New Technologies and Airborne LiDAR Bathymetry survey Techniques in European Environmental Coastal Mapping Projects

Transcription

1 New Technologies and Airborne LiDAR Bathymetry survey Techniques in European Environmental Coastal Mapping Projects Nigel Townsend, Fugro LADS Corporation SSSI, Spatial Information Day 03 August 2012 Adelaide, Australia

2 Introduction European Mapping Projects undertaking by Fugro LADS in 2012 Challenging requirements New LiDAR Technologies put in place Survey Operations to date Processing Techniques Results achieved Complementary LiDAR data sets

3 French Coastal Survey Areas Key Stakeholders Contracting Government Agency Service Hydrographique et Océanographique de la Marine (SHOM) BREST General Council of Finistère Planning Branch, Water, Environment and Housing, Department of Water Land Use Policies, QUIMPER Regional Council Provence Alpes Cotes d'azur (PACA) MARSEILLE

4 France Finistère (Brittany) Areas

5 France - Mediterranean Coast (PACA) Areas

6 France - Mediterranean Coast (PACA) Areas - cont

7 Italian Marine Protected Park Survey Areas

8 2012 ALB surveys in France Survey is for regional and national agencies for a number of applications for which a precise understanding of the coastal bathymetry is required. Products to support: benthic habitat mapping for biodiversity risk prevention including tsunami modelling flood inundation mapping coastline management including erosion and sand nourishment economic development for ports tourism and scientific research

9 Challenges to be overcome Finistère France Finistère Survey Areas Sea and Swell conditions Cloud Kelp Black rocks Bright sands Up to 13m tides, and tidal streams

10 Finistère survey area - kelp growth Image AAMP - PNMI Belts of himanthallia (distribution between 0 and 3 m) in summer

11 Finistère survey area - kelp growth Image AAMP - PNMI Belts of laminaria digitata (distribution between 0 and 5 m) in summer

12 Finistère survey area - kelp growth Image AAMP - PNMI Belts of laminaria hyperborea (distribution between 10 and 30 m) in summer

13 Finistère survey area - kelp growth Image AAMP - PNMI Seabed vegetation strata in summer

14 Finistère survey area - kelp growth Image AAMP - PNMI Impact kelp may prevent seabed coverage if surveyed too late in the season

15 Challenges to be overcome PACA France ATC restrictions Some areas could only be worked between 0600 and 0800 Airport Restrictions All but Nice would only open after 0800! Commercial Activity 3 major airports in the area Private aircraft movements Cannes, Hyeres and St Tropez very busy Tourism restrictions Restricted weekend and summer work on beaches Boat movements!! Noise restrictions before 0800 High Ground Military Restricitons

16 France Survey Strategy Certain areas in Finistère need to be surveyed in winter / spring prior to kelp growth, however the weather is not always suitable, spring tides are no go! Certain areas of PACA are impacted by commercial activities in summer months. May ATC / Airport issues to be resolved. Alternative areas are assigned and planned for each flight in the event that conditions are not suitable in the primary area ALB surveys have the benefit of the operational flexibility of an aircraft to freely move within and between survey areas to avoid unsuitable environmental conditions Very high importance placed on very shallow water areas by customer.

17 France Survey Strategy - Technology Need a solution that was capable of Surveying approximately 2500 sqkm in a 5 month period Achieve 30m in Atlantic and Mediterranean areas Can move between the French Atlantic and Mediterranean coasts at short notice Able to maintain coverage in very dark seabed areas adjacent to very bright areas and deal with Kelp issues Able to obtain high density coverage in the critical shallow water areas Solution was New LADS Mk 3 New Riegl Vq820g CASA Aircraft

18 France Survey Strategy Survey Plan Start Finistère areas during Winter prior to the commencement of Kelp growth, maximising tidal opportunities Survey PACA coastline during periods of bad weather in Finistère Complete PACA in early summer prior to onset of Tourists

19 2012 ALB surveys in France Images AAMP - PNMI Winter storms leave massive kelp deposits stranded on beaches

20 2012 ALB surveys in France Survey was commenced in winter to avoid a particular problem on the seabed of the Atlantic coast of thick kelp State of the field of kelp in February Image AAMP - PNMI

21 Bathy LiDAR Solution General Capability Designed for safe and efficient shallow water survey to IHO Standards High coverage rate to a maximum depth of 80m dependant on water clarity IHO Order 1a or 1b surveys and Order 2 for very efficient wide swath mode Applications: hydrography, coastal zone management, environmental, engineering, exploration LADS Mk 3

22 How Airborne LiDAR Bathymetry Works Scanned green beam, reflects from the sea surface and the seabed, and is detected by the green receiver. Green pulses from the sea surface are used to create a sea surface model Green pulses from the seabed, are used to determine the depth of water, relative to the sea surface model or measured from the ellipsoid

23 Fugro LADS Technical Philosophy Design Philosophy The cornerstones of Fugro LADS technical design philosophy are based on maximising the quality of the data collected, a focus on hydrographic survey for Nautical Charting and refreshing the technology through a continual upgrade process Data Quality The Fugro LADS systems have been designed with an emphasis on data quality. This is based on collecting signals with the highest quality signal to noise ratio by: High laser power Wide aperture optical receiver Automatic gain control Good Depth Performance

24 Technological Solutions - Fugro LADS Mk 3 General Coastal and Deep water Bathymetric LiDAR system Key System Enhancements 1. Reduced size and weight installable in aircraft of opportunity 2. Faster laser, The system has been launched initially with a 1.5 KHz laser with room for expansion, without loss of laser power (currently testing 2kHz upgrade) 3. Improved physical and optical design of the transmit and receive sides of the system, through improvements to the optical coatings on mirrors, lenses and windows to improve the reflectivity and transmission degrees cross-track and roll compensation. 5. The system has depth performance of 80 metres (clear water conditions). 6. Wider swath widths and resolutions LADS Mk 3

25 What s new with Fugro LADS Mk 3 LADS technology in an aircraft of opportunity, maintaining high laser power, wide aperture receiver and automatic gain control Improved performance including greater depth capability, higher altitude operations and very wide swaths Continual upgrade process has provided improved target detection, shallow water performance and seabed reflectivity Integration of other sensors: high density LiDAR and VNIR hyperspectral Use of PPP and ellipsoidal datums Port Stephens Golfe du Lion NW Shelf WA

26 Introducing a new capability High density shallow water ALB and topographic data New RIEGL VQ-820-G shallow water airborne Laser scanner has just been developed by RIEGL RIEGL system has been integrated with LADS Mk 3 system in the same aircraft Both systems operate at 532nm LADS system scans under the aircraft, RIEGL is angles 20 degrees aft Systems complement each other providing coverage on the coast and offshore to deep water (LADS) and very high density coverage in very shallow water and on the beach and coast (RIEGL) LADS Mk 3 and RIEGL VQ-820-G mounted in CASA 212

27 Simultaneous Operations LADS Mk 3 forward looking rectilinear scan pattern Riegl Vq 820g set up to be a rear looking orbital scan Both operated simultaneously, no interference was observed

28 RIEGL VQ-820-G system Operated in 138kHz mode ~ 1.5 point / sq m on the ground & in the water, at typical ALB survey speed / operating height Depth measurement up to 10 metres observed Laser footprint size ~ 0.6m at typical ALB operating height Operated at 42 degree fov, scan ~ 20 degrees aft

29 Data collection Operations Set to Work Conducted in Parma, Italy 18 Jan 31 Jan Initial trials in Italy, then in Brest France Finistère Deployment 11 Feb to 31May Neap tides quickly became critical Cloud was a constant problem 48 Successful survey flights, 21 aborted due to environmental conditions South Finistère area unable to be completed Operating Base in Brest, Finistère Region PACA Unable to be conducted simultaneously with Finistère Flown 11 May to 31 June Bouches de Rhone area not completed due to Turbidity Operating Base in Hyere, Var Region

30 LADS and RIEGL Coverage (Interim data) Zone North Finistère

31 LADS and RIEGL Coverage (Interim data) Zone West Finistère - Sein

32 LADS and RIEGL Coverage (Interim data) Zone PACA - Marseille

33 LADS and RIEGL Coverage (Interim data) Zone West Finistère

34 RIEGL Coverage (Interim data) Ile de Batz (island NW coast of Finistère)

35 LADS Coverage (Interim data) Ile de Batz (island NW coast of Finistère)

36 LADS and RIEGL Coverage (Interim data) Ile de Batz (island NW coast of Finistère)

37 Complimentary Data Sets - Breakwater LADS Data Riegl Data Merged Data

38 Complimentary Data Sets Ile de Sein (West Finistère) Riegl Vq 820 Coverage

39 Complimentary Data Sets Ile de Sein (West Finistère) LADS Mk3 - Coverage

40 Complimentary Data Sets Ile de Sein (West Finistère) Merged Data Coverage

41 Thank You Nigel Townsend Survey and Operations Manager - Fugro LADS Corporation n.townsend@fugrolads.com