1. Bruce M. Howe, Timothy McGinnis, Jason Gobat, APL-UW
Mooring Sensor Network for Ocean Observatories: Continuous, Adaptive Profiling
Bruce M. Howe, Timothy McGinnis, Jason Gobat, APL-UW
Roger Lukas, UH
Emmanuel Boss, UMaine
ORION Meetings
Washington DC
19 – 21 October 2005

3. Outline Introduction and motivation Moorings ALOHA-MARS Mooring design
Questions and issues
Main point
we are developing ORION sensor network infrastructure and making many decisions on our own
ideally coordinated
what can this committee do to help in the future?
too late for this particular project – but suggestions still welcome!

4. Introduction – 1
A major effort and cost in the lifetime of an ocean observatory system will be in the sensor networks
Here – the sensor network infrastructure part
Terminology:
Backbone infrastructure provides primary junction boxes/nodes
Sensor networks = (sensors/instruments + sensor network infrastructure)

5. Introduction – 2 Sensor network infrastructure Includes
everything between sensors and backbone nodes
called science instrument interface modules (SIIMs)
definitions and terminology still evolving
Includes
“secondary” cable and junction boxes,
connectors, in-line converters, “pucks”,
sensor “platforms”, moorings, winches, fixed and mobile (profilers, AUVs, gliders, rovers)
down-borehole arrays, moles, …
associated O&M
and more - the user tool kit

6. Need for profiling moorings in ORION and ocean observatories
Reduce temporal and spatial aliasing in vertical sampling of the ocean, e.g., at tide and internal wave frequencies and space scales
Deliberately intensive sampling of fine vertical structure — Meddies/coherent eddies, biological thin layers, overflows, etc.
Sampling of episodic or otherwise non-stationary flow
Less expensive than many fixed instruments

7. Example: Fully loaded mooring (Daly et al. 2005)
Two platforms for remote sensing and point instruments
Two profilers
Tomography source and receiver
Bottom instrument suite
Two moorings better?
Fixed
Profiling (one unit)
More robust?

8. ALOHA-MARS Observatory Mooring
Features
Enables adaptive sampling
Distributes power and communications capability throughout the water column
ROV servicing
Major Components
Subsurface float at ~165 m depth with sensor suite and junction box
Mooring profiler with sensor suite that can “dock” for battery charging, continuous two-way communications
Electro-optical-mechanical mooring cable
Seafloor sensor suite & junction box
Deployments
2006 on Seahurst Observatory in Puget Sound, 30 m depth
on MARS in Monterey Bay, 900 m depth

9. User Requirements Current profiling for entire water column
Near continuous in-situ profiling from near surface to seafloor with CTDO2, ACM, bio-optics
1 cycle per tidal half cycle
Non-stop run time > 3 days
Duty cycle > 90%
Depth range controllable
Provide extra Science User Connectors with “standard” power and data interface on float and seafloor

10. System Requirements
Compatible with MARS/NEPTUNE/VENUS/ORION global buoys (and others) power and data interfaces
Provide 48Vdc and 400Vdc power and 100BaseT communications at Science User Connectors; provide interface for RS-232 sensors at 12 V and 48V
Timing: ~1 ms required, ~microseconds desired (future acoustics)
ROV-serviceable secondary junction boxes and connections
Operational life of > 2 years
Located 1.5 km from MARS node to allow ROV access to MARS node and other instruments

11. Wish List
Profiler (and other active components) install/remove/service by ROV
Larger profiler, larger payload, faster
Higher data rate (> present 1200 baud) communication with profiler
More power transfer
Multiple docks and profilers on a single mooring
More sensors
Broadband hydrophone/transducer array, fixed, profiling
Bio-optics
Still/video
pCO2

12. Float and MMP ROV-serviceable instrument platform
Inductive power coupler
MMP

13. Subsurface Float Instrument SIIM bays Ti center post in slot
2ndary J-box electronics
(with IPC, SIM, ADCP, camera)
Guard rail
SIIM
ROV-mateable
connectors
Float, 3000 lbs buoyancy
ROV-positioning pins
Swivel, 12-elect
Termination (with E-O converter)
Cable, inch, 4 fiber
6 conductor, kevlar, fishbite

14. Float SIIM Lifting bale Electronics (will replace ADCP in this figure)
ROV-mateable
connector
CTDs, Bio-optics
Latch
ADCP and camera will be permanently mounted on float, use 2ndry node
ROV “fork” slots

15. McClane Mooring Profiler (MMP)
6000 m depth rating
Mission sampling programmable
Resistant to cable fouling
1 Mm of travel per battery charge (50 days)
Standard sensors
CTD
2-d Acoustic Current Meter (ACM)
~40 units sold

16. McLane Mooring Profiler Modifications
Add inductive power transfer
Rechargeable Smart-Li-Ion batteries, 90% duty cycle (4 days on, 4 hr charge)
Add inductive communications – Sea-Bird 1200 baud real time
Add controller to interface to
MMP controller
Comms inductive modem
Battery monitor
Sensors (BB2F, etc)
New drive wheel - larger EOM cable (~21 mm)
Keep 0.25 m s–1 speed
Sensors: Seabird CTDO2, FSI Acoustic Current Meter (ACM), WetLabs Red/Blue Backscatter and Fluorometer (BB2F)
Lengthen, add sphere

17. Inductive Power Coupler
S&K Engineering
Need < 2 mm gap
Efficiency ~70%
200 W transfer
10 kHz
MMP electronics includes 24 V battery charging
Concerns:
Biofouling
Robustness
Docking
Holding profiler in place during charging
Primary on cable
Secondary on MMP
Attach to MMP, 2-inch spring

18. Seafloor Secondary Node
Stainless steel electronics case (on-hand, full ocean depth)
PC-104 controller
400-48V dc (Vicor)
MOSFET and deadface switches, software controlled
Ground fault detection a la MARS
8-port 100baseT Ethernet switch
ROV-mateable
connectors
Electronics
ROV “fork” slots
Removable ballast
Fiberglass grating

19. Seafloor cable
Deploy using MBARI sled (need more capability in future)
Use ODI connectors
Use in-line electrical-optical converters at each end for 1.7 km long run (comms, precise time 1 pps)
1300 W-km

20. Small cable power delivery capacity
Source Wire Cross Wire Power
Voltage Gauge Section Resistance Capacity
VDC AWG mm2 Ohm km-1 Watt-km
Trade capability, distance, ROV/other deploy costs, cable cost, …

21. 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

22. Electrical-Optical Conversion
ROV mateable electro-optical connectors very expensive (~$30k), not likely for instrument connection
ROV mateable electrical connectors lower cost (~$6k) and will be used on MARS, VENUS, NEPTUNE and ALOHA-MARS
Fiber optic cables are required for high rate data transmission > 100m
Transmission distances up to 100 km
COTS ethernet electrical-optical converter available for operation in 10 kpsi oil (~$2k)

23. Power Budget - Watts Source Power 1200 Seafloor Loads
Infrastructure
Basic Sensors
Guest Sensors
Float Loads
Infrastructure
Battery Charging (or Winching)
Basic Sensors
Guest Sensors
Transmission and Conversion Loss
Total

24. Deck Frame Requires DP ship
Mooring winch
Trawl winch
Load transfers
Anchor first
Rail system – moves float and mooring cable in and out
Lays on fantail
Bolts to 2-ft pattern
Float and Ti post locked during prep

25. Deployment scenario
ROV deploys seafloor cable and secondary node with SIIM, 20 m clear of Love Point (done well before mooring deployment)
Deploy anchor, releases, and mooring using EOM cable winch
Attach MMP
Stop with top termination in-board of block (A-frame out)
Attach grip/chain to take load off termination, remove last section of cable (used as leader on the cable drum)
Attach inductive coupler to cable, connect
Attach swivel/Ti post to termination
Attach trawl wire to termination, laying through block, take strain
Guide into float slot, move float out, lock, release strain
Connect electronics, test
Attach acoustic release to 2-m nylon spring line on float ring
Attach acoustic release to 15-m nylon spring line attached to trawl wire
Move float and cable outboard on deployment frame with A-frame following
Take strain, swing out, lower to 3 m above bottom (pinger?)
Move to Love Point, drop
ROV moves bottom node closer, connects mooring, puts bottom SIIM on mooring, clears lowering line, inspects

26. Recovery scenario
ROV disconnects bottom SIIM and node, moves clear of mooring (recovers if necessary), attaches recovery line to float ring (detail?) if possible
Ship recovers line float (recovers anchor?), or uses acoustic release and snaps ring
Take strain and lift using trawl line (with nylon leaders, shackle through block?)
Swing float and post into deck frame and lock, release strain
Disconnect electronics
Connect trawl wire to Ti post ring
Disconnect Ti post from float, take strain, and swing out
Lift post high, attach grip below inductive power coupler and cable termination, chain, release strain
Disconnect swivel/post inductive power coupler from cable
Attach trawl winch to grip, pull up to block
Thread termination through block, attach to mooring winch leader
Take strain
Release trawl line from grip and remove latter
Pull in mooring cable unitl MMP shows; recover, continue
Recover releases (and anchor if the case)

27. General Questions
Interfaces in sensor network infrastructure – connectors, software, protocols, metadata, time stamping, geo-referencing, PMACS, DMAS, OCS, …
Standardization (e.g., SIIM connectors)
Costs
Development takes time, money – testing, and more money
Need ROVs, DP ships, and O&M structure
Reliability and cost/benefit study

28. Specific Questions/Issues ALOHA-MARS Mooring
Review all Interfaces
Evaluate Risk and mitigation
MMP IPC and docking – will test in January
Float system (new handling)
Electrical noise – more filtering, shielded TP,
Integration – will test in April at Seahurst
Contingency during deployment
Concerns
Project originally 3 years, now 5 years – extra cost
Extra cost for MBARI ROV, user fees? Other?
Reworking timeline and budget now

30. Junction Boxes Subsurface Float and on the 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

31. Observatory – Instrument Interface Examples

32. Other “SIIMs” Electro-optical conversion
Ethernet, metadata, power interface

33. Long term issues SENSORS and NEW APPROACHES
Sensor network infrastructure:
moorings/boreholes/distance/observatories
small diameter cables, laying
underwater ROV-mateable connectors, in-line convert
AUVs, rovers, moles - docks/tethers
Navigation and communications of mobile platforms
Work towards all robotic, reliable (cf. NEMO)
Need to bring in oil and military expertise
An overall architecture
Planning tools for users – the cost function
Research ship and ROV capabilities
Need to develop and gain EXPERIENCE

34. Other users
Jeff Nystuen – acoustic rain gage (and general ambient sound)
Peter Worcester – short VLA
Ken Smith – rover
Tom Sanford – HPIES
John Horne – fisheries sonar

35. Block Diagram ALOHA – Anchor J-box

36. Block Diagram: Float – Profiler

37. Junction Boxes Subsurface Float and on the Seafloor
4 User Connectors
Data Communications
10/100BaseT
RS-232/422 (?)
Power - ~200 W total
400 VDC (? no large or remote loads)
48 VDC
12 VDC (? probably more common)
Installed Sensor Suite
2 x CTDO2
Optics – transmissometer, fluorometer, CDOM, other (?)
ADCP (on Float)
Video on Float and Seafloor, still on profiler (goal)

38. 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

39. Science Instrument Interface
Present – for NEPTUNE, still based on Feasibility Report
Multi-pin ROV-mateable connector
400 V and 48 V (pins for each)
Ethernet 10/100baseT
Precision timing 1 microsecond
Needs Review, iteration with community

40. Junction box on seafloor and subsurface float

41. Block Diagram: Float – Profiler

42. Sensors Float – secondary node Float - SIIM Float Anchor - SIIM
ADCP
Attitude sensor
Inductive power coupler
Inductive modem
Video camera with lights
Float - SIIM
CTDO2 – Dual
Optical backscatter, two wavelengths, fluorometer
Float
Light, radio, ARGOS
Anchor - SIIM
CTDO2 – Dual
Optical backscatter, two wavelengths, fluorometer Anchor
Profiler
CTDO2
Optical backscatter, two wavelengths, fluorometer
2-d ACM