Precision Navigation for Small Unattended Aerial Vehicles

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Precision Navigation for Small Unattended Aerial
Vehicles
McNair Scholars Program

• Drake Miller
• Faculty Mentor Dr. Gary Gear

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Overview

• Research Thrust
• Unattended Aerial Vehicle (UAV) Background
• Full Scope of Research
• Future Work

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Research Thrust

• Embry-Riddle UAV Initiative
• Multi-year plan
• Implement enabling technology
• Distributed Flight Control System (DFCS)
• Focal point for research projects
• CE, EE, CS, AE
• Primary target low cost
• Industrial/educational applications
• UAV Helicopter - 20k

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Background

• Started Unmanned Aerial Vehicle
• NASA coined Unattended
• Meaning no pilot or remote control
• Major problem with UAVs today
• Built around one centralized computer
• Complex design
• Error prone
• Not easily adaptable
• Lacks robustness

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Full Scope of Research

• Main Objective
• Define a suitable Inertial Navigation System for
  our UAV
• Primary criteria
• High short-term performance
• /- 1 or better over 10 s
• /- 10 ft in pos. over 10s
• Inexpensive
• Lightweight
• Limited useable load
• Low power consumption
• Limited onboard power

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Tracking UAV Movement

• Instrument Inertial Measuring Unit (IMU)
• Sensor cluster and sampling circuits
• Navigation computer
• Performs filtering and navigation calculations
• Strapdown Inertial Navigation System
• Rigidly fixed to body no gimbals
• Combines IMU and navigation computer
• Attitude Heading Reference System (AHRS)

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Inertial Measuring Unit

• Orthogonal sensor cluster
• Rate gyros and accelerometers
• MEMS sensors satisfy criteria

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Navigation Computer

• Data filtering
• Kalman filter
• Statistical method
• Reduces noise and sensor errors
• Coordinate Transformation
• Directional Cosine Matrices (DCM)
• Body to Navigation

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The AHRS

• Accelerometers
• Range
• /- 0.5 gs
• Resolution
• 12-bit - 0.2 mg
• Gyroscopes
• Range
• /- 25 /s
• Resolution
• 12-bit - .01 /s
• Full updates at no less than 10 Hz
• Heading, Roll, Pitch, and Yaw, velocity, and
  position

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Future work

• Senior project
• Build and test AHRS
• Couple AHRS with DGPS
• Bound the sensor errors
• Full UAV navigation solution

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Special Thanks

• Dr. Gary Gear Faculty Mentor
• Dr. David Viger and David Brandstein
• - McNair Director and Coordinator
• College of Engineering Faculty
• Embry-Riddle Aeronautical University

McNair Scholars Program