LIDAR used by flyby imaging service Topobird

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LIDAR used by flyby imaging service Topobird

• Ammon Christiansen

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Diagram

• GPS data also used     
• IMU (Inertial measurement unit) data also used
• PoS
• Manual grid points needed for high accuracy
• 500GB Data stored on plane

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Specs

• Down to 3m postings     
• Swath width (or field of view) up to 75     
• Scan rates to 70 Hz
• Multi-return intensity capture, up to 3 returns
   (RGB color that comes back)   
• Pulse rates to 45 kHz

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Comparison with Passive Vision

• Gyro-Stabilized Camera Mount the ADS40 camera is
  mounted on a gyro-stabilization base (Leica
  PAV30). The unit minimizes the angular motion of
  the camera while in flight. The actual motion of
  the camera is measured in flight by both the IMUs
  (Inertial Measurement Unit) and differential GPS
  units.
• POS A specially designed Position and
  Orientation System (POS) from Applanix
  Corporation collects data about the aircrafts
  trajectory and ensures successful ground
  processing. The raw ADS40 data is rectified using
  position and attitude data supplied by the POS.
• Storage Data is stored during flight on a
  half-terabyte mass memory unit which is then
  removed from the aircrafts computer and
  connected to a PC workstation for ground
  processing.
• IMU and GPSThe linear array camera and the LiDAR
  system require precise measurement of the
  position and orientation of their respective
  sensors. To achieve this, each system includes an
  embedded IMU and a GPS. While the GPS measures
  absolute position, the IMU measures relative
  position and orientation. The data collected by
  the IMUs, the GPS, and GPS ground stations is
  post-processed to achieve positional accuracy of
  30 cm and orientation accuracy of 20 arc seconds.
  The realized horizontal accuracy of the imagery
  is a function of the altitude of the plane.
• Ground ProcessingThe raw image data is rectified
  using position and attitude data for the sensor,
  supplied by the POS. This rectification process
  implicitly takes care of any discrepancies in the
  advance between lines caused by variations in the
  forward motion of the aircraft
• Mass StorageFor primary storage, DeLorme
  maintains a Storage Area Network (SAN) which
  includes two EMC Clarion arrays with a storage
  capacity of 35 TB. Both arrays are broken into
  logical units (LUNS) utilizing RAID5 with hot
  spares, which overlap read and write operations
  across multiple drives for increased performance
  and redundancy. The combination of RAID5 and hot
  spares means that even if several individual
  drives fail, the arrays keep working with no loss
  of data. The storage network switching fabric is
  comprised of two redundant Brocade Communications
  Systems Inc. Fiber Channel switches that support
  up to 2 GB/second throughput. A Qualstar Super
  AIT library with a capacity of 66 TB (132 tapes,
  each 500 GB) is connected directly to the SAN
  switching fabric for backup and archives. The
  Qualstar library has a combined native transfer
  rate of 432 GB/hr. Backups on the SAN are managed
  using BakBone Software Inc.'s NetVault software
  suite. The software does on-demand archives of
  TopoBird and other raster datasets at various
  stages of data processing. Two tape sets of each
  data archive are created, one of which is stored
  off-site at a disaster recovery facility while
  the other is housed in the DeLorme company data
  center.