1. Mooring Sensor Network for Ocean Observatories: Continuous, Adaptive Profiling Bruce M. Howe, Timothy McGinnis, Jason Gobat Applied Physics Laboratory, University of Washington Ocean Sciences Honolulu 24 February 2006

3. Introduction 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)

4. 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

5. Example: Fully loaded mooring (RFA 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?

6. 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 –2007-2008 on MARS in Monterey Bay, 900 m depth

7. FLOAT ASSEMBLY Instrument Package ADCP Float Ti Post ROV-serviceable instrument platform Secondary node

8. INSTRUMENT PACKAGE SIIM BB2F CTDO 2

9. SWIVEL Float Ti Post Oil Reservoir “D” Plate Mooring Cable Termination Primary Winding All Electrical EO Converter Electrical and Optical

10. MMP Secondary Winding S&K Engineering ~3 mm gap Efficiency ~65% 200 W transfer 10 kHz MMP electronics includes 24 V battery charging Concerns: –Biofouling –Robustness –Docking –Holding profiler in place during charging

11. Sensors BB2F

15. 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 Removable ballast ROV-mateable connectors Electronics ROV “fork” slots Fiberglass grating

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

17. MARS Node HydroGeo Borehole Seismo Borehol e MOBB Proposed Aloha Site UTM: 574520E, 4061663N 36 41’ 51.742”N 122 9’ 56.775”W ALOHA-MARS Mooring Location

18. Other users Jack Barth – upper ocean profiler Jeff Nystuen – ocean ambient sound Peter Worcester – vertical line array Ken Smith – bottom rover Tom Sanford, Doug Luther – HPIES John Horne – fisheries sonar Lee Freitag – acoustic modem/nav/comms

21. Mooring EOM Cable Diameter22 mm (0.865-in) Conductors 6 #18 AWG (4-power, 1-IM, 1-spare), 21  /km Fiber optic4 fibers, Corning SMF-28™ Fishbite ProtectionStainless steel braid, 70% coverage, 0.25 mm 304 SS wire Breaking Strength24,000 lbs Working Load4,000 lbs Elongation< 0.5% at working load (< 4 m for 4000 lbs and 800 m length)

22. Seafloor node Removable ballast ROV-mateable connectors Electronics ROV “fork” slots Fiberglass grating

23. Deployment scenario 1.ROV deploys seafloor cable and secondary node with SIIM, 20 m clear of Love Point (done well before mooring deployment) 2.Deploy anchor, releases, and mooring using EOM cable winch 3.Attach MMP 4.Stop with top termination in-board of block (A-frame out) 5.Attach grip/chain to take load off termination, remove last section of cable (used as leader on the cable drum) 6.Attach inductive coupler to cable, connect 7.Attach swivel/Ti post to termination 8.Attach trawl wire to termination, laying through block, take strain 9.Guide into float slot, move float out, lock, release strain 10.Connect electronics, test 11.Attach acoustic release to 2-m nylon spring line on float ring 12.Attach acoustic release to 15-m nylon spring line attached to trawl wire 13.Move float and cable outboard on deployment frame with A-frame following 14.Take strain, swing out, lower to 3 m above bottom (pinger?) 15.Move to Love Point, drop 16.ROV moves bottom node closer, connects mooring, puts bottom SIIM on mooring, clears lowering line, inspects

24. Recovery scenario 1.ROV disconnects bottom SIIM and node, moves clear of mooring (recovers if necessary), attaches recovery line to float ring (detail?) if possible 2.Ship recovers line float (recovers anchor?), or uses acoustic release and snaps ring 3.Take strain and lift using trawl line (with nylon leaders, shackle through block?) 4.Swing float and post into deck frame and lock, release strain 5.Disconnect electronics 6.Connect trawl wire to Ti post ring 7.Disconnect Ti post from float, take strain, and swing out 8.Lift post high, attach grip below inductive power coupler and cable termination, chain, release strain 9.Disconnect swivel/post inductive power coupler from cable 10.Attach trawl winch to grip, pull up to block 11.Thread termination through block, attach to mooring winch leader 12.Take strain 13.Release trawl line from grip and remove latter 14.Pull in mooring cable unitl MMP shows; recover, continue 15.Recover releases (and anchor if the case)

25. After Puget Sound tests will ask for other users to propose

26. 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

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

28. 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

29. Observatory – Instrument Interface Examples

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

31. 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

32. Block Diagram ALOHA – Anchor J-box

33. Block Diagram: Float – Profiler

34. 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 CTDO 2 – Optics – transmissometer, fluorometer, CDOM, other (?) – ADCP (on Float) – Video on Float and Seafloor, still on profiler (goal)

35. 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

36. 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

37. Junction box on seafloor and subsurface float

38. Block Diagram: Float – Profiler

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

40. Subsurface Float Instrument SIIM bays Guard rail ROV-positioning pins Swivel, 12-elect Termination (with E-O converter) Cable, 0.825-inch, 4 fiber 6 conductor, kevlar, fishbite ROV-mateable connectors Ti center post in slot Float, 3000 lbs buoyancy 2ndary J-box electronics (with IPC, SIM, ADCP, camera) SIIM

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

42. 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

43. 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 CTDO 2, FSI Acoustic Current Meter (ACM), WetLabs Red/Blue Backscatter and Fluorometer (BB2F) Lengthen, add sphere

44. 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

45. Small cable power delivery capacity Source Wire Cross Wire Power Voltage Gauge Section Resistance Capacity VDC AWG mm 2 Ohm km -1 Watt-km 2000 16 1.3 14 32500 2000 24 0.2 75 6087 1000 16 1.3 14 8125 1000 24 0.2 75 1522 400 16 1.3 14 1300 400 24 0.2 75 243 48 16 1.3 14 19 48 24 0.2 75 3 Trade capability, distance, ROV/other deploy costs, cable cost, …

46. 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

47. 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)

48. Power Budget - Watts Source Power1200 Seafloor Loads Infrastructure 40 Basic Sensors 25 Guest Sensors 200 Float Loads Infrastructure 30 Battery Charging (or Winching) 321 Basic Sensors 37 Guest Sensors 131 Transmission and Conversion Loss 415 Total1200

49. TypeElectro-optical-mechanical ManufacturerCortland Length1700 m (5580 ft) Diameter12.7 mm (0.50 inch) Minimum bend radius20 cm (8 inch) Conductors6 #16 AWG Resistance 4.7  /1000 ft/conductor Voltage Rating600 Vdc Fiber optic 4 SMF, 9/125/250  m, 100 kpsi Fiber Attenuation0.4 dB/km at 1310 nm Outer JacketPolyurethane, 0.060 inch, black Fishbite Protectionnone Breaking Strength2,100 lbs, Vectran Weight in air (130 lbs/1000 ft)725 lbs (1700 m) Weight in water (43 lbs/1000 ft)240 lbs (1700 m)

50. Inductive Power Coupler S&K Engineering ~3 mm gap Efficiency ~65% 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

56. User Requirements Current profiling for entire water column Near continuous in-situ profiling from near surface to seafloor with CTDO 2, ACM, bio- optics –> 1 profile 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

57. Outline Introduction and motivation Moorings ALOHA-MARS Mooring design Questions and issues Main point –we are developing ORION sensor network infrastructure

58. Introduction – 2 Sensor network infrastructure –everything between sensors and backbone nodes –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

59. 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

60. 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 with higher efficiency Multiple docks and profilers on a single mooring More sensors –Broadband hydrophone/transducer array, fixed, profiling –Bio-optics –Still/video –pCO 2

61. System schematic