Fully Autonomous Aircraft Navigation using Airborne LiDAR and Terrain Elevation Databases

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Fully Autonomous Aircraft Navigation using
Airborne LiDAR and Terrain Elevation Databases

• Jacob Campbell
• Ph.D. Research Proposal
• Advisors
• Maarten Uijt de Haag, Ph.D. Frank van Graas,
  Ph.D.
• Committee Members
• Chris Bartone, Ph.D. Martin Mohlenkamp, Ph. D.
  James Rankin, Ph.D.
• October 6, 2003
• Ohio University

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Overview

• Challenges for LiDAR Technology
• Proposed Tasks
• LiDAR Position Attitude
• All Weather Operation
• Practical Work (LiDAR DC-3 Installation)
• Research Schedule
• 5 Specific Goals
• Topic Details
• Terrain Navigation Background
• LiDAR System Description
• LiDAR Application Examples
• Case Study Reno Flight Tests

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Airborne LiDAR Technology
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Scanning Laser Concept
From RIEGL, Laser Measurement Systems
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Airborne LiDAR Parameters
0.13 m _at_ 400 m AGL 4 m _at_ 12000 m AGL
10 m _at_ 200 kts
200 m _at_ 400 m AGL
PRF 33,333 Hz Scan Angle 15 deg NdYAG w/ ?
1.064?m
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Disparity Calculations
where N number of samples to accumulate
Sum of Squares,
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Pierce-point and Range via Ray-tracing
A
B
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Search Space
Position, Orientation and LiDAR Scan Angle at ti
Add Offsets to Position and Orientation
Ray Trace to Find Range to Terrain Pierce Point
rdb(ti)
pdisparity(ti)
rlaser(ti)
Example of a Horizontal Position Search Space Plot
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Results-1
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Results - 2
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Worse Than Expected Performance?

• Vertical Error Disparities

0.14 m RMS value 0-20 sec., 1.26 m RMS 20-100 sec
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All Weather Navigation

• Define All Weather
• Currently looking into worst case weather
  conditions at airports
• Define the maximum ranges (Which are application
  dependent)
• Weather Attenuation
• Laser Technology

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Research Schedule
W 04
F 03
All Weather Laser Ranger Work
? 1
X
Installation Efforts of Laser Scanner and
Data Collection Equipment on DC-3
? 2
? 2
Create LiDAR Data Processing Tools
? 3
X
Su 04
Sp 04
Assess Measurement Solution using NASA
Dryden DC-8 Data
? 4
? 4
Measurement Confidence Bound Research
? 5
? 5
W 05
F 04
Measurement cont.
? 4
X
Navigation Solution Research
? 6
X
Su 05
Sp 05
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5 Dissertation Goals

• Determine LiDAR measurement (position and
  attitude) accuracies
• Develop statistical confidence bounds on these
  measurements which are based on knowledge gained
  from the terrain database.
• Implement a navigation solution algorithm
• Establish parameters for an all weather laser
  ranger.
• Gain practical knowledge through the installation
  of a LiDAR sensor on OU-AECs DC-3.

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Terrain Navigation Background

• Terrain Contour Matching (TERCOM)
• Terrain profile correlation
• Sandia Terrain-Aided Inertial Navigation (SITAN)
• Terrain slope information used as input to a
  Kalman filter with INS, radar altimeter, and baro
  altimeter
• Parallel SITAN
• Multiple parallel Kalman filter banks
• TERPROM
• Terrain profile based

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Applications Examples
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Case Study Reno Flight Tests

• Terrain Database
• 10 by 18 km of 1.5 m nominally post spaced data
  collected by NGS
• Sensor
• Optech ALTM
• 1233
• Goal
• Demonstrate
• position and
• attitude solution

-Picture of Reno Airport Created from LiDAR
Data visualized in QTviewer
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ALTM on DC-8Architecture
7/17/03
RadAlt (DC-8 data system)
INS data (DC-8 SATCOM)
Cabin Rack
115VAC 60Hz
400 Hz Power (Pilot Switch)
RS-232
3
GPS
KVM
DIME Computer
R
L
WxR R/T
A429
L
WxR Pedestal
RS-232
L
115VAC 60Hz
WxR Antenna
C
A453
L
C
2
Ethernet
A429
A429 (ADC, GPS)
RS-232
GPS
DC-8 VCR
Cargo Bay Rack
DC-8 video
ALTM Remote Control and GPS
Video
ALTM Control Rack
CRT
CRT
28VDC _at_ 35A Power Supply
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NASA DC-8 Flight Test-Edwards AFB August 4, 2003
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Data Collected

• Approaches into Reno Airport
• Scan Data Collected at Eye Safe Altitudes