Lidar Bathymetry – Technology and applications Oct 24rd, Netanya, Israel

Anders Ekelund

Managing Director

Airborne Hydrography AB

Airborne Hydrography AB World recognized supplier of Airborne LIDAR systems Products • HawkEye II for bathymetry • Chiroptera for shallow water • DragonEye for land Privately owned Airborne Hydrograpy was formed in a buyout from SAAB AB, and has accumulated more than 25 years of bathymetric LiDAR product development for SAAB and the Swedish Navy

Products

3

• HawkEye II – An airborne coastal survey system including deep water bathymetry and topographic LIDAR • Chiroptera – A shallow water coastal survey system including high density bathymetric LIDAR and high end topographic LIDAR • DragonEye – A high end pure topographic LIDAR system

LIDAR Bathymetry What’s the Attraction?

LiDAR Bathymetry is very cost efficient tool for large scale digital elevation modelling projects in the coastal zone Area coverage 10-50 km 2 hour per

The advantages of LIDAR bathymetry - Delivers data from both land and sea/floor - Fast progress (typical 10-50 Square km / hour) - No hazard for survey ships - Delivers the accuracy the authorities need

System design

Batmetric LIDAR • Typical end products – X,Y, Z point clouds (bathymetric and topographic) – Digital Elevation Models – Bathymetric charts, X,Y depths created from HawkEye data and tidal model – Shoreline definition – Image orthomosaics – Sea-bed reflectance product – Additional environmental products

Visingsö - Multibeam

Visingsö – Topographic HawkEye II data

Visingsö – Bathymetric HawkEye II data

Visingsö – Bathymetric HawkEye II data

Visingsö - Shoreline

Visingsö – Contour lines

Sea bed reflectance

Sample data

– Combined bathy – topo / Motala river mouth

Sample data Topo example – Industrial area

Sample data

– RGB colored point cloud

Sample data

– RGB colored point cloud

Sample data – River Topo / Bathy crossection

Sea-mine detection

• Dummy sea-mine – 70 cm diameter water filled boat fender, – painted in NATO green according to Ministry of Defence standard 00-23, Issue 3, may 30m 2001.

• Anchored on about 2,5 meters depth, at about 5,5 meters water depth.

Sea-mine detection

• The sea-mine is clearly visible in between the sea-surface and sea bed

Natural target at sea-floor

• Blue - Multibeam data • Green - LIDAR data • 0.8 meter high bolder found in both multibeam and LIDAR dataset

Man made target

• Blue - Multibeam data, • Green - LIDAR data • A one meter high cube placed on the sea-floor after the multibeam survey, discovered by the LIDAR

Sample data

– Boats in the harbour

Sample data -

2 meters dreging for new small boat harbour

Sample data

28 meter high object on the surface, 4,4 meters depth below What’s that?

A Fountain!

Summary

Modern bathymetric LIDAR • Simultanious capture of topo and bathy – Full waveform in both topo and bathy • Reasonable depth penetration – > 20 meter in clear waters k=0,1 – > 10 meters in less clear water k=0,2 • Capture of small targets – IHO special order objects detected to about 2/3 of the depth penetration • Excellent accuray – Bathymetry close to IHO special order (25 cm, 2 sigma, absolute)

Summary

Modern bathymetric LIDAR • • High data density – Typical • Topo > 10 points per square meter • Bathy > 1 point per square meter Easy installation – Sensor weight: 80 Kg – Power consumption: 15 Amp on the 28 VDC supply – One single turn key unit – Simple touch sceen operators interface

Summary

Modern bathymetric LIDAR • Can be used for a large number of appliacations – Coastal monitoring – Sea-Charting – Environmental monitoring – Oil and Gas Pipelines – Ports, harbours – River survey – Object (sea-mine detection) – Sea-bed classification – Military applications