MODEFLIER
Mode-Demonstrating Flying Laboratory:
Instruction and Experiment in Real-time
Test Readiness Review
University of Colorado Boulder
March 4th, 2015
Riccardo Balin
Christian Ortiz-Torres Jeffrey Snively
Quinn Kostelecky
Matthew Slavik
David Thomas
Jas Min Ng
Tyler Smith
Hindrik Wolda
Problem Statement and
Critical Project Elements
Develop a small, low-cost aircraft system to demonstrate
the phugoid, Dutch roll, and spiral modes for future ASEN
3128 students.
CPE1: Phugoid, Dutch roll, and spiral mode demonstration
– Overarching purpose of project
– Unusual task, as aircraft and control systems are typically designed to damp
modes
CPE2: Control system
– Means by which mode demonstrations are accomplished
– Requires the most time and effort
CPE3: Ground station communication
– Must reliably handle commanding of aircraft, RC manual override,
and telemetry downlink
CPE4: FAA Approval
– COA Obtained February 12
– Airframe: Techpod
– Flight location: Boulder South Campus
Overview
3/4/2015
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
2
Concept of Operations
Pilot Controlled
Pilot Controlled
Overview
3/4/2015
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
3
Functional Block Diagram
Aircraft
Aircraft
Battery
Battery
Throttle/servo settings and RC override PWM
Video Camera
Autopilot
Autopilot
Transceiver
Transceiver
Light
Multiplexer switch
control (RC
override PWM)
LED
Current
LED Driver
Manual PWM
throttle/servos
Either
Eithermode
modedemonstration
demonstration
waypoint
PWMCurrent
PWM
commands
commands
or waypoint
Aircraft
Aircraftstate
state variables
variables
Eithermode
mode
Either
demonstration
PWM
demonstration
Current
Waypoint
PWM
commands
or
commands
waypoint
Turn on LED
PWM
Multiplexer
Multiplexer
Manual throttle/servo settings and RC override (on/off) PWM
RC Receiver
Mode
Mode demo
demo Current
Currentwaypoint
waypoint
PWM
PWM
No
No
Demo?
Demo?
A/C
state
variables
Measured
Measured
Aircraft
AircraftState
State
Sensor
Sensor Package
Package
Physical
Physical
Aircraft
Aircraft State
State
(e.g.
(e.g. altimeter,
altimeter, rate
rate gyro)
gyro)
Physical
Physical
dynamics
dynamics
PWM
PWMthrottle
throttle setting
setting
Current
Electronic
Electronic Speed
Speed Current
Controller
Controller
PWM
PWMservos
servos setting
setting
Servos
Servos
Plots of
A/C state
variables
AUTOPILOT
AUTOPILOT
Aircraft
AircraftState
State
Control
Controlsurface
surface
deflections
deflections
Motor
Motor
Torque
Torque
Propeller
Propeller
Control
Control Surfaces
Surfaces
Thrust
Thrust
Change
Changein
in
aero.
aero.forces
forces
3/4/2015
Visual
Display
Propulsive
Propulsive
Forces
Forces
Audience
Aerodynamic
Aerodynamic
Forces
Forces
GS
GS Operator
Operator
Demo?
Demo?
Desired RC
override setting
(on/off)
University of Colorado Boulder
Aerospace Engineering Sciences
Mode
Mode Excitation
Excitation
Functions
Functions
GS
GS COMPUTER
COMPUTER PWM
throttle/servo
RC Control
settings
Sticks
Override
PWM (on/off)
Control Switch
RC CONTROLLER
GROUND
GROUND STATION
STATION
Blocks
Blocks
Arrows
Arrows
Bought
Radio
Radio signal
signal Bought
PEOPLE
PEOPLE
Ground Testing
Mode
Mode command
command
Hand-operated
control
Pilot
Pilot Controlled RC
Autonomous Waypoint Tracking
Mode Demonstrations
Schedule
Steady
Steady
flight
flight or
or
mode
mode
command
command
Plots of A/C state
variables
View of aircraft
position, attitude,
and speed
AIRCRAFT
AIRCRAFT
Overview
No
No
Yes
Yes
Mode
Mode demo
demo
A/C
A/C
PWM
PWM
state
state
commands
variables
variables commands
Steady
Steady
flight
flight
command
command
Mode
Mode
Data
Processor
Aircraft
Aircraft
state
state
variables
variables
Aircraftstate
state
Autopilot
AutopilotAircraft
variables
variables
Waypoint
Waypoint
Digital
Digital Data
Data Storage
Storage
Processor
Processor
PWM
PWM
PWM
PWMthrottle/
throttle/
servo
servosettings
settings
Current
Currentwaypoint
waypoint
A/C
A/Cstate
statevariables
variables
Mission
Mission Planner
Planner Flight
Flight Control
Control
Mode
Mode
Yes
Yes
Ground
Ground Station
Station Either
Eithermode
mode
demonstration
demonstration
waypoint
PWM
PWMcommands
commands
or waypoint
Transceiver
Transceiver Current
Ground
Ground
Station
Station Power
Power
Flight Testing
Electrical
Electrical
Modified
Modified
Visual
Visual
Designed
Designed
Physical
Physical
External
External
Power
Power
Power
Power
conditioned
conditioned
from
from source
source
Internal
Internal
power
power
source
source
KEY
KEY
Budget & Summary
4
Levels of Success
• Level 1
– Record flight data
– 2/3 modes demonstrated
• Level 2
– Live data downlink and
display
– All 3 modes demonstrated
– Record flight video
– Autonomous mode
demonstrations
commanded by Ground
Station
– 10 students can view
ground station
– Perform demonstrations in
110 minutes (1 lab period)
• Level 3
– Fit aircraft and ground
station in SUV cargo bay
Overview
3/4/2015
Schedule
– Reproducibility
• Aircraft: $1,000
• Ground Station: $2,000
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Indicates
Completed
Budget & Summary
5
Schedule
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
6
Test Breakdown Structure
Avionics
GPS
Resolution
Communications
Aerodynamics
Surface
Deflection
Structures
Range Test
Airspeed
Sensor
Ground
Station
Latency
Analysis
Camera Life
Data Display
Propulsion
RC Override
LED Sync
GS Power
Life
A/C Battery
Life
SUV Space
Test
CG Test
Tip Test
Software
Ground Dry
Run
SITL
Waypoint
RC Flight
Test
SITL Mode
Excitation
Auto. Steady
Flight Test
Flight Testing
Ground Testing
Overview
3/4/2015
Systems
Mode Demo.
Flight Test
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
69% of tests completed,
44% of estimated test time completed
Incomplete
Flight Testing
Started by
TRR
Completed
by TRR
Budget & Summary
7
TRR
2/22
2/15
3/22
3/15
3/8
3/1
GPS Test
Data Display
Test Plan
3/29
Spring Break
Subsystem Testing
Progress
Status: 97% Complete
Time Spent: ~19 hours pp.
Time Remaining: ~6 hours total
Latency Analysis
Battery Life Test
Airspeed Sensor
Range Test
RC Override Test
Ground Station Power
Camera Life Test
Aircraft Integrated w/ Avionics 2/26
Aircraft Assembled 2/19
CG Test
4/5
Contingency
Ground Testing
Status: 50% Complete
Time Spent: ~18 hours pp.
Time Remaining: ~18 hours pp.
Time Available: ~28 hours pp.
Flight Testing
First Flight: ~March 9th
Time Spent: N/A
Time Remaining: ~27 hours pp.
Time Available: ~49 hours pp.
Ground Dry Run
Tip Test
Control Surface Deflection
Autonomous Steady Flight (Waypoint Following)
RC Flight Test
Mode Demonstrations
SITL Required for Autonomous Steady Flight
SITL Required for Mode Demonstrations
SUV Space Test
Overview
3/4/2015
LED Sync Test
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
8
Ground Testing
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
9
Aircraft Simulink Model
Latency
Dynamics
Aerodynamics,
Thrust, and Gravity
Equations
Integration of
Aircraft Equations
of Motion
Using Aircraft Parameters
(Etkin[1])
Servos
Wind Gust
Mode
Excitation
Wind
(MATLAB gust
model[2] and
NOAA wind data
for Boulder[3])
Control Law
Sensors
Overview
3/4/2015
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
10
Aircraft Simulink Model
Latency
Dynamics
Aerodynamics,
Thrust, and Gravity
Equations
Integration of
Aircraft Equations
of Motion
Using Aircraft Parameters
Servos
Elevator
Deflection
Wind Gust
Mode
Excitation
Remove
Longitudinal
Control
(Etkin[1])
Wind
(MATLAB gust
model[2] and
NOAA wind data
for Boulder[3])
Control Law
Sensors
Overview
3/4/2015
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
11
Software in the Loop
Latency
Aerodynamics,
JSBSim Aircraft Dynamic Simulator
Integration of
Thrust,
and Gravity
[5])
(Equations
of Stevens and Lewis[4] Aircraft
and of Zipfel
Equations
Equations
of Motion
Using Aircraft Parameters
Dynamics
(Etkin[1])
Servos
Wind Gust
Mode
Excitation
Control Law
in Python
functions
Overview
3/4/2015
Wind
(MATLAB gust
model[2] and
NOAA wind data
for Boulder[3])
Sensors
Not modeled
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
12
Software in the Loop
Purpose:
• Implementation of mode demonstration functions in Python
• Verification of mode demonstration control law on alternate simulator
SITL Spiral Response for Default Aircraft
Completed:
• Aircraft state data recorded
180° design
End of mode
throughout simulation
requirement
demonstration • Successfully ran mode
demonstration function
Nominal
• Aircraft successfully follows
exponential
waypoints
spiral
response
SITL data
Remaining:
• Modifying aircraft parameters
Start of mode
demonstration
in simulator to match Techpod
Overview
3/4/2015
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
13
Latency Characterization
1. Data Measurement (Autopilot
State Estimation) (1-2 ms)
Total Latency
111 ms
Tolerance
200 ms
Safety Factor
1.8
2. Aircraft to Ground Station
4. Ground Station to Aircraft
Communication (9-41 ms)
Communication (5-33 ms)
3. Feedback Processing
(Python Functions) (20-35 ms)
Example Damping of Unwanted Dutch Roll
Latency above
Tolerance: 300 ms
Total Expected
Latency: 111 ms
No Latency
Overview
3/4/2015
Schedule
Latency at
Tolerance: 200 ms
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
14
Ground Dry Run
Purpose: Verifies design requirements and reduces time that a pilot is needed
•
•
Range Test
Performed at
Communication
flight location:
Lost Link Protocol
for full COA area
South Campus
Record State Variables
No power to
motor – •willVerifies aircraft follows pre-programmed flight maneuvers if DR2.1: Aircraft
state measured
walk aircraftcommunication is lost (design)
RC Override
Verifies 7 design requirements
Video/LED•Sync
DR3.3: Pilot can
• •Adds
confidence
that
aircraft
fly towards
audience (safety)
Camera
Linewill not
Completes
flight-test-related
objectives
without
DR4.2: Video
take full control
of Sight
• Reduces
likelihood of
aircraft crashing and suffering significant
paired with
data
presence of pilot
Data Transmission
damage
(risk mitigation)Test Area
Data Display
DR2.2 & 2.3: Real-
• Builds confidence in safety
• Familiarizes team with flight test procedures
DR2.2 & 2.3: Realtime data at 10Hz
time data at 10Hz
Battery Swap Time
Ground Station Endurance
DR1.5: Electronics
run for 110 mins
DR1.5: All demos
in 110 mins
Lost Link Protocol
Aircraft path is
predictable
Servo Check-Out
Proper avionics
connections
Overview
3/4/2015
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
15
Flight Testing
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
16
Aircraft Simulink Model
Latency
Aerodynamics,
Thrust, and Gravity
Equations
Using Aircraft Parameters
Servos
Dynamics
Integration of
Aircraft Equations
of Motion
(Etkin[1])
Physical aircraft
system and
Wind
environment
Wind Gust
Mode
Excitation
Control Law
in Python
functions
Overview
3/4/2015
(MATLAB gust
model[2] and
NOAA wind data
for Boulder[3])
Sensors
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
17
Flight Testing
RC Flight
3/9 – 3/17
Needed for all test flights:
• Pilot
– James Mack (Primary)
– Doug Weibel (Alternate)
• Observer
Autonomous Flight
3/18 – 3/31
Mode Demonstration
Flight
4/1 – 4/10
– Quinn Kostelecky
• Acceptable weather conditions
– Winds less than 11 m/s
– No precipitation
– Visibility greater than 2 miles
• Location availability
– CU South Campus
FR1: Mode
Demonstrations
Overview
3/4/2015
Schedule
FR3: Autonomous
Flight
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
FR5: Takeoff and
Landing
Budget & Summary
18
RC Flight
RC Flight
3/9 – 3/17
Autonomous Flight
3/18 – 3/31
Improve:
• Safety and Confidence
– FR5: Aircraft can take
off and land safely
– Characterize battery
life
• Visibility
Mode Demonstration
Flight
4/1 – 4/10
Overview
3/4/2015
Schedule
– Perform qualitative
visibility analysis
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
19
Autonomous Flight
RC Flight
3/9 – 3/17
Autonomous Flight
3/18 – 3/31
Mode Demonstration
Flight
4/1 – 4/10
Overview
3/4/2015
Schedule
• FR3: Aircraft can fly
autonomously
– Pixhawk capable of
controlling aircraft
• DR 3.1: Aircraft follows
defined waypoint flight
path
– Characterize flight path
deviation from waypoints
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
20
Autonomous Flight Plan
South Campus
Location
Altitude = 15 m
Max Distance from GS = 220 m
Waypoint R ≤ 10 m
250 m autonomous flight limit
based on RC pilot safety range
228 m visibility
requirement
90 m
320 m
Waypoint
50 m
Ground Station and RC Pilot
Overview
3/4/2015
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
21
Mode Demonstration Flight
RC Flight
3/9 – 3/17
• FR1: Perform each mode
demonstration
• Measure aircraft state data
– Phugoid:
Autonomous Flight
3/18 – 3/31
Mode Demonstration
Flight
4/1 – 4/10
Overview
3/4/2015
Schedule
• Pitch angle
• DR1.2: 2 periods > 5°
amplitude
– DR:
• Yaw angle
• DR1.3: 1 period > 5°
amplitude
– Spiral:
• Yaw angle
• DR1.4: > 180° rotation
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
22
Phugoid and Dutch Roll
Modes Demonstration
Enter steady
level flight
Excite and
demonstrate
natural mode
behavior
Return to Waypoint
Flight Plan
210 m
Estimated
deviation during
demonstration
Mode
Distance Travelled
Duration
Excitation Method
Phugoid
210 m
18 s
3.5ᵒ elevator step for 1 s
Dutch roll
90 m
6s
25ᵒ rudder oscillation for 2.8 s
Overview
3/4/2015
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
23
Spiral Mode Demonstration
Recover steady level
flight and return to
waypoint
Excite and
demonstrate
natural behavior
Enter steady
level flight
Overview
3/4/2015
Mode
Duration
Excitation Method
Spiral
24 s
5ᵒ rudder step for 1 s
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
24
Phugoid Mode Validation
Start of Mode Demonstration
2 Peaks
Above 5°
End of Mode Demonstration
5° Minimum
Pitch
Amplitude
Expected data from
Phugoid mode
demonstration
Overview
3/4/2015
Schedule
FR1 Validated: Aircraft is capable of
demonstrating flight modes.
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
25
Budget & Summary
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
26
Budget
$940 spent on
aircraft
DR1.6: aircraft reproducible for less than $1,000
DR2.4: ground station reproducible for less than $2,000
Under total course budget
$60 aircraft margin
Spending estimate
increased $48 since MSR
$1,000 Aircraft Reproducibility
$1,266 spent on
ground station
$734 ground
station
margin
$2,000 Ground Station Reproducibility
•
•
•
$450 remaining expenditures
-report printing
-symposium poster
-flight test equipment
$3,280 spent to date
$940 spent on aircraft
$1,266 spent on ground station
$1,074 spent on testing, manufacturing, printing, etc.
$1,270 total margin
$5,000 Total Budget
Overview
3/4/2015
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget &
Summary
27
Summary
Level of Success 1
Level of Success 2
Level of Success 3
Requirement
Validated
by:
Requirement
Validated by:
Requirement
Validated
by:
Record flight
data
Sensor Test
10 students can
view ground station
Data Display Test
Aircraft and ground
station fit in SUV
SUV Cargo
Test
Reproducibility
- Aircraft: $1,000
- Ground Station:
$2,000
Finances
2 of 3 modes
demonstrated
Flight Test
Live data downlink
and display
Data Display Test
Autonomous
commands from
ground station
Flight Test
Record flight video
Video/LED Sync
Test
All demonstrations
within 110 minutes
Endurance Test,
Battery change-out,
Flight Tests
All 3 modes
demonstrated
Flight Tests
Overview
3/4/2015
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Indicates
Achieved
Flight Testing
Budget &
Summary
28
Questions?
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
29
References
[1] Etkin, B., and Reid, L. D., Dynamics of Flight: Stability and Control, 3rd ed., John Wiley
& Sons, Inc., Hoboken, NJ, 1996.
[2] “Discrete Wind Gust Model,” MathWorks, URL: http://www.mathworks.com/help/
aeroblks/discretewindgustmodel.html [cited 2 Mar. 2015].
[3] “Boulder Wind Info,” Earth Science Research Laboratory, URL:
http://www.esrl.noaa.gov/psd/boulder/wind.html [cited 2 Mar. 2015].
[4] Stevens, B. L., and Lewis, F. L., Aircraft Control and Simulation, 2nd ed., John Wiley &
Sons, Inc., Hoboken, NJ, 2003.
[5] Zipfel, P., Modeling and Simulation of Aerospace Vehicle Dynamics, 2nd ed., American
Institute of Aeronautics and Astronautics, Inc., Reston, VA, 2007.
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
30
Backup Slides: Dynamic
Modes Natural Response
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
31
Phugoid Mode Response
End of mode
excitation
End of mode
excitation
5° amplitude
requirement
5° amplitude
requirement
Control re-established
Control re-established
DR1.2 Validated: Aircraft is capable
of demonstrating phugoid mode.
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
32
Dutch Roll Mode Response
End of mode
excitation
5° amplitude
requirement
5° amplitude
requirement
Control re-established
DR1.3 Validated: Aircraft is capable
of demonstrating Dutch roll mode.
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
33
Spiral Mode Response
End of mode
excitation
Control re-established
180° amplitude
requirement
DR1.4 Validated: Aircraft is capable
of demonstrating spiral modes
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
34
Backup Slides: Individual
Test Plans
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
35
Radio
Communication
Circuit Block Diagram
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
36
Video/LED Sync Test
Video
Camera
Battery
5V
4A
Pixhawk
Verifies DR 4.1, 4.2 & Level of Success 2:
Video recorded onboard and matched with
mode demonstrations post-flight
(LED setup uses 0.01% of battery life)
Overview
3/4/2015
Schedule
5V
5V
LED
LED
Switch
0.025A
0.02A
Field of View
Test Procedure
① LED lights up given PWM input: begin
mode excitation
② LED blinks at 1Hz: mode demonstration
in-progress
③ LED turns off: end of mode demonstration
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget & Summary
37
Airspeed Sensor Resolution
𝜎𝑊𝑇
Ideal 1:1
• Airspeed corrected for altitude:
– 𝑉𝑎𝑙𝑡 = 𝑉𝑆𝐿
𝜌𝑆𝐿
𝜌𝑎𝑙𝑡
𝜎𝐴𝑆
≈ 1.14𝑉𝑆𝐿
• Airspeed corrected for
altitude:
𝑉𝑎𝑙𝑡 = 𝑉𝑆𝐿
𝑅<
2
2
𝜎𝑊𝑇
+ 𝜎𝐴𝑆
= 0.2 𝑚/𝑠
Linear Fit
𝑉𝐴𝑆 = 0.91𝑉𝑊𝑇 − 0.33
𝑟 2 = 0.99
3/4/2015
≈ 1.14𝑉𝑆𝐿
• Resolution:
• Resolution:
– 𝑅<
𝜌𝑆𝐿
𝜌𝑎𝑙𝑡
University of Colorado Boulder
Aerospace Engineering Sciences
2
2
𝜎𝑊𝑇
+ 𝜎𝐴𝑆
= 0.2 𝑚/𝑠
DR2.1 met: Velocity shall be
measured with a resolution
less than 1 m/s.
38
Battery Life Characterization
3/4/2015
PWM (μs)
Capacity Discharge
rate (A-hr/min)
Approximate Battery
Life (min)
1220
0.0276
110
1324
0.0960
32
1357
0.1261
24.5
1418
0.1900
16
1500
0.3101
9.5
1569
0.4629
6.5
University of Colorado Boulder
Aerospace Engineering Sciences
39
PWM Throttle Input vs. Discharge Rate
• Batteries discharge
more quickly at
higher throttle
(higher speeds)
• This model allows us
to predict battery
endurance based on
required throttle
input
– Cannot accurately
correlate throttle
input to flight speed
until speed data is
collected in-flight
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
40
Battery Duration
• End-of-life defined as
approximately 3.1Ahr
discharged
– LiPo manufactures
recommend never to
discharge more than
80% of total capacity
to preserve battery
longevity
• RC flight test data will
correlate throttle input
to flight speed, and
battery life can be
estimated based on the
necessary throttle input
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
41
Ground Station Power Test
• Purpose: Verify
ground station has
power for full two
hour test (DR2.2)
• Test: Connected all
externally powered
ground station
modules to power
supply and tested
longevity
• Results: Power
supplied for 230
minutes
3/4/2015
Mission Planner
Data Displays
Power supply
Ground station with mobile power supply
University of Colorado Boulder
Aerospace Engineering Sciences
42
SUV Cargo Test
• Procedure:
– Gather all ground station,
aircraft, and flight testing
components
– Position components within
an SUV with cargo dimensions
1.5x1x0.9 m
• If a larger SUV is used, the
proper dimensions will be
marked with tape
– Photograph configuration that
fits within the allotted space
• Purpose:
– Verifies DR1.7 and DR2.5: The
aircraft and ground station
can be transported in a cargo
volume of 1.5x1x0.9 m
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
43
Ground Dry Run –
Electronic Endurance
• Procedure:
–
–
–
–
Connect and power all ground station components
Start a timer once all units are turned on
Proceed to complete remaining ground dry run tasks
Continue use of ground station until timer reaches
110 minutes
• Purpose:
– Necessary to verify DR1.5: The demonstrations shall
be performed within 110 minutes
• Verifies the ground station can provide power for allotted
time
– Allows for flight tests to conclude before 110 minutes
which reduces the amount of time a pilot is needed
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
44
Ground Dry Run –
Proper Channel Communication
• Procedure:
– Connect and power all avionics units (no motor)
– Use RC transmitter to verify the servos are connected
to the right Pixhawk ports
– Hold aircraft in a user safe position
– Connect motor
– Tap throttle to confirm motor responds correctly
– Wait for propeller to stop moving, disconnect motor
from power
• Purpose:
– Verifies the proper avionics connections are made
– Also verifies that there are no faulty solder joints
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
45
Ground Dry Run –
Taking Data
• Procedure:
– Connect and power all avionics units (no
motor)
– Allow Pixhawk to gather data with all
electronic systems working
– Download data onto computer for analysis
following ground dry run
• Purpose:
– Verify DR2.1: Meet the required aircraft state
variable measurement accuracy
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
46
Ground Dry Run –
Transmitting and Displaying Data
• Procedure:
– Connect and power all avionics units (no motor) and
ground station components
– Establish communication between ground station
and aircraft
– Carry aircraft to maximum flight distance from
ground station
– Allow Pixhawk to collect and transmit aircraft state
variable data to ground station
– Use plotting script to display data on external
monitors in real time
• Purpose:
– Verify DR2.1, DR2.2, DR2.3: Transmit data in real
time, plot data at 10 Hz rate, and data display must
be observable by 10 people
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
47
Ground Dry Run –
Range Test
• Ground Dry Run – Range
• Procedure:
– Connect and power all avionics units (no motor)
– Establish communication between ground station and
aircraft
– Carry aircraft to maximum COA distance from ground
station (note: this is a larger distance than the maximum
flight distance)
– Command surface deflections with RC transmitter
– Command surface deflections with ground station
functions
• Purpose:
– Verifies the communications system has sufficient range
capabilities
– Reduces likelihood of lost link risk
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
48
Ground Dry Run –
Lost Link Protocol
• Procedure:
– Connect and power all avionics units (no motor)
– Establish communication between ground station
and aircraft
– Verify connection with surface deflection
commanded by ground station
– Disconnect communication system from aircraft
avionics suite
– Observe surface deflections as per predefined lost
link commands
• Purpose:
– Verifies that the lost link protocol has been properly
implemented
– Reduces likelihood of the aircraft taking an unsafe
flight path in the event of lost communications and
severity of losing communications
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
49
Ground Dry Run –
RC Override
• Procedure:
– Connect and power all avionics components (no
motor)
– Establish communication between ground station
and aircraft
– Command surface deflections with ground station
commands
– Use RC transmitter to command a different deflection
– Observe which surface deflection is performed
• Purpose:
– Verifies DR3.3: Pilot shall be able to take full control
of aircraft at any time
– Reduces severity of aircraft entering an undesirable
attitude
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
50
Ground Dry Run –
Video/LED Sync
• Procedure:
– Connect and power all avionics components (no motor)
– Establish communication between ground station and
aircraft
– Ensure video camera is recording data
– Command a function from ground station that drives the
LED
– Save data set from Pixhawk and video from camera
– On computer, match function command time to LED light
in video
• Purpose:
– Verifies DR4.2: Specific times in video can be correlated to
the correct data
• Verifies the LED is visible in daylight
• Proves that the sync procedure works
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
51
Ground Dry Run –
Battery Swap Time
• Procedure:
– Connect all avionics units
– Have team member walk aircraft to simulate a landing in the
proper location
– Start timer
– Have an additional team member, originally stationed at ground
station, gather and return the aircraft
– Open fuselage compartment, disconnect battery pack and replace
with a new battery pack
– Walk aircraft to takeoff location
– Stop timer
• Purpose:
– Necessary to verify DR1.5: The demonstrations shall be
performed within 110 minutes
• Provides time necessary to swap out battery (i.e. the time between
flights) which allows the total time of multiple flights to be determined
with only one flight
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
52
Backup Slides:
Requirements Satisfaction
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
53
Design Requirements from
FR1
FR1: A fixed-wing, conventional aircraft will individually demonstrate the phugoid, Dutch roll, and spiral modes in a
manner visible to a ground observer.
Requirement
ID
Description
Verified by Test
DR1.1
The roll, pitch, and yaw angles of the aircraft will be distinguishable to a ground observer
with 20/30 vision at a resolution of 5°. This defines the maximum range of demonstration as
200L for phugoid and spiral modes and 200b for Dutch roll mode, where L is the length of the
aircraft from tip to tail and b is the wingspan of the aircraft.
Flight test
DR1.2
The aircraft shall exhibit a phugoid mode with a pitch oscillation amplitude of at least 5
degrees, meeting minimum visibility requirement.
Flight Test
DR1.3
The aircraft shall exhibit a Dutch roll mode with a roll oscillation amplitude of at least 5
degrees, meeting minimum visibility requirement.
Flight Test
DR1.4
The aircraft shall exhibit a spiral mode with a yaw rotation of at least 180 degrees, or it shall
reach a roll angle that approaches an unrecoverable attitude, within a safety factor. The roll
angle that is defined as unrecoverable will be determined through simulations.
Flight Test
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
54
Design Requirements from
FR1
FR1: A fixed-wing, conventional aircraft will individually demonstrate the phugoid, Dutch roll, and spiral modes in a
manner visible to a ground observer.
Requirement
ID
Description
Verified by Test
DR1.5
The aircraft will be able to repeat the demonstration of all three modes in a period of 110
minutes (the duration of an ASEN 3128 lab) to at least 40 observers such that each
observer has the opportunity to view the ground station display at least 1 time.
Ground station
endurance test,
Battery change-out,
Flight Tests
DR1.6
The aircraft shall not exceed a reproducibility cost of $1,000.
DR1.7
The aircraft shall be stored in a container to be placed in an SUV with a cargo space no
greater than 150 cm x 100 cm x 90 cm.
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
N/A – Finances
SUV transport test
55
Design Requirements from
FR2
FR2: A ground station shall communicate with aircraft at all times and display live flight data of the aircraft
state variables.
Requirement
ID
Description
Verified by Test
DR2.1
The aircraft will measure and transmit flight data of its aircraft state in real-time
throughout its entire flight. The aircraft state measurements will abide to the following
resolutions: 1 m for position components, 1 m/s for velocity components, 1° for Euler
angles, and 1°/s for the angular rate components.
Sensor component
test
DR2.2
The ground station will process and output data of the aircraft state at a rate of at least
10 Hz.
Data display
component test
DR2.3
The ground station will produce a real-time, on-screen display of the aircraft state data
that will be visible to at least 10 observers on the ground.
Data display
component test
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
56
Design Requirements from
FR2
FR2: A ground station shall communicate with aircraft at all times and display live flight data of the aircraft
state variables.
Requirement
ID
Description
DR2.4
The ground station shall not exceed a reproducibility cost of $2,000.
DR2.5
The ground station must be stored in a conventional SUV with a cargo space no greater
than 150 cm x 100 cm x 90 cm.
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
Verified by Test
N/A – Finances
SUV transport test
57
Design Requirements from
FR3
FR3: The aircraft will function autonomously, and commands from the ground station will trigger mode
demonstrations and allow for a pilot to directly operate the aircraft via RC in the case of an anomaly.
Requirement
ID
Description
Verified by Test
DR3.1
The autopilot will allow the aircraft to fly in steady, level flight on a predetermined path
until it is commanded otherwise.
Flight Tests
DR3.2
The autopilot will return the aircraft to steady, level flight after the demonstration of
each mode.
Flight Tests
DR3.3
At any time during the flight, the RC pilot will be able to override the autopilot and give
the pilot direct control of the aircraft in case of an anomaly.
RC override test
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
58
Design Requirements from
FR4
FR4: An onboard camera will capture video of the flight of the aircraft.
Requirement
ID
Description
Verified by Test
DR4.1
The video will be stored onboard and downlinked after aircraft has landed.
Video camera
component test
DR4.2
The video will be able to be correlated with the mode demonstrations such
that the recorded flight data can be matched to specific times in the video.
Video/LED sync
test
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
59
Design Requirements from
FR5
FR5: The aircraft shall be capable of takeoff and landing without requiring modifications to the
flight environment and without suffering any damage that will impair operational capabilities.
Requirement
ID
Description
Verified by Test
DR5.1
The launch method will be appropriate for the test environment. The three
methods being considered are hand-launched, bungee-launched, and
ground take-off with landing gear. This will be highly dependent on the
selected airframe.
Flight test
DR5.2
The landing method will also be appropriate for the test environment.
Methods considered will include landing gear and controlled belly-landing.
This will be highly dependent on the selected airframe.
Landing simulation
tests,
Flight test
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
60
Level of Success 1
Success Requirement
Validated By
Autonomous mode
demonstrations
commanded by ground
station
2 of 3 modes demonstrated
Record flight data
3/4/2015
Flight Test
Flight Test
Sensor Component Test
University of Colorado Boulder
Aerospace Engineering Sciences
61
Level of Success 2
Success Requirement
All 3 modes demonstrated
Live data downlink and
display
Record flight video
Perform demonstrations in
110 minutes (1 lab period)
10 students can view
ground station
3/4/2015
Validated By
Flight Tests
Data Display Component
Test
Video Component and
Video/LED Sync Tests
Ground station endurance
test, Battery change-out,
Flight Tests
Data Display Component
Test
University of Colorado Boulder
Aerospace Engineering Sciences
62
Level of Success 3
Success Requirement
Fit aircraft and ground
station in SUV cargo bay
Validated By
SUV Transport Test
Reproducibility
Aircraft: $1,000
Ground Station: $2,000
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
Finances
63
Backup Slides: Budget
3/4/2015
University of Colorado Boulder
Aerospace Engineering Sciences
64
Purchases Breakdown
Category
Total
Aircraft
$939.88
Ground Station
$1265.61
Miscellaneous
$965.00
Testing
$109.78
Total
$3280.27
Overview
3/4/2015
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget &
Summary
65
Aircraft Breakdown
Overview
3/4/2015
Major Component
Total
Techpod
$186.70
Battery
$36.29
Servos
$90.95
Pixhawk
$383.90
Propulsion System
$84.17
Camera
$39.69
Small Components
$118.18
Total
$939.88
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget &
Summary
66
Ground Station Breakdown
Component
Total
Monitors
$395.16
Monitor Splitter
$149.99
Power Supplies
$324.23
RC Controller
$319.99
3DR Radio
$51.25
Cable
$24.99
Total
$1265.61
Overview
3/4/2015
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget &
Summary
67
Miscellaneous Breakdown
Overview
3/4/2015
Item
Total
FFR Printing
$154.92
Extra Batteries
$181.47
Extra Techpod
$186.70
NexSTAR
$144.99
NexSTAR Servos
$73.96
Manufacturing Needs
$37.55
Observer Medical Exam
$150.00
Other Items
$35.41
Total
$965.00
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget &
Summary
68
Test Breakdown
Category
Total
Servo Protractor
$17.99
Extra Propellers
$13.46
Static Thrust Stand
$78.33
Total
$109.78
Overview
3/4/2015
Schedule
Ground Testing
University of Colorado Boulder
Aerospace Engineering Sciences
Flight Testing
Budget &
Summary
69