KONGSBERG seafloor-mapping echosounders

Transcription

1 KONGSBERG seafloor-mapping echosounders Berit Horvei WORLD CLASS through people, technology and dedication

2 AGENDA Historical overview EM series Multibeam echosounder and Subbottom profiler Topside software. Seafloor Information System. SIS / 2 / 8-Dec-09

3 EM Applications xxx Marine Geology yyy Exclusive Economic Zones mapping (EEZ) Detailed Mapping (ROV, AUV applications) zzz Navigational Mapping Multibeam Echo Sounders Single Beam Echo Sounders Sediment Profilers Data Processing Software Operation Support: Route Surveying Operation Support: Dredging Port and Harbour Mapping of Rivers and Canals Surveying / 3 / 8-Dec-09

4 EM History Simrad s first Hydrographic Echos sounder, the EA 200 Simrad s first Multibeam - EM 100 Multibeam Echo sounder Development of the first deep water Multibeam system: EM 12 for IFREMER EM 3000 EM 300 EM 2000 First contracts for EM 120, 3. generation deepwater multibeam First EM 2000 used on C&C HUGIN AUV SBP 120 SubBottom Profiler delivered to SHOM EM 3002, Start of 4. generation EM 710 EM 122 / EM 302 EM 2040 / 4 / 8-Dec-09

5 1992 EM x EM x1.0 Backscatter (echo-strength) The footprint clearly depends on beam width and depth 50m Depths (sun-illuminated) the Revolution in Resolution Courtesy of CHS & JHC OMG/UNB / 5 / 8-Dec-09

6 Increased resolution ~25 cm high, 8 m long dunes developed in 170 m of water depth on the stoss sides of the larger bedforms Courtesy of CHS & JHC OMG/UNB / 6 / 8-Dec-09

7 Multibeam Echo Sounder product range Model Frequency Depth range Swath width EM khz 1-200m deg EM khz m 140 deg EM khz m 140 deg EM khz m 140 deg EM 2040* khz m deg * From 2010 / 7 / 8-Dec-09

8 Operational principles Common topside User interface Motion compensation Beam focusing Water column display & logging Dual swath FM pulses (EM 122, EM 302, EM 710, EM 2040) High density processing SVP correction / 8 / 8-Dec-09

9 Beams and transmission pattern Dual swath principle: Two transmissions with different frequencies per ping, which results in two swath along track per ping. Two (2) Transmit beams Effective beam footprint Twice the density compared to normal ping mode Receive beams Illustration of Mills Cross principle for multibeam transducers TX RX / 9 / 8-Dec-09

10 Beamforming - focusing Dynamically focused receive beams Beam focussing: A technique to obtain improved resolution inside the near field. The focal point is shifted as function of time & range. L Beamwidth Near Field With focusing / 10 / 8-Dec-09

11 Beamforming - focusing Without focusing: Inside the near field the beam is as wide as the physical size of the transducer (assume planar waves) L Beamwidth Near Field Object / 11 / 8-Dec-09

12 Focusing TX focusing Focusing in the nearfield on transmit is feasible by using three or eight separate transmit sectors per ping Focal points Footprint alongtrack / 12 / 8-Dec-09

13 Beams and transmission pattern Sector transmission with frequency coding and individual tilt control. Simultaneous transmission on all sectors. Roll, Pitch and Yaw Stabilisation This allows the system to be fully stabilized for yaw, roll and pitch. F1 F3 F5 F7 F8 F6 F4 F2 Courtesy of JHC OMG/UNB 8 sectors in deep water for EM302 & EM122, 3 sectors for EM710 / 13 / 8-Dec-09

14 EM 3002/710/302/122 common features Controllable swath width Full swath width Reduced swath width 254/400/432 soundings 254/400/432 soundings If the swath width is reduced on purpose or due to maxrange the full number of soundings is still produced inside the active swath. Result: A more dense pattern of soundings. / 14 / 8-Dec-09

15 FM, how to increase coverage CW. Increase output power cavitation Increase pulse length reduced range resolution FM Transmitted power controlled by the FM pulse length The FM sweep bandwidth used to control the range resolution 1000 m depth Sand [BSo= -30 db] B = 500 Hz Coverage: CW: 1.7 km FM: 2.6 km / 15 / 8-Dec-09

16 EM 2040 Design of the EM 2040: Separate transducers in titanium housings Three line arrays for transmitter Receive array scaled from EM 710 Gigabit Ethernet from Rx transducer to PU (to allow >100 khz range sampling rate) BSP 67B boards in PU for signal processing Dual system possible two Rx transducers but only one Tx needed / 16 / 8-Dec-09

17 EM2040 The true Wide Band Multibeam EM 2040 features Tx is pitch and yaw stabilized using three sectors Rx is roll stabilized Tx focused per sector, Rx dynamically focused Two swaths per ping available 200 dual system adds one Rx and one PU to single system 70 Watt max power at 48 Vdc (single system transducers) 18 kg dry weight max weight for 1 transducer 6000 m depth pressure rating standard (1 receiver) AUV version available 0.5x1, 1x1 & 1x2 models available (300 khz) / 17 / 8-Dec-09

18 EM2040 The true Wide Band Multibeam EM 2040 features Water column data Raw stave data Sidescan imagery data Backscatter data Equiangular, equidistant & high density modes Range resolution 1 -> 5 cm Automatic swath control FM mode / 18 / 8-Dec-09

19 / 19 / 8-Dec-09 Results EM 3002

20 Results EM 3002 Swedish Maritime Administration / 20 / 8-Dec-09

21 Results EM m depth Courtesy of Ifremer. L Atalante / 21 / 8-Dec-09

22 Results EM 302 Courtesy of NOAA- Okeanos Explorer m / 22 / 8-Dec-09

23 Results EM 122 Data courtesy of NAVAL OCEANOGRAPHIC OFFICE / 23 / 8-Dec-09

24 Results EM 122 Seabed image overlay Water depth m Data courtesy of NAVAL OCEANOGRAPHIC OFFICE / 24 / 8-Dec-09

25 Sub-bottom profilers SBP 120/300 Integrated with EM 120/122 or EM 302 Shared receiver array and preamplifier EM provides information for reliable, automatic guidance of the acquisition window Multiple receiver beams Beam opening angels from 3 x 3 (SBP 120) Beams are roll and pitch stabilized Heave compensated data Range resolution 1/3 millisecond Frequency range khz Penetration depending on depth and sediment properties / 25 / 8-Dec-09

26 SBP 120 example: Up to 250 ms penetration in 1000 m water depth 5 km 50 ms/div Data courtesy of NAVAL OCEANOGRAPHIC OFFICE / 26 / 8-Dec-09

27 MUD VULCANO SBP 120 / EM NAVAL OCEANOGRAPHIC OFFICE / 27 / 8-Dec-09

28 Seafloor Information System (SIS) All echosounders have SIS topside. Similar operation of all EM models PC hardware Windows XP Windows 7 / 28 / 8-Dec-09

29 Seafloor Information System (SIS) SIS can display full resolution terrain models, down to every single depth point. / 29 / 8-Dec-09

30 Seafloor Information System: RTK GPS-antenna Waterline Vertical datum Seafloor SIS provides strong support for RTK and geoid models in real time, in addition to observed and predicted tide Geoid Ellipsoid (WGS 84) / 30 / 8-Dec-09

31 Seafloor Information System (SIS) Datacleaning Uncleaned 3-d view 2-d view / 31 / 8-Dec-09 Cleaned

32 Seafloor Information System (SIS) Datacleaning Cleaned. Invalid points Uncleaned. Depth difference per cell / 32 / 8-Dec-09

33 SIS QA Neptune will be supported until SIS QA ready in 2010 (version 1.0)? SIS QA. Detect and correct any errors in the logged data from the echo sounder: Installation parameters Sound speed profiles Timing offsets Errors in the motion sensor data Position processing Further development will include tools for automatic analysis of the logged data / 33 / 8-Dec-09

34 SIS QA A common xyz-format KM is involved in a process we hope will lead to a common exchange format for xyz-data. X,Y,Z, Time, TPE, Beamno, Pingno, Flag, Calculations from range and angle will not be possible. One application can set the status flag and another application can read it. Applications can work on a common set of files. Work done in one application is persevered in the next application. / 34 / 8-Dec-09

35 SIS QA A common format for water column display A common format for displaying water column data is also being considered. Easier for 3. party software vendors to display and do high level processing on water column data. Hide the complexity of the processing and make it easier to use the results. / 35 / 8-Dec-09

36 Thank you for your attention WORLD CLASS through people, technology and dedication