NASA Technical Reports Server (NTRS) 20160006855: Lidar Sensor Performance in Closed-Loop Flight Testing of the Morpheus Rocket-Propelled Lander to a Lunar-Like Hazard Field

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by  NASA Technical Reports Server (NTRS)

Autonomous Landing Hazard Avoidance Technology (ALHAT)
Lidar Sensor Performance in Closed-
Loop Flight Testing of the Morpheus
Rocket-Propelled Lander to a Lunar-Like
Hazard Field
V. Eric Roback (presenting), Diego F. Pierrottet, Farzin Amzajerdian,
Bruce W. Barnes, Alexander E. Bulyshev, Glenn D. Hines, Larry B.
Petway, Paul F. Brewster, and Kevin S. Kempton
NASA-Langley Research Center, Hampton, VA
AIAA SciTech 2015, January 5 – 9, 2015
Gaylord Palms Hotel and Convention Center, Kissimmee, FL
ALHAT / Morpheus Lidars: SciTech 2015 Page1 1/5/2015
Planetary Landing: the Problem
Autonomous Landing Hazard Avoidance Technology (ALHAT)
• Existing state-of-art
Apollo 15
– Optical photos from
orbit (dependent on
favorable solar
illumination)
– Laser mapping from
orbit
– Low resolution hazard
detection
– Not real-time
– Restricts landing to
un-challenging lighting
& terrain
Brady, T., and S. Paschall, The Challenge of Safe Lunar Landing, Proc. of IEEE
Aerospace Conference, Big Sky, MT, March 6 – 13, 2010, pp. 1 – 14.
ALHAT / Morpheus Lidars: SciTech 2015 Page2 1/5/2015
ALHAT Solution
Autonomous Landing Hazard Avoidance Technology (ALHAT)
• GN&C & sensing
system
– Crewed or robotic
– Safe
– Precise (30m,1σ)
– Any ambient
lighting (use
lidars)
– Real-time DEM’s
• System goals
– Detect 30cm
hazards @1km
– 1 cm/s velocity
Hazard Detection
precision
& Precision
– 20 cm range
Guidance
precision
(1km to 100m)
ALHAT / Morpheus Lidars: SciTech 2015 Page3 1/5/2015
Lidars Installed on Morpheus
Navigation Doppler Flash Lidar EAluetcontroomnoiucss L anding FHlaazsahrd LAivdoaidra Snceen Tseocrh nHoeloagdy ((AFLLHSAHT))
Lidar (NDL) Chassis Box (LEB) Mounted to HDS 2-axis Gimbal
Laser Altimeter
NDL Optical
(LA)
Head
ALHAT / Morpheus Lidars: SciTech 2015 Page4 1/5/2015
Field Test Plan
Autonomous Landing Hazard Avoidance Technology (ALHAT)
5 flights in spring 2014:
3 open-loop &
NASA-Kennedy
2 closed-loop (1 at night ~ 10pm)
Shuttle Landing
Facility (SLF)
100 m
100 m
ALHAT / Morpheus Lidars: SciTech 2015 Page5 1/5/2015
Morpheus on Approach
Autonomous Landing Hazard Avoidance Technology (ALHAT)
Flash Lidar
Sensor Head
KSC Shuttle Landing Facility
Hazard Field (100m X 100m) Runway 15 Approach Lights
ALHAT / Morpheus Lidars: SciTech 2015 Page6 1/5/2015
Flash Lidar Specs
Autonomous Landing Hazard Avoidance Technology (ALHAT)
• Max range: 1.35km
Sensor Head
• # pixels: 128 x 128 = 16,384
(FLSH)
• Range precision: 8 cm (1σ)
– Allows 30cm hazard
Goal
detection@1km
Met
Electronics Box
• Size:
(LEB)
– FLSH: 11x13.5x13.25 inches
– LEB: 9.5x14.2x13 inches
• Weight:
– FLSH: *36 lbs
– LEB: *36 lbs
• Power: *450 Watts
* Dominated by terrestrial cooling system
ALHAT / Morpheus Lidars: SciTech 2015 Page7 1/5/2015
Flash Lidar Principles of Operation
Autonomous Landing Hazard Avoidance Technology (ALHAT)
Target 8ns pulse width
1° wide area
“freezes” target motion
beam
• Round-trip time of flight
– Range = speed of light x round-trip time of flight / 2
• 3-D images generated in real-time
– One image per laser shot
– 128 x 128 pixels (16,384) per image
– 20 images/sec output
ALHAT / Morpheus Lidars: SciTech 2015 Page8 1/5/2015
Flash Lidar Flight Data
Autonomous Landing Hazard Avoidance Technology (ALHAT)
Rock 1 Rock 2 Rock 1
(30cm)
Rock 2
Safe
(28cm)
Site
Hazard
Detection
Goals Met
Mission Elapsed Time (MET) = 45.641564 sec MET = 46.036214 sec
FF11 (Day) FF14 (Night ~ 10pm)
Rock 1
Rock 1
Rock 2
Rock 2
Range ~ 425m Range ~ 425m
ALHAT / Morpheus Lidars: SciTech 2015 Page9 1/5/2015
Rocket Plume Heat Effects on Flash Lidar
(scintillation)
Autonomous Landing Hazard Avoidance Technology (ALHAT)
FF11 (no issue) - FF12 (scintillation issues) -
3400 3400
MET = 44.141766 sec MET = 43.634655 sec
- 3000 nI - 3000 nI
t t
e e
n n
s s
ti ti
- 2600 y - 2600 y
( (
c c
o - o
u u
n n
- 2200 st - 2200 st
) )
- 1800 - 1800
Apply
wind
restrictions
for
future
flights
Safe Scintillation
Safe Site
Site Smearing
ALHAT / Morpheus Lidars: SciTech 2015 Page10 1/5/2015