Lidar Research Progress

1
Lidar Research Progress

• Space Dynamics Laboratory
• Utah State University
•  
• presented for the
• Wind Lidar Working Group
• Frisco, CO
• June 29 30, 2004
•  
•   S. Cornelsen, J. Cutts, C. Earl, D. Huish, T.
  Wilkerson
•   supported by IPO(NPOESS), NASA-Goddard and SDL
• Tom.Wilkerson_at_sdl.usu.edu

2
Outline

• Campaign history
• Multiple cloud layers
• Comparison of HOE lidar wind results with other
  methods
• Sonde wind variability (space/time averaging)
• HARLIE analysis using Hough transform
• Development of airborne lidar

3
Joint Lidar Measurement Campaigns

• March 1999 Logan, UT
  HOLO-1
• June 1999 Manchester, NH
  HOLO-2
• Sept./Oct. 2000 DoE ARM/SGP Site, OK
  WVIOP
• November 2001 Wallops Island, VA
  HARGLO-2
• April 2002 Ft. Bliss, TX (with
  D.R.I.) SERDP
• May/June 2002 DoE ARM/Homestead, OK
  IHOP-2002

Instruments HARLIE holographic scan lidar
SkyCam for cloud video imagery, AROL-2 profiler
for HOLO-1, and GLOW Doppler lidar for HARGLO-2
IHOP
4
Multi-Cloud Comparison
5
Harlie vs. Sonde
6
Sonde Wind Precision (IHOP 2002)
Mean 0.549 m/s
Conclusion Sondes provide a reasonable standard
for wind measurement.
7
Automatic HARLIE Analysis usingthe Hough
Transform

• The wave image is displayed with rotations as a
  function of scan angle, R(? )
• The equation for the matched sine curve is as
  follows

wind speed 1/A direction - B rotation offset - C
Rotations
R A sin (? B) C
Scan Angle

• The Hough Transform generates a surface
• C (A ,B) R - A sin (? B) for each (R, ? )
  pixel. Intensity of C depends on pixel
  brightness

• The surfaces intersect one another to form bright
  spots in the accumulation matrix in the (A ,B
  ,C) space. These spots identify the dominant
  wind speed and direction in the wave image.

8
Current Work on theHough Transform

• Improving the existing noise removal techniques
  and image pre-processing for better curve matches
• Increasing program functionality and versatility
  with added features

9
UVC-12 HOE Transceiver

• Hologram 12", 45?
• Weight 107 lbs.
• Length, diam.? 24"
• 3-Rod truss
• Convex secondary
• External PMTs
• Net optical eff. 5
• Timing belt drive

Stress

• Finite Element
• Analysis

Displacement
10
Outcomes

• Excellent teamwork with USU science/engineering
  students and our NASA-Goddard colleagues
• Continuing critical comparisons of HOE lidar wind
  results with other methods
• HOE lidar and cloud tracking suitable for 24/7
  operations
• HOE lidar supports calibration and validation for
  wind sensors
• Collaborative development of new instruments for
  lidar winds
• Design rugged UVC lidars for airborne Cal/Val
  Proteus, ER-2

11
Way Forward for SDL in the IPO/NPOESS Framework

• Continue detailed analysis of HOE lidar campaign
  data
• Compare with GLOW other instruments (IHOP,
  etc.)
• Eliminate occasional artifacts - e.g., in Hough
  transform
• Optimize UVC lidar designs and measurement
  scenarios for possible use in regional/global
  Cal/Val
• Tradeoffs in specifications and performance
• Composite material designs - SDL program
• Convertible UVC ? Cassegrain design
• Continue dialogue and collaboration with IPO
  NASA