Waveform LiDAR - More Than XYZ Point Clouds
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The document discusses advancements in waveform LiDAR technology by Riegl Laser Measurement Systems, emphasizing its capabilities beyond traditional point clouds through full waveform analysis and processing methods. It presents various applications and comparisons of waveform data including calibrated amplitude and reflectance attributes, along with features such as pulse shape deviation for improved measurement reliability. The document also highlights integration plans with a flying-camera system and provides contact details for further inquiries.
Waveform LiDAR - More Than XYZ Point Clouds
- 1. CONNECT. TRANSFORM. AUTOMATE. WAVEFORM LIDAR - More than x,y,z pointclouds Christian Sevcik, RIEGL Laser Measurement Systems GmbH Manager, Strategic Software Alliances
- 2. CONNECT. TRANSFORM. AUTOMATE. Terrestrial Airborne Mobile Unmanned Industrial
- 3. CONNECT. TRANSFORM. AUTOMATE. Dr. Andreas Ullrich, CTO Dr. Johannes Riegl, CEO
- 6. LIDAR technologies (Laser RADAR, ALS/TLS/MLS ) CW Phase-‐Based LIDAR Pulsed Time-‐Of-‐Flight LIDAR Discrete Return LIDAR Echo-‐DigiFzing LIDAR Off-‐Line Full Waveform Analysis On-‐Line Waveform Processing
- 7. Time of flight - multitarget t0 …Starttime Ps …pulse sent Pr …pulse reflected t1 …Endtime Pe …pulse echo Pr1…pulse reflected 1 Pr2…pulse reflected 2 Pr3…pulse reflected 3 Pr4…pulse reflected 4
- 8. Why waveforms ? Plane target, nearly orthogonal measurement angle Plane target, oblique measurement angle Multiple reflection of the laser pulse (spatially distributed targets) Target Laser pulse Echo Multiple reflection of the laser pulse (equal distance targets) Multiple reflection of the laser pulse (vertically stacked targets)
- 11. Waveform vs Discrete Return clear separation of target returns FWA: perfect result OWP: perfect result DRS: accurate results merging of target returns FWA: perfect result OWP: satisfying result DRS: range error on second target severe merging of target returns FWA: nearly perfect result OWP: just one target, but detection of pulse shape deviation DRS: just one target, no hint to second target FWA .. Full Waveform Analysis OWP .. Online Waveform Processing DRS .. Discrete Return System DRS
- 13. External Attributes Native AttributesGeometry What‘s in the Pointcloud? Waveform pointcloud Basic pointcloud
- 14. Calibrated amplitude Grey scale encoding of point cloud: • calibrated amplitude • 0 dB to 50 dB above detection threshold Brightness decreases from near objects to far objects.
- 15. Reflectance Grey scale encoding of point cloud: • relative reflectance of target • -20 dB to 3 dB with respect to diffusely reflecting white target Brightness independent of object distance. Targets with a reflectance above 3 dB are shown in white, targets below -20 dB are black.
- 16. Comparison intensity / reflectance Range dependent intensity readingRange independent reflectance reading Low High
- 17. Pulse shape deviation ! deviation of echo pulse shape from emitted pulse shape δ, provided additional to target range and amplitude ! Similarity of echo pulse (Pe) to instrument-specific reference pulse (Pr) ! Measure for reliability of range result N … the number of digital samples si … digiFzed echo samples pi … system response samples Pe Pulse shape deviation Pr1Pr2Pr3 Pr ‘best fit‘
- 18. Pulse shape deviation All pointsPoints filtered by pulse shape deviationFiltered pointcloud
- 19. Pulse shape deviation All points pulse shape deviation > 20 marked yellow
- 20. WAVEFORM LIDAR IN FME
- 21. RDB Reader ! Available since FME 2013 ! Supports Terrestrial, Mobile and Airborne RIEGL scan projects (.rsp, .rpp)
- 22. RDB Reader
- 23. Workbench sample Calculate mean tree height 1. Read in RDB and reproject 2. Normalize height 3. Calculate Pointcloud statistics 4. Create 3D Tiles 5. Send to Shape File
- 24. Workbench sample Calculate mean tree height Filter by pulse shape deviation
- 25. Workbench sample Calculate mean tree height Raw LIDAR Terrain model Mean Tree Height
- 26. • Additional pointcloud attributes • Range independent intensity: REFLECTANCE • Quality indicators for every single point • … and it is available in FME Summary
- 27. Weight: 3.6kg Scan rate: 500000 meas/s Field of View: 330° Planned integration of RIEGL VUX®-1 with Flying-Cam SARAH 3.0 © Latest developments
- 28. Thank You! ! Questions? ! For more information: ! Christian Sevcik, csevcik@riegl.com ! RIEGL Laser Measurement Systems GmbH ! www.riegl.com ! www.riegllidar.com ! : RieglLMS CONNECT. TRANSFORM. AUTOMATE.