North Carolina State University
Aerial Robotics Club
Autonomous Reconnaissance System
Authors:
Dan Edwards
Matt Hazard
JB Scoggins
Matthew Strautmann
Submitted:
1 June, 2006
Abstract
This paper describes the North Carolina State University Aerial Robotics Club
Autonomous Reconnaissance System designed specifically to meet the 2006 AUVSI’s
Student UAV Competition mission. Without human control, the UAV flies through a
series of GPS waypoints to reach a search area. Once arrived, the vehicle searches for
ground targets, reporting the number, orientation, and location of the objects through a
custom imagery viewer program developed by NCSU ARC members. NCSU’s design
uses mostly off-the-shelf components to create a modular and simple system. The overall
system is broken down into four sub-systems: vehicle, autopilot, aerial imagery, and
ground station. In event of an in-flight failure, backup systems and failsafe modes
attempt to regain control before a hard-over failsafe is used, creating a robust and safe
system.
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Table of Contents
ABSTRACT .................................................................................................................................................. 1
TABLE OF CONTENTS ............................................................................................................................. 2
MISSION REQUIREMENTS ..................................................................................................................... 3
DESIGN OVERVIEW ................................................................................................................................. 3
SYSTEMS ENGINEERING........................................................................................................................ 3
A.
B.
C.
D.
INTERFACE REQUIREMENTS .................................................................................................................. 3
SYSTEMS ENGINEERING ........................................................................................................................ 4
TEST PHILOSOPHY ................................................................................................................................. 5
PROCEDURES......................................................................................................................................... 5
VEHICLE ..................................................................................................................................................... 7
E. TWELVE FOOT TELEMASTER ................................................................................................................. 7
F. PAYLOAD COMPARTMENT ..................................................................................................................... 7
G. WING HARD-POINTS ............................................................................................................................. 7
H. CENTER OF GRAVITY ............................................................................................................................ 7
AUTOPILOT ................................................................................................................................................ 8
I. FLIGHT ALGORITHM ............................................................................................................................... 8
J. FLIGHT PATH REQUIREMENTS ................................................................................................................ 8
K. PERIPHERALS ........................................................................................................................................ 8
L. SERVO CONTROL ................................................................................................................................... 9
M. PAYLOAD CONTROL ............................................................................................................................. 9
AERIAL IMAGERY.................................................................................................................................. 10
N. NIKON D50 AND CAMERA STABILIZATION SYSTEM (D50) ................................................................. 10
O. ONBOARD IMAGERY COMPUTER (“LEVIATHAN”) ............................................................................... 10
P. WIRELESS IMAGE TRANSFER ............................................................................................................... 11
Q. HIGH-RESOLUTION PHOTOGRAPHS ..................................................................................................... 11
R. GROUND STATION IMAGERY ANALYSIS SOFTWARE............................................................................ 12
GROUND STATION ................................................................................................................................. 13
S. MICROPILOT GROUND STATION .......................................................................................................... 14
T. IMAGERY ANALYSIS COMPUTERS........................................................................................................ 14
SAFETY ...................................................................................................................................................... 16
U. NO-FLY ZONES ................................................................................................................................... 16
V. COMMUNICATION LOSS ...................................................................................................................... 16
W. RADIO FREQUENCY INTERFERENCE ................................................................................................... 16
X. POWER/BATTERY SAFETY................................................................................................................... 16
Y. FAILURE ANALYSIS ............................................................................................................................. 17
Z. RC SAFETY SWITCH ............................................................................................................................ 19
CONCLUSION........................................................................................................................................... 20
ACKNOWLEDGEMENTS ....................................................................................................................... 20
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Mission Requirements
The 2006 AUVSI Student UAV competition mission is two-part:
1. Fly autonomously through a series of GPS waypoints
2. Survey a search area for ground-based targets – feeding back target count,
location, and orientation
In addition, new waypoints will be given mid-mission and must be uploaded in flight.
Time to complete the mission is 40 minutes. An emphasis on a user-friendly and robust
system is important. Spectator and operator safety is paramount, requiring the
observation of no-fly zones and flight termination procedures.
Design Overview
A modified, twelve-foot Telemaster airframe carries a 20 lb max payload at 40 mph for
35 minutes flying time assuming a five minute reserve. After a manual takeoff, a
Micropilot 2028g autopilot guides the aircraft through given GPS waypoints and begins a
semi-circular orbit pattern over the search area. A wireless modem connects the ground
station and autopilot for in-flight reprogramming. Once in the air, an orthogonally
stabilized Nikon D50 regularly takes pictures encoded with GPS and heading information
and sends them to a ground server for saving and viewing. The images are then loaded
into a custom imagery program which displays a continually updated mosaic of the
pictures downloaded from the flying aircraft. A ground operator can then search this
mosaic for possible targets, tagging them to get location and heading reference. Once all
targets are found, a target reference sheet is printed for the judges.
Systems Engineering
A. Interface Requirements
Before system design, NCSU examined the team-judge interface requirements. The
judges need to:
• Distribute GPS waypoints and mission boundaries before mission
• Distribute dynamic re-tasking requirements during mission
• Receive an imagery hard-copy for post-flight assessment
To meet these requirements, NCSU created an interface control diagram to govern the
exchanges of information. Judges will hand a list of waypoints or dynamic targets to the
team. The team will return a hard-copy of selected target imagery to include target
location, orientation, and a list of all sited targets. The judges will confirm waypoint
capture by watching the GCS screen or via independent verification.
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Interfaces Block Diagram
B. Systems Engineering
Starting with the interface requirements, NCSU designed a system that can meet the
AUVSI Student UAV Competition mission requirements. The system is broken into four
separate sub-systems:
1. Vehicle
2. Autopilot
3. Aerial Imagery
4. Ground Station
These four sub-systems are further divided into discreet components, maintaining
modularity and utilizing commercial-off-the-shelf (COTS) parts when possible.
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System Block Diagram
C. Test Philosophy
To ensure quality manufacturing and to certify the system, NCSU adopted a thorough
testing policy. First, each sub-system was tested individually to ensure proper operation
with a minimal risk. Then, each sub-system was test-flown individually to ensure proper
airborne operation. Last, the sub-systems were added together one at a time and test
flown. This ensures any failures are easily traceable and do not result in loss of the entire
system. In-flight failure testing of parts is conducted in controlled environments when
possible.
D. Procedures
NCSU created and followed Standard Operating Procedures (SOP) to control vehicle and
autopilot operation, team/judge interactions, and emergency procedures. NCSU also
conducted competition simulations to practice target reporting techniques and document
the methods.
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Example SOP Excerpt
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Vehicle
The competition vehicle requirements are quite simple: integrate and carry a payload with
easy access to the payload compartment. Additionally, the autopilot needs a stable,
conventional aircraft for the controller for easiest integration. Takeoff and landing
distance must be below 250 feet to safely use the 450 foot NCSU test runway. To
accommodate dynamic airspeed requests, the vehicle must have a wide flight speed
envelope. Since NCSU undergraduates will be piloting the aircraft, handling must be
excellent and the aircraft must be Academy of Model Aeronautics (AMA) certified.
E. Twelve Foot Telemaster
To meet the vehicle requirements, Hobby-Lobby Inc. donated a twelve-foot Telemaster
fixed-wing aircraft with large fuselage volume and ample wing area for high lift. NCSU
constructed the balsa and ply aircraft stock from plans with a few major modifications:
• Fully boxed wing spar and carbon fiber cap-strips – for extra structural margin
• Integrated wiring conduit tubes – for easy payload integration
• Lock-pin attached wings instead of bolt-on wings – to facilitate quick attachment
and removal of the wings during setup and breakdown
• Improved strut design – to increase the structural margin of the wings
• Doubling the width of the fuselage – for increased payload volume
A 2-stroke gas engine is mounted in tractor configuration and runs for 35 minutes on a 40
ounce fuel tank at 40 mph cruise speed (approximately half throttle) with a max power of
3.8HP. Ballasted test flights to 45.2 pounds takeoff weight have certified the airframe
and verified all handling requirements are met while fully loaded.
F. Payload Compartment
Since the measure of a good transport vehicle is how well it carries payload, the
Telemaster has been constructed to have an open 21" x 11" x 11" main payload bay and
an 11” x 10” x 15” optional payload space in the tail immediately aft the wing. The main
volume is roughly centered over the Center of Gravity (CG) and can carry up to 20lb of
payload. Vibration sensitive components have been bolted with anti-vibration mounts
and all flight critical necessities such as the fuel tank and batteries are located in a 11” x
10” x 9” front compartment for easy access.
G. Wing Hard-Points
NCSU installed generic mounting hard-points in both wings during construction. This
allows all wing-mounted payloads to interchange between left and right wing and helps
easily correct lateral balance. Currently, the pitot-static probe system is attached at one
of these wing-mount locations.
H. Center of Gravity
The Telemaster CG is 4” behind the wing leading edge, per the plans. The CG is roughadjusted by initial payload location weight & balance estimations. Fine tuning the
balance for various payloads is accomplished by shifting the batteries fore or aft in the
fuel tank compartment. Lateral balance is fine-tuned by adding/removing lead shot to a
small wing-tip hatch.
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Autopilot
The AUVSI mission requires a few specific capabilities from an autopilot:
1. Navigate via GPS waypoints
2. Receive new waypoints in-flight
3. Receive new flight parameters (speed, altitude) in-flight
NCSU chose the Micropilot 2028g Autopilot because of our familiarity with the system
and because it has the required capabilities built-in, once a wireless modem is attached.
NCSU housed the Micropilot in a compact and lightweight aluminum enclosure.
I. Flight Algorithm
To fly the aircraft, the Micropilot uses 9 PID loops with feedback from an onboard 3 axis
gyro and accelerometer. A GPS receiver updates the aircraft location with 1ft accuracy at
1Hz. Airspeed and altitude pressure transducers supplement the GPS data.
To set up the Micropilot with an airframe, a series of test flights are needed to tune the
PID loops. The included PID gains will roughly fly a 60” wingspan trainer. NCSU
conducted the necessary series of tuning flights and found the stock gains to be
acceptable even for the larger vehicle. This short tuning process was aided by a smart
choice of a stable and conventional aircraft.
For each autonomous flight, a “fly-file” is created that specifies the desired flight
behaviors. Commands such as FlyTo (lat, lon) describe how the aircraft should fly
through waypoints. Both path-based and heading-based controls are used together
complete the flight objectives. This file can be modified in-flight to adjust for new
missions or changing environments.
J. Flight Path Requirements
The vehicle must fly directly over top of targets in order to capture them with the imagery
system. However, the vehicle can have pitch or roll components, easing workload on the
autopilot operator since the attitude can be out of level. Since flying over a target is
equivalent to flying over a waypoint, the flight path requirement from imagery is easily
accomplished similar to adding a new GPS waypoint. Also, the imagery system has a
wide field of view for capturing targets not directly beneath the aircraft.
K. Peripherals
The Micropilot requires a few sensors to be integrated in the airframe, outside of the main
compartment.
• The GPS antenna is mounted near the tail to reduce RFI from the payloads.
• A pitot-static probe is mounted 40 inches out the left wing to avoid the slipstream
of the propeller; the pressure tubing runs through the wing into the main payload
compartment.
• A Microhard 900MHz serial modem is mounted in the payload compartment next
to the Micropilot. It is housed in an aluminum enclosure for reduced RF
emissions and easier handling. It constitutes the low-bandwidth (57600 baud),
high reliability command and control link to the plane.
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Micropilot System Diagram
L. Servo Control
NCSU implements servo control differently than suggested by Micropilot. The autopilot
servo outputs are sent to an RC Safety switch and then sent to the servos. The NCSU
switch can change to manual control mode even with loss of autopilot power. This
separates the autopilot from the critical path of manual servo control. This also allows
ability to change autopilots without affecting the aircraft’s critical flight systems.
Safety Switch Diagram
M. Payload Control
The Micropilot partially supplements the imagery payload. Micropilot stabilizes the D50
camera mount to point straight down through the use of a simple table lookup function.
This stabilization occurs at approximately 30 Hz, fast enough to eliminate problems from
induced camera shake.
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Aerial Imagery
The Aerial Imagery payload is the most important sub-system. The imagery system
operators must be able to locate and identify targets while ensuring complete coverage of
the target area and balancing key factors like field of view and target resolution, both of
which are affected by altitude and zoom level. Judges also need high quality imagery and
accurate target data in near real-time to assess and evaluate the ground targets. Judges
need very concise and detailed target information.
To fulfill these requirements, NCSU has opted for a digital imaging system that consists
of the following components:
• Nikon D50: A high-resolution camera that can be controlled remotely and
interfaces with onboard computers for the retrieval of picture data
• An onboard computer that interfaces with the camera, position sensors, and the
802.11g 2.4 GHz data link to the ground station computers.
• Imagery analysis software that enables the quick processing of collected imagery
and generates a report suitable for printing or display.
• A printer that creates hard copies of high-resolution target imagery and position
information for post-flight analysis.
This system relies on the successful interaction between ground station computers and the
onboard systems. But, each component is configured to permit imagery collection and
analysis to be performed regardless of the status of the data link.
N. Nikon D50 and Camera Stabilization System (D50)
The primary imagery sensor is a Nikon D50, an off-the-shelf digital SLR. The sixmegapixel camera is mounted on a servo controlled two-axis mount in the camera bay of
the fuselage. The autopilot runs a stabilization function that reads from the autopilot
gyros and moves two servos to cancel out aircraft pitch and roll. This code (implemented
in the form of a table lookup function) runs at 30Hz to provide smooth and accurate
motion stabilization. The camera is also fitted with a servo-controlled zoom lens to
ensure the optimal field of view at the desired flight altitude.
O. Onboard Imagery Computer (“Leviathan”)
The onboard camera controller and wireless link is built on a 3.5” embedded mini-board
computer, nicknamed "Leviathan." It has a 666MHz processor and boasts standard
desktop computer features (USB, Ethernet, sound card, serial ports, video, etc). The
device has been extended with the built-in PC/104+ expansion slot to include an 802.11g
wireless data transmitter capable of 400mw transmit power. The D50 is operated over the
built-in USB 2.0 interface. Custom software enables the camera to capture photos and
send them to the computer without ever saving them to a flash memory card.
The onboard software then inserts position and orientation data into the EXIF header of
each image. This data is parsed by conventional photo editing software or NCSU’s
custom imagery viewer. The position and orientation data is derived from external
sensors: a single GPS receiver determines position and approximate heading and altitude,
while additional sensors, such as a magnetometer or altimeter, can be added to improve
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the precision of these measurements. Each photo is saved on the 4GB miniature hard
drive, which has room for approximately 1,350 photos.
Leviathan
P. Wireless Image Transfer
The images stored on the onboard computer must be transmitted to the ground station
before they can be analyzed. Operators can choose to download pictures once the vehicle
has landed (by connecting to the computer with a standard Ethernet cord) or attempt to
transmit them over the 802.11g data link while in flight. Initial tests showed that this
wireless link was prone to interference and intermittent failures. This problem has been
moderated by sending the photos with a custom server that configures the connection for
the unreliable link. An incomplete picture transfer is resumed once the link is regained.
This wireless link is further enhanced by the use of high-power (400mw) transmitters, an
8.5dbi omni-directional antenna on the plane, and a 23dbi parabolic grid antenna on the
ground.
Q. High-Resolution Photographs
Each photo captured by the D50 is a 3008x2000 (6 megapixel) image. The ground
coverage depends on the altitude and zoom level, but at full zoom out the camera is
capable of a 65° viewing angle. At 500 feet of altitude this constitutes a field of view of
over 630 feet, and at 1000 feet above ground each picture will cover up to 1200 feet. The
Nikon lens has very little distortion through most of the zoom range, but at extreme wide
angles the radial distortion is noticeable, making straight lines appear slightly curved.
This effect is compensated for in the imagery viewer.
Testing has revealed that photos from above 1000 feet can be valuable for locating points
of interest, but the resolution of actual targets is too low to be useful. For the most part,
imagery collection will occur at or under 500 feet, exceeding this altitude only to perhaps
get an overview of the entire target area in one photo.
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Orthophoto from 2000 Feet AGL. The Runway is 450 Feet Long.
R. Ground Station Imagery Analysis Software
The imagery viewer/analysis software is a tool to help speed up the processing of
collected imagery. A central server accumulates all the collected photos. It parses the
orientation information and decompresses the JPEG images as they are retrieved (while
the plane is flying, if transmitting wirelessly). Each connected viewer (the system
supports multiple analysts) displays a bird's-eye-view of the entire area. Incoming
pictures are placed according to their recorded position and orientation, effectively
mosaicing them in real time. Each picture is corrected for lens distortion as well.
The user interface provides simple point mechanisms to mark a target's location, heading,
and size. The analyst can zoom, pan, and rotate the scene. He can generate an HTML file
suitable for printing that contains close-ups of each target. In addition, he can select
waypoints (to re-task the autopilot) to areas of interest or correct for gaps in coverage. By
displaying all the images in their true geo-referenced position, the system is spatially
coherent and user friendly, leading to an increase in operator efficiency, accuracy and
speed.
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Ground Station
Once the telemetry and video are sent to the ground station, the information still needs to
be displayed in a user-friendly setup. NCSU opted to place the ground station in a 6 by
12 foot trailer with three computer stations. Two operators can simultaneously search for
targets on the imagery software while the third operates the Micropilot software. For the
operators, the Micropilot station has a laptop, and the imagery software has two desktops
running LINUX.
Ground Station Layout
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S. Micropilot Ground Station
Micropilot HORIZON Ground Control Station (GCS) requires a standard PC for
command and telemetry, so a laptop with integrated monitor performs this task. For
operator feedback and control, NCSU has fitted a wireless modem to the Micropilot
2028g and GCS for real-time flight telemetry at a 5Hz update rate. A stationary 5.5 dbi
omni antenna is sufficient to ensure long range operation of the 900 MHz telemetry link.
Telemetry Fields
The Horizon GCS gives vehicle airspeed, altitude, heading, and GPS location overlaid on
a satellite image of Webster field. For dynamic re-tasking, the operator clicks the floating
map to place a new waypoint or clicks a scrollbar to change flight parameters.
T. Imagery Analysis Computers
The imagery analysis portion of the ground station consists of several desktop computers,
running Debian GNU/Linux and custom software. One acts as the wireless base station
for the remote vehicle and ground station server. It retrieves photos from the vehicle's
onboard computer, and prepares them for viewing on one or more ‘client’ or ‘viewer’
computers. All of the imagery computers are networked with a 1000 Mbit/s link, enabling
quick transfer of decompressed images between the server and clients. Each viewer
station displays the entire set of collected imagery and is free to operate independently of
the others. The system enables multiple analysts to work in parallel, increasing the
likelihood that all targets will be identified correctly.
A unique feature of the ground station software is the ability to load hundreds of images
into the viewer, while even the newest COTS graphics cards can only hold a couple
dozen high-resolution images in accelerated memory. The NCSU system selectively
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pages images in and out of texture memory to optimize for a given hardware
configuration, using a priority system based on where the user viewing area, zoom level,
and so on. Another key feature is real-time lens distortion correction, a pixel-by-pixel
operation that is done entirely on the graphics card, leaving the CPU free for other
computationally expensive operations.
Screenshot of the Imagery Viewer, Showing 6 Selected Targets
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Safety
Both spectator and operator safety is of paramount importance. In addition to a failure
mode event analysis (FMEA), specific component and system choices ensure a controlled
and safe operation at all times.
U. No-Fly Zones
AUVSI will designate "No-Fly Zones" on the day prior to the competition flight. For
quick visual reference, the no-fly zone boundaries will be outlined in red over the
Webster Field GCS image. Horizon GCS is programmed with no-fly boundaries, and will
automatically divert from headings which would require exit from the competition area.
To back up this built-in functionality, computer simulations will ensure no boundary
violations are planned. The GCS operator will monitor the flight path closely to ensure
dynamic waypoints will not result in boundary violations. The operator can also drag
waypoints around and quickly change the aircraft’s heading if needed.
V. Communication Loss
AUVSI rules state that a manual control system must be in place in case of autopilot
failure. Furthermore, in the event of manual system control loss, the vehicle should
execute a hard-over. To meet this requirement, NCSU uses a PCM RC receiver with a
programmed "fail-safe" that defaults the RC Safety Switch to manual and executes a
right-handed hard-over.
W. Radio Frequency Interference
RFI is extremely important since the loss of RC communication triggers a hard-over,
potentially destroying the aircraft. Over previous years, NCSU has faced numerous radio
hits and other interferences at competition and has therefore worked to increase the RC
receiver signal-to-noise ratio. To limit RF emissions from onboard components, all
computer boards are mounted in grounded metal enclosures, reducing incoming and
outgoing RF noise. Antennas have been located as far as possible away from each other
and with short cables to reduce stray RF emissions and overlapping signals. Flight testing
has confirmed a reduction in RFI related problems.
X. Power/Battery Safety
During all ground operations, an external power supply powers the aircraft. This reduces
operator workload checking and charging onboard batteries constantly. The external
power source can be switched on or off without shutting down the complete system for
easy transition to a flight-ready mode.
During flight, battery voltages are monitored via the Horizon GCS telemetry link. A low
voltage case throws a red flag and appropriate action per the FMEA can be taken. The 6v
NiMh is the only flight critical battery; however, all batteries will be topped off prior to
competition flight to ensure proper systems operation. Battery capacity has been chosen
to give a 60 minute or more duration.
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Power Diagram
Y. Failure Analysis
To understand the consequences of component failures, NCSU conducted an intense
FMEA. Recoverable failures are best, where backup systems take over or compensate for
the failure. Mission-critical failures are recoverable, but result in loss of a system needed
to complete the mission. Catastrophic failures result in loss of the aircraft.
The FMEA shows the NCSU system is single-fault tolerant, with the exception of the RC
receiver, its battery, and the safety switch hardware. A loss of any other component is
tolerable, showing the NCSU system is extremely robust and safe.
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Failure Mode Event Analysis
Failure Mode Event Analysis
Failure
Symptom
RC Receiver
malfunction
erratic
behavior
Action
1. pilot defaults to manual control
2. if problem persists, pilot turns off transmitter,
initiating hard-over
1. switch to manual mode
erratic
Vehicle breaks
behavior,
in-flight
2. pilot attempts to fly damaged aircraft
falling debris
3. turn off transmitter to activate hard-over
1. autopilot attempts to fly without servo
2. if flight appears erratic, switch to manual control
One servo dies
erratic
behavior
3. pilot attemps to fly aircraft, lands
4. if condition irrecoverable, activate kill
mechanism
change in
1. pilot switches to manual mode
Engine dies in aircraft sound,
noticable drop
flight
2. emergency landing procedure
in airspeed
Status
mission failure,
recoverable
catastrophic
mission failure,
recoverable
mission failure,
recoverable
catastrophic
mission continues
mission failure,
recoverable
mission failure,
recoverable
catastrophic
mission failure,
recoverable
mission failure,
recoverable
6v servo
battery low
indicated on
1. pilot switches to manual and lands immediately
GCS screen
mission failure,
recoverable
12v payload
battery dies
indicated on
1. pilot defaults to manual control
GCS screen
mission failure,
recoverable
Autopilot
malfuction
Loss of GPS
signal
Autopilot
uplink lost
Imagery uplink
lost
Loss of sight
of vehicle
erratic
behavior
1. pilot defaults to manual control
1. aircraft initiates a 30 degree bank orbit
GPS link
maintaining pressure altitude
indicator red 2. If GPS signal does not return after one minute,
switch to manual
mission failure,
recoverable
mission continues
mission failure,
recoverable
telemetry data 1. cannot provide dynamic control; watch closely for
mission continues
stops
link to return
picture
download
intermittant
1. wait to see if link returns
2. GCS operator commands fly-by
3. download images after landing
1. pilot orders camera operator to point forward
pilot calls "out
2. pilot flies via the video TV screen
of visual
3. backup pilot watches sky for vehicle
range"
4. pilot resumes watching vehicle in the sky
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mission continues
mission continues
Z. RC Safety Switch
As a direct result of an early FMEA, an external RC Safety Switch was added between
the manual RC receiver, autopilot, and servos to govern servo control. The safety switch
is common power to the manual RC receiver, thus always giving ability to manually
override the autopilot. This separation of the servo switching from the autopilot allows
the autopilot to fail without affecting manual control.
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Conclusion
The NCSU system can complete the AUVSI mission fully and within the given time limit
while following all rules and regulations. Splitting into four sub-systems helps NCSU
divide and conquer, allowing modularity, use of COTS parts, and make easy future
modification of individual sub-systems. The judges’ target imagery hard-copy printer
gives concise target evaluation in near real-time and more detailed high-resolution
images upon request. Dynamic re-tasking is accomplished through a wireless link
between the Micropilot and the ground station. The imagery viewing software sets us
apart from other known UAV systems. NCSU believes it gives unparalleled speed to
acquire, identify, and track targets while strengthening situational awareness.
Additionally, the ground station trailer setup makes our information easily accessible to
an audience and keeps team members focused. This level of operation encourages
professionalism and maintains focus on a common goal. North Carolina State University
is prepared to fully complete the 2006 AUVSI Student UAV Competition mission.
Acknowledgements
North Carolina State University's Aerial Robotics Club is proud and honored to compete
in the 2006 AUVSI Student Unmanned Aerial Vehicle Competition and would like to
thank the following sponsors, who made our participation possible:
•
•
•
•
•
•
•
•
•
•
•
•
•
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AeroCraft RC
Analog Devices
Gumstix
Jay Francis
Leica Geosystems
Malcolm McAllister
Microhard Systems, Inc.
NCSU Engineer’s Council
NCSU Flight Research
NCSU Student Government Association
NCSU Mechanical and Aerospace Engineering Department
PNI
ReadyToFlyFun.com
US Global Sat, Inc
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