BARNARD MICROSYSTEMS LIMITED

helping you keep an eye on things...

   
     
Home / unmanned air systems / payload I / lidar scan
 

 

   
Home | introduction | circuit design software | unmanned air systems | contact | what's new | site info
 
 

 

   

unmanned air ...

features 
issues 
applications I 
applications II 
geological survey 
oil leakage 
engines 
avionics 
airframes 
payload I 
payload II 
data processing 
milestones 
calendar 
reference 
 

payload I

UV sensors 
DSLR camera 
mid size camera 
compact camera 
stereo 
line scan 
multi-spectral 
hyperspectral 
thermal imaging 
lidar scan 
 

Scanning LIDAR

In a LIDAR system, a LASER beam is used in place of a  microwave beam, to detect the distance to a target.

Scanning LIDAR is used to:

  • detect the distance to obstacles in front of the UAV, to help with collision avoidance
  • generate data for a Digital Elevation Map of the area under the UAV
  • detect the presence and height of trees, as shown in the plot above

See also altimeters

 

 

 

 

 


 

Scanning eye safe laser LIDAR

- from www.sickusa.com

Sick LMS 211-30206

value

units

scanning angle

100

degrees

resolution / accuracy (+/-) / range with 10% reflectivity

10 / 35 / 30

mm / mm / m

angular resolution (selectable)

0.25 / 0.5 / 1

degrees

response time

53 / 26 / 13

mS

weight

9

Kg

return to top

Example of LIDAR scan showing tree height

Three LIDAR scans, showing trees and the ground level, from http://denali.gsfc.nasa.gov/research/laser/slicer/slicer.html

return to top

LiteMapper LIDAR

From www.litemapper.com

The LiteMapper system is a fully integrate sensor package for highly accurate 3D measurements of the Earth's surface. It includes

  • High-resolution Laserscanner (scanning Lidar)
  • High-accuracy Position and Orientation sensor system
  • Control and data logging unit
  • Flight guidance system
  • Software for mission planning, system operation, data registration, geocoding, and processing
  • Optional Digital Video system
  • Optional Digital Camera system

All components are engineered for operation on airborne platforms. The compact and lightweight design and low power requirements make the LiteMapper system ideal for small survey aircraft and helicopters. A high degree of automation and tight integration with the flight guidance system make it easy to operate. A dedicated lidar operator is often not required.

Among LiteMappers special features are:

  • full return waveform digitization (LiteMapper 5600) for accurate and detailled mapping of vertical structures (vegetation, infrastructure), improved reliability and accuracy of elevation measurements
  • uniqe ability to collect true surface color information with each lidar measurement (LiteMapper 2800). Natural color and CIR true-ortho images at the lidar point density are available without additional processing.
  • superior range resolution and measurement accuracy

LiteMapper 5600

Versatile mid-altitude system for high-resolution topographic and corridor mapping with fixed-wing aircraft and helicopters with full waveform digitization

Specifications:

  • Range: up to 1500 m
  • Range resolution: 15 mm
  • Pulse repetition frequency: up to 200 kHz
  • Scan pattern: parallel scan lines, near-equidistant samples
  • Scan angle (fixed): ±22.5° (up to ±30° at reduced range)
  • Scan rate: variable, up to 160 scans/sec
  • Effective measurement rate: up to 133000 measurements/sec (@ ±30° FOV)
  • Full waveform digitization
  • " Unlimited" number of returns and intensities with each shot
  • Target separation down to 0.5 m within single shot
  • Detection of low ground vegetation down to 0.2 m height
  • eye-safe (laser class 1)
  • Sensor head dimensions: 560 x 200 x 210 mm , approx. 30 kg
  • typical accuracy (flat target, 850 m AGL): 0.04 m vertical, 0.12 m horizontal (RMSE, excluding GPS errors)
  • typical survey parameters (@ 120 kts flying speed):

Altitude above ground

Swath width

Point density / spacing

130 m (@40 kn, ±30°)

150 m

42 points per sqm / 0.15 m x 0.15 m

400 m (@±30°)

462 m

5 points per sqm / 0.46 m x 0.46 m

600 m (@±30°)

690 m

3 points per sqm / 0.57 m x 0.57 m

1000 m (@±22.5°)

1155 m

1 point per sqm / 1.04 m x 1.04 m

Waveform profile through forest area. From www.litemapper.com.

" Accumulated waveform" (© GeoLas Consulting). From www.litemapper.com.

return to top


© Barnard Microsystems Limited 2006 - 2008