https://registrano.com/events/dataweekend-07/

1. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
LiDAR技術與應用介紹
徐偉城
2013-10-05

2. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
Mapping
• Surface(ground, water) -> Airborne -> Spaceborne
• Sketch -> Analog -> Digital
• Digital Map
– Vector(Google Map地圖)
– Raster(Google Map衛星)
– 3D (Google Earth)
– …
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3. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
Elevations on Map
• Features(point, line, polygon)
– Color, Shadow, …
• Contour
• DTM(Digital Terrain Model, Digital Topography Model)
– DEM(Digital Elevation Model)
– DSM(Digital Surface Model)
– DBM(Digital Building Model)
– …
3

4. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
DTM for Digital Map
• DTM Quality
– Resolution(grid size)
– Precision
– Efficiency
• Methods of DTM
– Ground survey
– Stereo Image processing(Photogrammetry, Satellite)
– Synthetic Aperture Radar(SAR)
– LiDAR
• Airborne LiDAR provides high quality DTM
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5. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
DEM Comparison 5
5m grid1m grid

6. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
What is LiDAR
• LiDAR(Light Detection And Ranging, Lidar, 光達)
– Laser
– Range Finder
– Scanner
• Various type of LiDAR(Laser Scanner)
– Handheld： 3D Scanner
– Desk：3D Scanner & Printer
– Ground：Terrestrial LiDAR
– Mobile Mapping System(car, ship, …)
– UAV & Airborne LiDAR
– Satellite LiDAR
– *Atmosphere LiDAR
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7. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
LiDAR on Different Platforms
• Ground
• Car
• Ship
• UAV
• Airborne
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8. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
GPS Satellite
GPS Satellite
GPS X
Z
Y
IMU
Roll
Heading
Pitch
GPS Base Station
EDMI
Aircraft position
(lat , lon , el)
GPS
Aircraft orientation
(roll , pitch , heading)
IMU
Range and angle
EDMI
+
=
(E , N , h …)
Point cloud
Components of Airborne LiDAR
POS(position and
orientaion system)

9. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
Airborne LiDAR Characteristics
• Dense Point
– 1 pt/m2 to 10pt/m2 (sometimes higher)
– Multiple Returns with Intensities
– Full Waveform
• Accurate
– Penetrate Vegetation
– Vertical:5~15cm
– Horizontal:15~50cm (depend on fly height)
• High Efficiency
– High efficiency of data acquisition and processing
– Fewer GCPs
– Filtering without measuring
• Standard Data Format
– Las file (by ASPRS)

10. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
Different Point Density
density=10 pts/m2
density=1 pts/m2density=2 pts/m2
density=5 pts/m2

11. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
Data Acquisition
Trajectory
Strip adjustment
Aerial Photo
Combined Separation Satellite Lock/Elevation

12. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
Ground Points Filtering 12
Automatic classify and manual editing
Correct
Error (canopy)
Error (mountain ridge)

13. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
P.13
Flight lines Intensity Classes
Echos Elevation Waveform
Attributes of Point Cloud

14. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
DEM/DSM Products 14
DEM
DSM

15. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
DEM/DSM Products
DSM shaded reliefDEM shaded relief

16. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
Laser Footprint
Start Pulse
Range and Intensity
Measurement
Range1
Range2
Range3
Intensity 1
Intensity 3
Intensity 2
Discrete & Full Waveform LiDAR
LiDAR Returns(Leica, 2004,2010)
Full Waveform Digitizer
T1 ,
I1
Tn ,
In
Laser
– Wave length：1064 nm
– Power：2~4 watt
– Beam Divergence：0.25
~0.8 mrad
– Pulse Rate：50~200 kHz
– Classification：Class IV

17. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
Advantages of Full Waveform LiDAR 17
Discrete Las Full Waveform Las

18. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
空載光達產製數值高程模型技術
介紹

19. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
About LIDAR Technology Co. Ltd.
• Earth Observations
Spaceborne, Airborne & Terrestrial Data Acquisition
– Photogrammetry and LiDAR
– Hyper-spectrum and Thermal Image
• Geo-informations
Value-added products and applications
– Image Mapping and Interpretation
– Various DEM/DSM Products (90m, 30m, 10m, 5m, 1m, 0.1m)
– Historical Image and Topography Services
• Location Based Services
RS/GIS/GPS Development & Consultant Service
– 3D Building Model
– Disaster Applications
– Augmented Reality

20. LIDAR技術與應用介紹 © LIDAR Tech. Co.,Ltd., 2013
P.20
Thank you
TEL: 886-3-6589495
MAIL: ianhsu@lidar.com.tw
台北101大樓點雲剖面圖 台北101大樓模型(Google Earth)