LogDAT
Flight Data Logging
Sponsored by L3-Communications
Group 9
Group 9 Members
Winston James
EE
Brian Lichtman
CpE
Shaun Mosley
CpE
Tony Torres
CpE
Motivation
• L3-Communications uses a software set
(DATCOM) to calculate expected flight
characteristics of large fixed-wing aircrafts
• L3 has asked for a solution to verify the
accuracy of their software set when used
on small aerial vehicles
Project Objective
• Record vital parameters from test flights of
a model airplane
• Portable and easily adapted to other
aircrafts
• Provide easy way to obtain recorded data
and compare with L3’s software set
Specifications
• Ability to record data at speeds of at least
60 Hz
• Aircraft should be able to fly for at least
20 minutes while recording data
• Test vehicle must have a wingspan larger
than 3 feet
• Must not have more than ½lb weight
offset to one side
• Cost must be under $1500.00
Requirements
•
Lift Coefficient due to:
–
–
–
–
–
•
Drag Coefficient due to:
–
–
–
•
Sideslip (Cnâ)
Roll Rate derivative (Cnp)
Yaw Rate derivative (Cnr)
Pitching Moment Coefficient due to:
–
–
–
–
–
Basic Geometry (Cm)
Flap Deflection (Cmδf)
Elevator Deflection (Cmδe)
Pitch Rate derivative (Cmq)
Angle of Attack Rate derivative (Cmαdot)
•
Aileron Deflection (Clδa)
Sideslip (Clâ)
Roll Rate derivative (Clp)
Yaw Rate derivative (Clr)
Yawing Moment Coefficient
–
–
–
–
Basic geometry (CdD)
Flap deflection (Cδf)
Elevator deflection (Cdδe)
Side Force Coefficient due to:
Rolling Moment Coefficient due to:
–
–
–
–
Basic geometry (CLα)
Flap deflection (CLδf)
Elevator Deflection (CLδe)
Pitch Rate derivative (CLq)
Angle of Attack Rate derivative (CLαdot)
•
–
–
–
•
•
Aileron Deflection (Cyδa)
Sideslip (Cyâ)
Roll Rate derivative (Cyp)
Yaw Rate derivative (Cyr)
Misc
–
–
–
–
–
–
Horizontal Tail Downwash Angle (ε)
Derivative of Downwash Angle (δε/δα)
Elevator-surface hinge-moment
derivative with respect to alpha (Chα)
Elevator-surface hinge-moment
derivative due to elevator deflection
(Chδ)
Normal force coefficient (body axis) (CN)
Axial force coefficient (body axis) (CA)
External Components
Model Airplane
•
•
•
•
MQ9 Reaper – used by USAF, US Navy, CIA
Picked to meet L3’s request
Dimensions: 8.3 ft wingspan x 3.6 ft length
Price: $100.36
Autopilot
• Autopilot is installed on an aircraft to allow
for flight stabilization, auto takeoff, landing
and fixed flight patterns
• Basic units are GPS, accelerometer,
gyroscope, servos, telemetry
• Multiple types and brands are manufactured
Autopilot Selection
• ArduPilot Mega
– Open-source
firmware
– Relatively cheap
– Great community
support
– Free telemetry software
• Price: $415.00
• Before testing in actual flight, we will test
the ArduPilot in the FlightGear simulator
ArduPilot Software
Hardware and Firmware Integration
Hardware Design
• DYNAMIC PRESSURE “q” = 1/2ρV2
o Dependent on True Airspeed (TAS)
o Dependent on air density (rho)
o Dependent on AOA
• FORCE COEFFICIENTS
• TORQUES COEFFICIENTS
• TAS
o PITOT-TUBE PRINCIPLE
• AOA & AOS
o BOOM
HARDWARE BLOCK DIAGRAM
FORCE SENSORS
FORCE SENSORS
• MFGR: INTERLINK ELECTRONICS
• PN: FSR402
• THIN MEMBRANE TECHNOLOGY
• SMALL = 18.28mm DIAMETER
• LOW POWER = 2.5mW
• CHEAPEST SOLUTION
• FORCE RANGE: 0.352 oz. to 22lb!
ALTERNATIVE ZEBRA SYSTEM
FORCE SENSOR TERMINALS
Inertial Measurement Unit
Accelerometer
•
•
•
•
•
•
•
MFGR: ST MICROELECTRONICS
PN: AIS326DQTR
MET SPEC
• EXCELLENT BW
• SENSITIVITY
3-AXIS
SPI
LOW POWER= 2.64mW
HIGH SENSITIVITY: 1024LSB/G
0.977mm/s2 PER LSb
Gyroscope
•
•
•
•
•
•
•
•
ST MICROELECTRONICS
P/N: L3G4200DTR
MET SPEED REQUIREMENT:
• 1MHz > 60Hz
3-AXIS
SPI
LOW POWER: 18.91 mW
HIGH SENSITIVITY: 8.75 dps/lsb
FREE SAMPLES!
Inertial Measurement Unit
Boom Sensors
JUSTIFICATION
•
•
•
•
•
•
•
P/N: MPXV7002DP
RANGE: ±2 kPa
• REQ: +1.475 kPa dynamic
pressure = 50m/s velocity at
sea level
ACCURACY: 2mV/Pa
SAMPLED
ANALOG SENSOR
USED IN OTHER DRONE PROJECTS
LOW POWER = 50mW
Q= [Vout ±6.25%(Vs-2.5v)-0.5v]/ [0.2Vs]
JUSTIFICATION
•
•
•
•
•
•
•
MFGR: MURATA
P/N:SV01A103AEA01B00
LOW POWER: 5mW
LONG LIFE: 1M CYCLES
WIDE RANGE: 0-333º
VERY THIN
FREE!
BOOM SENSORS
Hardware: Humidity Sensor
HUMIDITY SENSOR
•
•
•
•
•
•
•
MFGR: HONEYWELL
P/N: HIH-5031-001
ANALOG SENSOR
LOW POWER= 1.65mW
SMALL SIZE
PURPOSE: AIR DENSITY
FREE!
TEMPERATURE SENSOR
•
•
•
•
•
•
MFGR: ANALOG DEVICES
P/N: AD7814ARMZ
SPI INTERFACE
LOW POWER =1.32mW
PURPOSE: AIR DENSITY
FREE!
BAROMETRIC PRESSURE
SENSOR
•
•
•
•
•
•
•
MFGR = BOSCH
P/N: BMP085
ANALOG SENSOR
LOW POWER = 0.03mW
ALTITUDE RANGE: 0 to
29,528ft (9000m)
ACCURACY: ±100Pa ±27ft
= ±8.22m
PURPOSE: AIR DENSITY
ALTITUDE SENSORY
POWER SUPPLY
MCU
Microcontroller Unit (MCU)
Selection
• MCU Chosen
– Microchip’s dsPIC33EP512MU810
• Aspects reviewed were:
– Does it meet our I/O requirements?
– What programming and debugging resources
are available?
– What kind of support is available for the
MCU?
– Can we get free samples of the products?
I/O Requirements
• I/O Requirements:
– 34 Analog I/O
•
•
•
•
30x Force Sensors
2x Angle Sensors
1x Differential Pressure Sensor
1x Humidity Sensor
FSR 402 Force Sensor
– 4 SPI (Serial Peripheral Interface) Digital I/O
•
•
•
•
Accelerometer
Gyroscope
Temperature Sensor
SD Card Interface
– 1 I2C (Inter-Integrated Circuit) Digital I/O
• Barometric Pressure Sensor
MCU Programming and Debugging
Environment
• Free academic version of their C compiler
and debugger with graphical IDE
– Includes code optimization not available in
the normal free version.
– Fully functional with all libraries and source
code of commercial version
• Memory Disk Drive File System Library
• Multi-level code optimization
Available Support
• There is abundant documentation for the
use of dsPic33s
• Large collection of online training videos
provided by Microchip
• Online 24hr support system for technical
support along with a large support forum
community
• Large collection of example code
Sample Availability
• 3 dsPIC33EP512MU810
MCUs
• 2 Free Samples of the ICD3
• 2 Free Samples of the
Explorer 16 development
board
• 2 Free Samples of
dsPIC33EP512MU810
daughter boards for use
with the development
boards
MCU Software Design
• Software will be split into two separate
sections:
– Data acquisition
– Data storage
Data Acquisition
• The MCU firmware will be designed to poll
sensors at a minimum rate of 60hz.
1. Grab data from sensor
•
•
The analog sensors will be read 4 at a time
Digital sensors will be read sequentially
2. Convert each sensor value to an IEEE floating
point number
3. Send data to data storage buffer
4. Repeat until all 38 sensors have been read
Data Storage
• Using the file system library from
Microchip, an SPI interface will be used to
communicate with an SD card.
• A data storage buffer will wait until 38
values are received
• Once this occurs, the buffer will be flushed
to the SD card as raw binary
PCB LAYOUT
Power Consumption
PART NUMBER
SENSORS
L3G4200DTR
3D GYRO
MAX POWER
(mW)
AIS326DQTR
Vdd (V)
Idd (mA)
18.91
3.1
6.1
2.211
3.3
0.67
1.32
3.3
0.4
1.65
3.3
0.5
80
5
0.5
50
5
10
0.03
2.5
0.012
4
5
0.05
1980
3.3
840
0.4
5
0.02
5
5
1
3D ACCELEROMETER
AD7814
TEMPERATURE
SENSOR
HIH-5031-001
HUMIDITY SENSOR
FSR402
FORCE SENSOR
MPXV7002DP
DIFFERENTIAL PRESSURE
SENSOR
BMP085
ABSOLUTE PRESSURE
SENSOR
OPA244UA
AMPLIFIER
DSPIC33EP512MU810
MCU
SN74LV4051APWR
8 CHANNEL MUX
SV01A103AEA01B00
SMD HOLE ANGLE
SENSOR 333 DEG
TOTALS FOR
LOAD
2143.521 mW
859.252 mA
MAX power handling
ADP3338AKCZ-3.3RL7
3300
3.3
1000
5000
5
1000
3.3v supply
ADP3338AKCZ-5-R7
5v supply
SUPPLY
CAPABILITIES
8300 mW
2000 mA
Software Design
Software Overview
• Graphical User Interface (GUI)
– The GUI is a simple interface to make the file
selection process much simpler than using the
command prompt.
• Program execution
– The program will execute after the "Create"
button is clicked. From there it will perform all
the functions that need to take place to
translate the input data to readable data for
the user.
Data Structures
• I choose to use a linked list for memory
concerns
– Linked List
• Can only access the next value
• Is the exact length of the data and only adds one
at a time
• With only one node being made at a time
a linked list insures the minimum amount
of memory being taken.
GUI
• Source text box is to specify
the source file location
• Destination text box is to
specify the name and
destination of the file to be
created
• The create button will run
the computations to do the
conversion from a binary to
a csv file
Software Design
• Required measurements
o Parsed Data
 Forces
q
 Angle of Attack
o Derivatives
o Moments
o Calculated measurements
o
o
Force and moment Coefficients
Coefficients due to different parameter on the plane
o CL due to AOA
Software Design
• Derivatives
– The derivatives are found by finding the slope between the
two points on ether side
– Because we need to find second derivatives that makes the
first and last 2 data points not accurate.
𝑦 −𝑦
• 𝑚2 =
• 𝑚2 =
• 𝑚2 =
𝑦 −𝑦
𝑥2 −𝑥1 ∗ 𝑥2 −𝑥 1 + 𝑥3 −𝑥2 𝑥3 −𝑥 2
2 1
3 2
𝑥2 −𝑥1 + 𝑥3 −𝑥2
𝑦2 −𝑦1 +𝑦3 −𝑦2
𝑥2 −𝑥1 +𝑥3 −𝑥2
𝑦3 −𝑦1
𝑥3 −𝑥1
Software Formulas
Rz =
Rx =
𝐶𝑜𝑠 ∝ −𝑠𝑖𝑛 ∝
𝑠𝑖𝑛 ∝ 𝑐𝑜𝑠 ∝
0
0
0
0
1
0
0
0
0
𝑐𝑜𝑠β
𝑠𝑖𝑛β
0
0
0
1
0
0
−𝑠𝑖𝑛β
𝑐𝑜𝑠β
0
0
0
0
1
0
0
0
1
Ry =
𝐶𝑜𝑠𝟇
0
−𝑠𝑖𝑛𝟇
0
0 𝑠𝑖𝑛𝟇
1
0
0 𝑐𝑜𝑠𝟇
0
0
Rz ∙ 𝑅𝑥 ∙ 𝑅𝑦 ∙ 𝐹
0
0
0
1
F=
𝑥
𝑦
𝑧
1
Formulas for Coefficients
Forces
𝐿𝑖𝑓𝑡 = 𝑚𝑎𝑧 𝑠𝑖𝑛(90 − 𝛼)
𝐷𝑟𝑎𝑔 = 𝑚𝑎−𝑥 𝐶𝑜𝑠 90 − 𝛼
𝑆𝑖𝑑𝑒 𝐹𝑜𝑟𝑐𝑒 = 𝑚𝑎𝑦
𝛼 𝑖𝑠 𝐴𝑂𝐴
True Air Speed
𝑉=
2𝑞
𝜌
𝜏𝑥,𝑦,𝑧
𝑑𝜔𝑥,𝑦,𝑧
= 𝐼𝑥,𝑦,𝑧
𝑑𝑥
𝐼 is experimentally determined
Torque Coefficient Definition
Force Coefficient Definition
𝐿𝑖𝑓𝑡
𝐶𝑙 = 2 ∗
𝑞𝐴
𝐷𝑟𝑎𝑔
𝐶𝑑 = 2 ∗
𝑞𝐴
𝑆𝑖𝑑𝑒 𝐹𝑜𝑟𝑐𝑒
𝐶𝑠𝑖𝑑𝑒 𝑠𝑙𝑖𝑝 = 2 ∗
𝑞𝐴
A is reference area
Torques
𝐶𝑝𝑖𝑡𝑐ℎ =
𝜏𝑦 /𝑞𝐴𝑙
𝐶𝑟𝑜𝑙𝑙 =
𝜏𝑥 /𝑞𝐴𝑙
𝐶𝑦𝑎𝑤 =
𝜏𝑧 /𝑞𝐴𝑙
Air Density
𝑝
𝜌=
𝑅𝑇
A is reference area, l is application length
Administrative
Budget
Cost Totals
Other
Parts/Labor
25%
Sensor Parts
15%
Plane Parts
25%
Autopilot Parts
35%
Plane Parts
Autopilot Parts
Sensor Parts
Other Parts/Labor
Parts List Group
Plane Parts
Autopilot Parts
Sensor Parts
Other Parts/Labor
Overall Cost
TOTAL
$301.88
$424.95
$186.07
$296.24
$1209.14
Work Distribution
Winston J. Hardware and power consumption
Brian L.
Data handling and help with data acquistion
Shaun M.
Autopilot and data acquisition
Tony T.
User software application
Questions