APPLICATION OF DIGITAL PHOTOGRAMMETRY FROM UAV INTEGRATED BY TERRESTRIAL LASER

SCANNING TO DISASTER MANAGEMENT

BRCKO FLOODING CASE STUDY (BOSNIA HERZEGOVINA)

1 - Department of Engineering and Architecture, University of Trieste, Italy2 - Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS) Trieste, Italy3 - GeoSNav Laboratory, University of Trieste, Italy

F. Cescutti1, F. Coren2, A. Pavan2, R. Cefalo3, A. Calliari3

The Brcko District

The Brčko District (Bosnia andHerzegovina) is a neutral, self-governing administrative unit, underthe sovereignty of Bosnia andHerzegovina.

Covered area: 493Km2

Total Population: 93000

Floodings occurred May 2014

In May 2014 a the torrential rainfall occoured in the Balkan regioncaused extensive flood damages and activated thousands of landslidesdevastating roads, bridges, buildings and other infrastructures.Current scientific information about the subsurface is essential for thereconstruction activities.

Minesfield problems

Survey target

TOPOGRAPHIC 3D RECONSTRUCION LANDSLIDE PATTERN RECOGNITION AND

DELIMITATION

TOPOGRAPHY SUPPORT TO THE GEOPHYSICAL SURVEYS (SEISMIC AND GEOELECTRIC)

ORTHOPHOTO PLANE GENERATION RECOGNITION OF THE MORPHOLOGICAL LANDSLIDE

ELEMENTS

EVALUATION OF DAMAGES

The Team and the Financing

PROJECT LEADERS Professor Snezana Komatina (University of Belgrade,Serbia)-

Team Leader Dr. Koya Suto, Dr Jun Sugawara (Terra Australis Geophysica,

Australia) Professor Milovan Urosevic (Curtin University, Australia) Dr. Franco Coren (OGS, Italy) Professor Alireza Malehmir (Uppsala University, Sweden)

FINANCIAL SUPPORT SEG – SOCIETY OF EXPLORATION GEOPHYSICISTS

GEOPHYSICIST WITHOUT BORDERS

Systems

LASER SCANNER RIEGL VZ400

Integrated GPS receiver (L1)

Internal 32Gbytes flash memory

Range 350m (speed mode)

Range 600m (long range mode)

122000 meas/sec (speed mode)

42000 meas/sec (long range mode)

Systems

Drone class 650

Flight control board: APM 2.6 with GPS ublox neo-7m

Battery: LiPo 4s 4000mha

Flight time: 15min @ max TOW

TOW: 2500g with 2 cameras

Systems

Drone class 250

Flight control board: NAZE32 (NO GPS)

Battery: Lipo 3s 1500mha

First person view sistem (downlink video)

Flight time: 5-6min @ max TOW

TOW: 650g with 1 camera

Systems

Canon Powershot A2200 (modified)

Fixed focal lenght 5.00mm

CHDK firmware, UAV Exposure Control Script

Sensor: 14.1 Mpix, 1/2.3" CCD

Power: lithium-ion battery

Weight: 110g

Systems

THE DRONE CLASS 650 WAS OUR FIRST CHOICE, DUE TO THE HIGH PERFORMANCE AND (APPARENTLY) THE RELIABILITY OF THIS SYSTEM

DUE TO A ELECTRONIC FAILURE AFTER A FIRST TEST MISSION WE HAD TO WITHDRAW THIS SYSTEM IN FAVOUR OF OUR CLASS 250 DRONE

THEREFORE ALL THE MISSIONS HAVE BEEN ACCOPLISHED WITH THE 250 CLASS SYSTEM THIS PRINCIPALLY IMPLIED THAT WE HAD TO FLY VISUALLY IN

FIRST PERSON VIEW (VIDEOTRASMITTING TO THE GROUND)

NO AUTONOMOUS FLIGHT WAS POSSIBLE

Processing steps

LASER SCAN DATA GEOLOCATION BASED ON GROUND CONTROL POINTS

PHOTOGRAMMETRIC PROCESSING OF DRONE IMAGES

GEOLOCATION OF DIGITAL ELEVATION (SURFACE) MODEL DERIVED BY DRONE IMAGES

MATCHING BETWEEN LASER SCAN DATA AND DTM DERIVED FROM DRONE DATA

GROUND CLASSIFICATION OF THE INTEGRATED DATASET

Locations

Locations – First landslide

Sparse Point Cloud: 192.418 points

Locations – First landslide

Dense Point Cloud: 39.744.861 points

Locations – First landslide

Mesh: 2.565.637 faces

Locations – First landslide

Mesh texturized

Locations – First landslide

Digital Elevation Model

Camera center position and photogrammetric point density

# overlap

Ground control points Analysis

Locations – Second landslide

Sparse Point Cloud: 86.941 points

Locations – Second landslide

Dense Point Cloud: 20.959.908 points

Locations – Second landslide

Mesh: 4.191.972 faces

Locations – Second landslide

Mesh texturized

Locations – Second landslide

Digital Elevation Model

Camera center position and photogrammetric point density

# overlap

Ground control points Analysis

Laser scanner data

Laser scanner data

Laser scanner data

Laser scanner and photogrammetric data merging

Laser scanner points : WHITE

Structure from motion (Photo): COLOURED

Laser scanner and photogrammetric data merging

Laser scanner points : WHITE

Structure from motion (Photo): COLOURED

Laser scanner and photogrammetric data merging

Laser scanner points : WHITE

Structure from motion (Photo): COLOURED

RESULTS

Landslide delimitation

DETACHMENT LIMIT

ACCUMULATION AREAFirst landslide

Landslide delimitation

DETACHMENT LIMIT

ACCUMULATION AREA

Second landslide

RESULTS

EVEN THOUGH WE OPERATED WITH A SMALL DRONE WITHOUT GPS AIDED FLIGHT, THE MISSION HAS BEEN COMPLETELY ACCOMPLISHED WITH THE REQUESTED ACCURACY

THE INTEGRATION BETWEEN LASER SCAN DATA (FROM THE GROUND) AND DRONE PHOTOS, PRODUCED A DIGITAL TERRAIN MODEL WITH HIGH RESOLUTION AND ACCURACY

THE CAPABILITY OF THE DRONE TO FLY OVER MINED AREAS HAS BEEN DEMONSTRATED

THANKS

FOR YOUR ATTENTION!