LogDATFlight 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:

– Basic geometry (CLα)– Flap deflection (CLδf)– Elevator Deflection (CLδe)– Pitch Rate derivative (CLq)– Angle of Attack Rate derivative (CLαdot)

• Drag Coefficient due to:– Basic geometry (CdD)– Flap deflection (Cδf)– Elevator deflection (Cdδe)

• Side Force 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)

• Rolling Moment Coefficient due to:– Aileron Deflection (Clδa)– Sideslip (Clâ)– Roll Rate derivative (Clp)– Yaw Rate derivative (Clr)

• Yawing Moment Coefficient– 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

• TASo PITOT-TUBE PRINCIPLE

• AOA & AOSo BOOM

HARDWARE BLOCK DIAGRAM

FORCE SENSORSFORCE 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

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

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

JUSTIFICATION• MFGR: MURATA• P/N:SV01A103AEA01B00• LOW POWER: 5mW• LONG LIFE: 1M CYCLES• WIDE RANGE: 0-333º• VERY THIN• FREE!

Q= [Vout ±6.25%(Vs-2.5v)-0.5v]/ [0.2Vs]

BOOM SENSORS

Hardware: Humidity SensorHUMIDITY 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

– 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

FSR 402 Force 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 buffer4. 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

Pow

er C

onsu

mpti

onPART NUMBER SENSORS

MAX POWER (mW)

Vdd (V) Idd (mA)

L3G4200DTR 3D GYRO 18.91 3.1 6.1

AIS326DQTR3D ACCELEROMETER

2.211 3.3 0.67

AD7814TEMPERATURESENSOR

1.32 3.3 0.4

HIH-5031-001 HUMIDITY SENSOR 1.65 3.3 0.5

FSR402 FORCE SENSOR80 5 0.5

MPXV7002DPDIFFERENTIAL PRESSURESENSOR

50 5 10

BMP085ABSOLUTE PRESSURESENSOR

0.03 2.5 0.012

OPA244UA AMPLIFIER4 5 0.05

DSPIC33EP512MU810 MCU1980 3.3 840

SN74LV4051APWR 8 CHANNEL MUX0.4 5 0.02

SV01A103AEA01B00SMD HOLE ANGLE SENSOR 333 DEG

 5 5  1

TOTALS FOR LOAD

  2143.521 mW   859.252 mA

    MAX power handling

ADP3338AKCZ-3.3RL73.3v supply

3300 3.3 1000

ADP3338AKCZ-5-R75v supply

5000 5 1000

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 measurementso Parsed Data

Forces q Angle of Attack

o Derivativeso Momentso Calculated measurements

o Force and moment Coefficientso 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.

Software Formulas

𝐶𝑜𝑠∝ −𝑠𝑖𝑛∝ 0 0𝑠𝑖𝑛∝ 𝑐𝑜𝑠∝ 0 00 0 1 00 0 0 1

Rz =

𝐶𝑜𝑠𝟇 0 𝑠𝑖𝑛𝟇 00 1 0 0

−𝑠𝑖𝑛𝟇 0 𝑐𝑜𝑠𝟇 00 0 0 1

Ry =

1 0 0 00 𝑐𝑜𝑠 β −𝑠𝑖𝑛 β 00 𝑠𝑖𝑛 β 𝑐𝑜𝑠 β 00 0 0 1

Rx =

𝑥𝑦𝑧1

F=

Rz ∙𝑅𝑥 ∙𝑅𝑦 ∙𝐹

Formulas for CoefficientsForces Torques

is experimentally determined

Force Coefficient DefinitionA is reference area

Torque Coefficient DefinitionA is reference area, l is application length

True Air Speed

Air Density

Administrative

Budget

Parts List Group TOTAL

Plane Parts $301.88Autopilot Parts $424.95Sensor Parts $186.07Other Parts/Labor $296.24 Overall Cost $1209.14

Plane Parts25%

Autopilot Parts35%

Sen-sor

Parts15%

Other Parts/Labor25%

Cost Totals

Plane PartsAutopilot PartsSensor PartsOther Parts/Labor

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