Upload
dangnguyet
View
221
Download
0
Embed Size (px)
Citation preview
LIDAR WorkshopIPSRS – Commission 12-Jul-2007, Ljubliana, Slovenia
Arthur Rohrbach, Leica Geosystems, Switzerland
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland2
Presentation topics1. Basics of Airborne LIDAR Sensing Technology
2. Typical Applications (for Airborne LIDAR Technology)
3. System Components (of Airborne LIDAR Scanners)
4. Performance Parameters (for Airborne LIDAR Missions)
5. Operational Workflow (for Airborne LIDAR Operations)
6. Costs Parameters (for Airborne LIDAR Operations)
7. Practical Examples / Application Cases / Planning
8. Dual Airborne Sensor & LIDAR Scanner Systems
9. Outlook / Trends
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland3
Topic - 1
Basics of Airborne
LIDAR
Sensing Technology
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland4
Typical LIDAR technology implementationDevelop lat/lon/el of points on ground based on:§ Aircraft position (lat/long/H)§ Aircraft orientation (roll/pitch/heading)§ Scan angle
§ Round-trip propagation time of laserpulse
§ Atmospherics
Raw data recorded in air (System) &on ground (DGPS base station)
Recorded data post-processed on ground
Multiple-return intensity concerns attributes of the range measurement§ Time or distance§ Intensity
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland5
Basic Lidar Data “Layers”
Surface Mapping
Vegetation Classification
Ground Classification
Laser Point Data
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland6
Fundamentals of multiple-return technologyexample for 1- and 3-return scenarios
3rd return from ground
1st return from tree top
2nd return from branches1st (and only)
return from ground
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland7
Footprint
Return waveform is generated by all reflective
surfaces within the
laser footprint
Concept of multi-return intensity measurement
Multiple return intensity measurement is a natural extension of the measurement process
Systems featuring 1-5 return intensity measurement are available
Multiple ranges and associated intensities are generated as the laser pulse hits various levels in the forest canopy
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland8
Lase
r Fo
otpr
int
Start Pulse
Detector Signal Range 1
Range 2Range 3
Intensity 1 Intensity 3
Intensity 2
Multiple-return intensity analysis
Increases the possibility of classifying otherwise ambiguous data by lookingat the relationship between intensity and time variables, simultaneously
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland9
Start Pulse
Detector Signal Range 1
Range 2Range 3
Intensity 1 Intensity 3
Intensity 2
12
3
Time
Intensity
Intensity Profile
Multiple return intensity measurement methodologyEach return can be considered to represent a single pulse at a given range from the airborne vehicle
Each return pulse’s width and intensity can be plotted, referenced to some fixed point, say the start of the first return
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland10
Wavelengths of LiDAR Sensors
400 700 1000 1300 1600 1900 2200 2500
Piñon Pine
Cheatgrass
MapleSoil
AtmosphericTransmittance
0
0
0.6
1.0
Ref
lect
ance
Tran
smitt
ance
Near-IR Mid-IR
900 nm
FLI-MAP I/II
532 nm
LADS / SHOALS / HawkeyeBathymetric Systems
1047/1057/1064 nm
Optech ALTMLeica ALSTopeyeRiegl
1540 nm
TopoSys I/II
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland11
Topic - 2
Typical Applications
(for Airborne LIDAR Technology)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland12
Summary of applicationsbroad categories of applications
Modeling
Visualization
Change detection
Applications are limited only by
§ Sensor spatial resolution(typically to 10 points/m2 with 250+ m swath in fixed-wing aircraft)
§ Accuracy(typically 5-15 cm)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland13
Forestryaccurate ground profiling during leaf-on conditions
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland14
Forestrytree height and biomass estimation
Top View – Color Coded by elevation
Section view color coded by class
§ Brown = Ground
§ Green = Vegetation
§ Red = Model Key Points
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland15
Hydrologycoastal engineering
Image created using TerraScan
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland16
Hydrologyerosion studies
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland17
Hydrologyflood plain mapping and simulation
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland18
Mining and constructionaccurate volumetric calculations
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland19
Urban modelingbuilding extraction
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland20
Urban modelingbuilding extraction
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland21
Urban modelingdetailed “as-built” data
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland22
Urban modelinglarge areas with high level of detail
Flight parameters: altitude: 800m AGL, FOV: 35 degrees, scan rate: 29.4 Hz, pulse rate: 38 kHz, line spacing: 250m, number of lines: 18
Data parameters: area = 11.7 X 5 km (58.5 km2), number of points = 103 million, average density = 1.7 pts m2
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland23
Corridor mappingpower line position and vegetation clearance
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland24
Corridor mappingpower line position and vegetation clearance
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland25
Power line and infrastructure condition
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland26
Corridor mappinghighway corridor mapping
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland27
Airspace intrusion detectioncomparing bare earth + DSM
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland28
Data fusionsurface and intensity data
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland29
Topic - 3
Main System Components
(of Airborne LIDAR Scanners)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland30
Complete Airborne LIDAR Scanner ( Leica ALS50-II )including System Control & Flight Navigation Guidance
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland31
Data Sensing <> Scanner Head ( Leica ALS50-II )
New generation system provides greater point density, while increasing accuracy
In virtually all scenarios, ALS50-II with MPiA out-performs competing products
The ALS50-II provides a greater FOV and greater roll compensation range than competing products
The ALS50-II Scanner fits in small places like helicopter pods
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland32
Data Sensing <> Scanner Head ( Leica ALS50-II )Installation in Helicopter Pod
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland33
Data Control & Storage ( Leica ALS50-II )
3 Highly-flexible auxiliary sensorports (included)
§ Cameras
§ Thermal sensors
§ Hyperspectral sensors
§ Other external sensors / systemsAccesses common GPS/IMU data
Dedicated flight management system port (included)
§ Interface to a variety of externalFMS hardware
§ Potential for use as 4th sensor port
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland34
System Control & Navigation ( Leica ALS50-II )
Airborne-qualified operator interface – no laptops
Highly integrated flight management
Modularity with minimal external cabling
Single-drive recording of GPS/IMU and scanner data
All controls operated via GUI
§ Shutter
§ Laser output regulation
§ AGC settings
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland35
Real-time digital camera ( Leica ALS50-II )enhances editing
Real-time imagery to check for clouds / haze in line of sight
JPEG images recorded at preset interval for post flight terrain / cover verification
Images time-indexed and contain all georeferencing data
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland36
Mid-Format Camera System (Leica MidiPix 39MPx)product configuration
CH39 Camera Head (39 MP)
Lens (35, 60 or 100 mm)
CC105 Camera Controller
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland37
Digital Frame Camera Headtypical installations
Front-mount, dual CH39, non-isolated
Side-mount, CH39 + thermal sensor, isolated
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland38
Topic - 4
Performance Parameters
(for Airborne LIDAR Missions)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland39
Key performance parameters
• Performance of Optical System
• Accuracy of Components
• Performance of Laser
• Multiple Pulse capability (MPiA)
• Performance of IMU
• Performance of GPS
• Multiple Pulse capability (MPiA)
• Robustness / Calibration stability of system components
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland40
Large Optical ApertureTo “see” more
Detect smaller targets at higher altitude (e.g., power line profiling)
Fewer “drop outs” on low-reflectivity terrain features(e.g., asphalt pavement)
Fly in less-desirable atmospheric conditions (e.g., haze/smoke)
Preserves performance, even at today’s high pulse rates
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland41
Robust componentsTo assure continuous high performance
Laser features consistent pulse shape over wide range of pulse rates for high range accuracy/low range jitter
High-accuracy scan angle encoder preserves planimetric accuracy as altitude increases
Powerful galvanometer scanner
§ Allows use of large-aperture optics
§ Scans fast at any given FOV, allowing:§ Small along-track spacing in fixed wing aircraft
§ Balanced along-track and cross-track (very important when using high pulse rates and/or higher-speed aircraft)
§ Allows widest available FOV and greatest roll compensation range
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland42
High Laser PerformanceTo ensure clean pulses even at high pulse rates
Typical laser pulse ALS50-II laser pulse
33 kHz
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland43
High Laser Performance To ensure clean pulses even at high pulse rates
Typical laser pulse ALS50-II laser pulse
50 kHz
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland44
High Laser Performance To ensure clean pulses even at high pulse rates
Typical laser pulse ALS50-II laser pulse
100 kHz
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland45
High Laser PerformanceTo ensure clean pulses even at high pulse rates
Typical laser pulse ALS50-II laser pulse
150 kHz
?
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland46
MPiA – Multiple Pulse in the Air technologysignificant advancement in range measurement
> 1st Press release, 5-Oct-06: MPiA technology (Leica ALS50-II)
§ Allows rangefinding system to operate at double the pulse rateof current systems at any given altitude
§ - Uncomplicated upgrade path for existing systems (Leica ALS50)
> Significant performance benefits:
§ Double the data density at current swath
§ Double the swath at current density
§ Data acquisition cost savings approaching 50%
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland47
Fundamentals of MPiA technologysingle-pulse technology limits pulse rate
1 3 5
2 4
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland48
Fundamentals of MPiA technologyMPiA allows doubling of pulse rate
1 3
3
52
2
4
4 5
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland49
Gain in Pulse Rate & Accuracy (Leica ALS50-II-MPiA)Assuming a 5 cm GPS error
0
20000
40000
60000
80000
100000
120000
140000
160000
0 2000 4000 6000Flight Height (m)
Max
Pul
se R
epet
ition
Fre
quen
cy
(PR
F, H
z)
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
Acc
urac
y (m
, 1 s
igm
a @
40
FOV
)
PRF, 2PiAPRF, 1PiA xy, FOV edgexy, Nadirz, FOV edgez, Nadir
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland50
MPiA intensity image (Leica ALS50-II)2.5 points/m2 with 1000 m swath
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland51
MPiA surface model (Leica ALS50-II)low range noise for smoother surface models
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland52
MPiA intensity & surface model (Leica ALS50-II)Combined result from data @ 150 kHz pulse rate from 1250 m AGL
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland53
MPiA intensity image2.5 points/m2 with 1000 m swath
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland54
Ultra-high point density with superior accuracy
from an125-knotaircraft!
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland55
Topic - 5
Operational Workflow
(for Airborne LIDAR Operations)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland56
Airborne LIDAR Workflow - General comments
Workflow costs often follow a “5 – 10 - 85” pattern
§ 5% of costs for job / mission planning
§ 10% of costs for data acquisition
§ 85% of costs for data processing
The “85%” figure can vary substantially depending on nature
final of deliverables
§ Raw point cloud versus bare earth model
§ Feature collection required (building outlines, breaklines, etc.)
§ Level of quality checking
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland57
“Point cloud-based” workflow (Leica ALS50)based on TerraScan/TerraModeler
• DGPS processing (GrafNav)•Blended Solution(IPAS)
•point cloud generation•output formatting – LDI, LAS, ASCII•projection - WGS 84, UTM, state plane, etc.•datum (state plane only)
deliverables
Collection Processing
*.SCN raw scanner files
IPAS Pro / GrafNav ALS50 Post ProcessorPosition
and Attitude
file
TerraScan
MicroStation
•TIN/contour•control report
TerraModeller
boresightcalibration
Attune•tiling•coverage verification•outlier removal•bare earth•thinning•catenary generation•tree cell placement•building outlines
Flight EvaluationFlight Planning
FPES
FCMS
FPES•Check of Completeness•Quality Control•Project Management•Cost calculation•Reflight Planning
record DGPS base station data
Airborne Operations
record navigation data•GPS•IMUrecord scanner data•range•scan angle•intensity•timing infoflight management
•Flight guidance
•Sensor Release
•Flight Planning•Flight Optimization•Project Management•Cost estimation
DGPS groundstation files
GPS and IMU files
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland58
Flight Planning & Evaluation Software (Leica FPES)
Project ExplorerShows the project in a tree-like directory
Property viewDisplay of summarized data
Data view Display of detailed data
Graphic view
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland59
Flight Planning & Evaluation Software (Leica FPES)Multiple windows for different maps
Maps can have
§ Different Datum
§ Different zoom level
Example
§ Topographic map
§ Airspace map
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland60
Flight Planning & Evaluation Software (Leica FPES)Footprints on DTM
Footprint planning
§ AOI
§ Flight line
§ Event (Photo)
Footprint flight
§ Flight Line
§ Event (Photo)
AOI, hilly terrain
Single line, mountainous terrain
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland61
TerraSolid Processing Software
TerraScan§ Automatic and manual classification of
laser data (ground, vegetation, …) the key to all lidar data processing
§ Thinning of point cloud
§ 2D and 3D viewing of laser points
TerraModeller§ TIN/Contour generation
§ Import or manually add break lines
§ Cut/Fill calculations
§ Interface with PRO600 for feature extraction
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland62
“Grid-Based” workflow (Leica ALS50)based on VLS LIDAR Analyst
FPES
•point cloud generation•output formatting – LDI, LAS, ASCII•projection - WGS 84, UTM, state plane, etc.•datum (state plane only) - NGVD 29, NAVD 88•separation of first-, last-pulse point clouds•manual tiling
• Gridding• coverage verification• outlier removal• bare earth• thinning• catenary generation• tree cell placement• building outlines
Deliverables:Shape Files (e.g. buildings, trees
forrest areas)
LIDAR Analyst
ERDAS Imagine
or ArcGIS
•TIN/contour•control report
Collection ProcessingFlight EvaluationFlight Planning
• DGPS processing (GrafNav)•Blended Solution(IPAS)
*.SCN raw scanner files
IPAS Pro / GrafNavPosition
and attitude
fileFCMS
FPES•Check of completeness•Quality Control•Project Management•Cost calculation•Reflight Planning
record DGPS base station data
Airborne Operations
record navigation data•GPS•IMUrecord scanner data•range•scan angle•intensity•timing infoflight management
•Flight guidance
•Sensor Release
•Flight Planning•Flight Optimization•Project Management•Cost estimation
DGPS groundstation files
GPS and IMU files
ALS50 Post Processor
Leica Attuneboresightcalibration
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland63
Starting pointpoint cloud block loaded
All returns shown
Ortho point cloud view
Color coded by elevation
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland64
Comparison of rendered 1st returns to point cloudpoint cloud gridded
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland65
Comparison of rendered last returns to point cloudpoint cloud gridded
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland66
Bare earth extractionpoint cloud gridded
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland67
Building extractionpoint cloud gridded
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland68
Tree extractionpoint cloud gridded
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland69
Forest extractionpoint cloud gridded
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland70
LIDAR Processing Workflow (Leica ALS50 – MidiPix 39MPx)additional digital camera workflow items in amber
FPES
Mission Planningmodealtitudescan rateFOVflight speedflight linesflight heightlens FLshutter speedframe rate
record DGPS base station data
Airborne Operations
record position and attitude data•GPS•IMU•event marksrecord scanner data•range•scan angle•intensity•timing inforecord camera data•photo ID file•raw frames
extract position
and attitude
data
DGPS processing
trajectoryprocessing
•point cloud generation•output formatting – LDI, LAS, ASCII•projection - WGS 84, UTM, state plane, Swiss, TW 97, user-supplied•datum (state plane only) - NGVD 29, NAVD 88
•tiling•coverage verification•outlier removal•bare earth•thinning•catenary generation
deliverables
Ground Operations
Planning Collection Processing
real-time nav file
*.SCN raw scanner files
ALS50, FCMS, CamGUI
GrafNav IPAS Pro
ALS50 Post Processor
position and
attitude file
GPS1200
TerraScan
IPAS Pro
MicroStation
•TIN/contour•control report
TerraModeller
laser boresightcalibration
Attune
calculate exterior
orientations
EO fileIPAS CO
camera boresight, orthophoto generation
LPS
“LAS” file
orthophotosBayer
conversion
CDPP
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland71
Topic - 7
Practical Examples / Planning
of
Airborne LIDAR Applications
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland72
Application Cases
A. Corridor Mapping (power line, pipeline, road, railway)
B. Forestry Mapping / Monitoring (Resource Mngt)
C. Hydrology / River bed Mapping (Flood Modelling)
D. City Mapping (3D-Modelling, Telecom)
E. Costal Mapping (Erosion / Change Detection)
F. Basic DEM / DSM Generation (Key Reference forOrthophoto Mapping)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland73
A. Corridor Mapping - 1(power lines)
power line position and vegetation clearance
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland74
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland75
A. Corridor Mapping - 2(roads, railways)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland76
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland77
2. Forestry Mapping / Monitoring(Resource Management)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland78
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland79
3. Hydrology / River bed Mapping(Flood Modelling)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland80
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland81
4. City Mapping(3D-Modelling, Telecom)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland82
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland83
5. Costal Mapping(Erosion / Change Detection)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland84
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland85
6. Basic DEM / DSM Generation(Key Reference for Orthophoto Mapping)
< by color elevationby echo >
< by intensity (grey scale)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland86
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland87
Topic - 8
Dual Airborne Sensor Systems( ADS40 & ALS50 )
Dual LIDAR Scanner Systems( Airborne ALS50-II & Terrestrial HDS )
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland88
Dual - LIDAR - Systems(Airborne & Ground based)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland89
LIDAR Data Fusion
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland90
Dual - Airborne Sensing - Systems(Digital Sensor & LIDAR Scanner)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland91
Topic - 9
Outlook / Trendsin Digital Elevation Modeling
from an airborne LIDAR perspective
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland92
3 factors that will change how we use DEM datasystem performance, processing efficiency, data delivery
System performance
§ Affects “suitability for purpose”
§ Affects data acquisition cost
Processing efficiency will continue to be a major driver in cost per DEM point
Data delivery – the big enabler
§ Easy access
§ Broader market
Reduce cost per DEM point
New applications
Increased data demand
Economies of scale
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland93
System performance trendspoint density is up…
Over the past 10 years:
§ System pulse rates have increased 30x
§ Point spacing hasdecreased 5.5X
Major breakthroughs, such as Multiple Pulses in Air (MPiA) and enhanced laser technologies will continue to push data acquisition efficiency upward
How much detail is enough?
When does mapping become surveillance?
y = 7E-267e0.3115x
R2 = 0.9946
1000
10000
100000
1000000
1994 1996 1998 2000 2002 2004 2006 2008
Year
Puls
e R
ate
(Hz)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland94
System performance trendserror is down
Improvements in technology have steadily reduced error
§ Ranging errors
§ GPS errors improved, but are now the dominant error source at low altitude
Error levels are keeping pace with increased data density
BEWARE EXTRAPOLATION!!!
y = -0.0161x + 32.341R2 = 0.9986
0.0
0.1
0.2
0.3
1994 1996 1998 2000 2002 2004 2006 2008
Year
Acc
urac
y (m
)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland95
Processing efficiencywhat trend?
Processing has continued to take roughly the same time per flight hour
Gains have been mostly due to increased computing power
Big opportunity for improvement
After 10 years of LIDAR development, there are finally multiple 3rd-party competitors for filtering / editing SW
§ VLS
§ Q Coherent
§ TerraSolid
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland96
Data deliveryis it an image? or is it a surface? who delivers it?
Constraints on data delivery
§ 2D presentation versus 3D data
§ Data transmission method
Specialized firms will likely be the innovators
§ “owners” of data users in our industry(e.g., ESRI, Oracle)
§ “owners” of data users in other markets(e.g., Google, Microsoft)
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland97
Conclusions
Cost per DEM point continues to decrease
Quality of DEM data continues to increase (at least for now)
Opportunities for standardization, establishing “best practices” exist, particularly in the areas of
§ GPS planning standards (SV quantity, PDOP, base station practices)
§ Point density requirements derived from mapping standards
§ Quality Control methodologies and/or reporting
Increases in processing efficiency are a big opportunity
New data delivery methods could enable data use in broader markets
ISPRS, Lidar-W/S, Ljubliana, 2-Jul-07 / Arthur Rohrbach, Leica, Switzerland98
Thank you