RS-232 sensors• ROV serviceable j-boxes• Operational life of > 2 years• Located > 2 km from ALOHA node to allow ROV access to ALOHA node and instruments
Goals
• Provide video at Float and Seafloor J-boxes and on still camera Profiler• Profiler mountable/removable by ROV• Profiler rate of 40 cm/sec (standard is 25 cm/sec)
Block Diagram: ALOHA – Anchor J-box
anchorcomputer
ethernetswitch
powerconversion
&distribution
loadmonitoring& control
CTDO22
Seafloor J-Box
electro-optical
converter
data
4500melectro-opto-mechanical
mooring cable
electro-optical
converter
power
cabletermination
cabletermination
cabletermination
electro-optical
converter 2000mE-O
cable
ALOHA Interface pressure housing
ALOHAj-box
power
Optics
CTDO21
dataconversion
powerconversion
data
OpticsCable to Oahu
User ScienceConnectors (4)
Block Diagram: Float – Profiler
dc-hfacconverter
batterybank
hfac-dcconverter
batterycharger
battery bank
profilercontroller
floatcomputer
modem modem
batterycharger
ethernetswitch
powerconversion
&distribution
powerconversion
&distribution
framegrabber
CTDO21
CTDO22
MMPTT8
Controller
ADCP
CTD1
ACM
RS-232
RS-232
electro-optical
sliprings
RS-232
videocamera
Float J-Box MMP pressure housing
MMP motor
electro-optical
converter
4500melectro-opto-mechanicalriser cable
RS-232
Optics
Optics
datacoupler
powercoupler
CTDO22
transponder
Optics
Science UserConnectors (4)
control &monitoring
Junction Boxex – Float & Seafloor
• On Seafloor near Anchor & on Float • 4 User Connectors
• Data Communications• 10/100BaseT• RS-232/422 (?)
• Power - ~200W total• 400 Vdc (? no large or remote loads)• 48 Vdc• 12 Vdc (? probably more common)
• Installed Sensor Suite• 2 x CTDO
• Optics – transmissometer, fluorometer, CDOM, other (?)• ADCP (on Float)• Video on Float and Seafloor (goal)
Junction Box – Float & Seafloor
ROV mateableConnector
ROV mateableConnector
ROV mateableConnector
Ethernet SwitchControl &Monitoring
Relay Relay
CurrentSensor
CurrentSensor
ROV mateableConnector
ROV mateableConnector
Low Voltage DCDistribution
CurrentSensor
Relay
CurrentSensor
400V-5/12/48 VDCDC-DC Converter
400V
CurrentSensor
GFI GFI GFI
GFI
Relay
GFI
J-BoxController
Junction Boxes – Float & Seafloor
• Inherited from NEPTUNE/MARS development• Node Controller hardware and software• Shore power control and monitoring, archiving, GUI• Load control – switching, over current, ground fault• DC-DC converters• ROV mateable connectors
• New Development• Small Ethernet switch• Ethernet – RS-232 conversion• Ethernet electrical-optical conversion
Observatory – Instrument Interface
• Embedded Device Servers- 10/100BaseT Ethernet- Multiple RS-232 ports- Memory space for metadata/embedded website- TCP, UDP, SNMP, DHCP, etc.- Auxiliary I/O lines
…….or could have multi-port serial hub in the J-Box and use serial through the User Science Connectors
Observatory – Instrument Interface Examples
10/100BaseTEthernet
48/400 VDC
Instrumentwith EthernetInterface and
Metadatastorage
Ethernet
Instrumentwith SerialInterface
DeviceServer withMetadata
Ethernet
ObservatoryJunction Box
48V
48V RS-232
"ObservatoryReady"
Instrument
Instrument withSerial Interface
DeviceServer withMetadata
Ethernet
48V
SerialInstrument
with InternalDevice Server
RS-232
SerialInstrument
with ExternalDevice Server
Instrumentwith SerialInterface
SerialInstrument withDevice Server
in J-Box
Device Serverwith Metadata
Electrical-Optical Conversion
• ROV mateable electro-optical connectors very expensive (~$20k) and not likely to be used extensively on observatories for instrument connection
•ROV mateable electrical connectors are lower cost (~$2k) and will be used on MARS, VENUS and ALOHA
• Fiber optic cables are required for data transmission > 100m
• Transmission distances up to 100 km
• COTS ethernet electrical-optical converter available for operation in 10kpsi oil (~$2k)
Electrical-Optical Conversion
• Allows use of standard ROV connector with copper conductors for Ethernet communications over long distances
• Cost significantly less than E-O hybrid connector
ROVmateable
receptaclej-box
ROVmateable
plug
PBOFhose
oil filledhousing with
E-Oconverter
E-Openetrator
E-O cable
400V (copper)
100Base-TX (copper)
100Base-FX (fiber)
PBOFhose
electricalpenetrator
5V (copper)
McLane Mooring Profiler
• 6000m depth rating• Trajectory and sampling schedule programmable pre-deployment• Resistant to cable fouling• 1 M meters of travel per battery charge•Standard sensors
• CTD• 4 axis Acoustic Current Meter (ACM)
• ~40 units sold
McLane Mooring Profiler Modifications
• New motor, gearbox, wheel re-design to fit larger EOM cable (~18mm)• Mount 2nd CTD, optical sensors• Interface AOM controller to their modem port to offload data after every profile• Replace primary Li batteries with rechargeable Li-Ion• Plan to use existing McLane housing• Modify cable mounts & retainer for ROV servicing (goal)• Profiling rate will be set by gearbox – not controllable – 25 cm/s (std), 40cm/s (goal)• Need to decide on profiling and charging times (4 days/4 hours looks achievable with reasonable size battery packs.)
CTD
Mooring Cable
Glass Spheres Transponder
Controller Housing
Guide Wheel and Cable Retainer
Drive Motor
Guide Wheel and Cable Retainer
ACM Sting CTD
ACM Electronics
ACM Sting
Float/Dock Configuration
MooringProfiler
CableTermination
SlipRing
Power & DataInductiveCoupler
ObservatoryPower & DataConnection
Profiler Power& Data
Transfer
MooringEOMCable
FLOAT
ProfilerCTD
ProfilerCurrentMeter
Coupler Primary & Secondary
Seafloor Node
Float SIIM
• ROV serviceable using “fork lift”
Deployment Frame
Inductive Coupler
Guide (attached to Float)
Primary Core
Compliant Mount
Secondary Core
Secondary Guide
Charger Cable
From S&K Engineering, Inc.
Concerns:- biofouling- robustness- holding profiler in place during charging
Inductive Coupler
Guide (attached to Float)
Primary Core
Secondary CoreGuide
Mooring cable
Secondary CoreAngled core interface
From S&K Engineering, Inc.
Power Budget Estimate
• Seafloor J- Infrastructure 10 W• Anchor Sensors 35 W• Sediment Trap Mooring (K. Smith) 50 W• Float Infrastructure 10 W• Float Sensors 40 W• Float Battery Trickle Charging 5 W• Conversion and Transmission Loss 50 W• ALOHA Supply 200 W
Sensors
• Float- ADCP (w/tilt, heading ?)
- CTDO – Dual
- Transmissometer
- CDOM
- Other optics ?
- Video/lights
- Argos transmitter ?
- Light ?
- Acoustic Transponder ?
- Engineering Sensors
mooring cable load cell ?
• Anchor
- CTDO – Dual
w/precision depth
- Transmissometer
- CDOM
- Other optics ?
- Video/lights ?
• Profiler- Stock sensors
CTDO – Dual
ACM
- Transmissometer
- CDOM
- Other optics ?
- Video/still camera/lights ?
Schedule
03 CY2004 CY2005 CY2006
Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
Preliminary Design
Design Review
Detail Design
Procure & Fabricate
Assembly
Shop Test
Puget Sound Test
VENUS Deployment
VENUS Recovery
Critical Design Review
Final Procurement - Redesign
ALOHA Deployment
ALOHA Maintenance
ALOHA Recovery (?)
Outstanding Issues
• Need ALOHA Interface specs • Float depth of 200m – want to get below light (biology) & surface waves• Fishbite protection on the mooring wire would add a layer to the cable and complicate profiler movement. Do we need it?• Use “standard” Observatory ROV mateable connectors and instrument interface• Need good precision survey of site – water depth of mooring site•