FlyNet

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Ben Houston
Camden Mendiola
Dan “Klitz” Johnson
Dan Rice
Monty Prekeris
To provide a flexible low power wireless
aerial/terrestrial network that allows the
user to survey, sense, and respond.
 Useful for military, police, search and
rescue, and/or back country navigation
 Localized and self managed.

Camden
To design and implement an autonomous
quad-copter platform that can remotely sense
and relay data to a base station
 To utilize the IEEE 802.15.4 protocol to create
a low power mesh network

Camden
Camden
Motors
XBee
Command
Station
PC
Quad-copter
ATMega
2560
Environmental
Sensors
Flight
Sensors
& GPS
Command
Station
XBee
Motors
XBee
Third Comm
Module
Flight
Sensors
& GPS
Environmental
Sensors
Camden
SECONDARY GOAL
Manual
Flight
Command
Locate
unoccupied
air space
Perform
Autonomous
Flight Pattern
Manual
Return Flight
Perform
Autonomous
Flight
Pattern
Autonomous
Return
Navigation
ELEVATED GOAL
Assert UAV
Mode and
Input GPS
Point
Autonomous
Navigation
to GPS Point
Camden
Command Station
WINDOWS OS PC
USB
• XBee PRO ZB
• 2.4GHz RF
• 3.2 km range
• 250 Kbps data throughput
• XBee Explorer USB
IEEE 802.15.4
Zigbee Protocol
Dan J.
Motors
• E-Flight Brushless
• 1020Kv
• 22A max continuous
• 2lb nominal
payload/motor
Motors
ESC
ZigBee
XBee
(Serial)
30A ESC’s:
• Allows 35,000 rpm
• 40A for 10s Burst
• PWM
Copter
ATMEGA
2560
Flight
Sensors
Flight Sensors:
• Barometer – BMP085
• Magnetometer – HMC5843
• Accelerometer – ADXL345
• Gyro – ITG3200
• Ultrasonic range finder – Daventech SFR10
• GPS – USGlobalSat EM-408
• I2C
Env.
Sensors
Environmental Sensors (tentative):
• Temperature
• Gas
• CMOS Camera - TCM8230MD
Dan J.

Terrestrial Unit
 Temperature
 Chemical Sensing
 Person
○ Heart Rate

Second Quad Copter
 Mirror functionality of former
Quad-Copters
Dan J.
• Battery – 11.1 V, 8000mAh High Discharge Li-Po Battery
• Power Rails – 5V rail for the ATMega 2560, 3.3V for Sensors and XBee
• MC33269 Voltage Regulator – takes 12V to 5V
• Logic Level converter – converts 5V to 3.3V for input to XBee and 3.3V to 5V for
signals output from XBee
• Battery Monitor – checks the status of the battery voltage and signals a
warning if it is too low. If the battery supply voltage drops even further, the
Quadcopter will begin to land.
• ESCs (Electronic Speed Controller) – Convert PWM signals from the
ATMega2560 into signals for the brushless motors.
Dan J.
Flight Sensors(Primary):
• Barometer – Used to measure atmospheric pressure. Allows the flight control to determine
height of the Quadcopter and attempt to increase power to motors in order to maintain altitude.
•
Magnetometer – Measures the strength of the Earth’s magnet field to get the heading of the
Quadcopter
•
Accelerometer – Measures acceleration of the Quadcopter along the x, y, z axes.
•
Gyro – Measures radial velocity in terms of roll, pitch, and yaw.
Flight Sensors(Secondary):
• Ultrasonic range finder – Determines distance objects are away from the sensor. Can be used to
avoid objects that come within range of the Quadcopter. Can also be used to aid in landing.
•
GPS – Gets longitude and latitude coordinates from a satellite which allows the Quadcopter to
determine a flight path to its desired location
Dan J.
• Temperature Sensor – Analog output. (Primary)
• Gas Sensors – CO, Methane, Hydrogen gas. Analog Output. (Elevated)
• CMOS Camera – Communicates using I2C. (Elevated)
• Heart rate monitor – Uses a Polar transmitter and communicates through
I2C. (Elevated)
Dan R.



Ultrasonic
 Multiple Ultrasonic sensors may cause interference with one another
○ Alternate sets of opposing sensors to fire at different times.
 Wide beam width may cause unexpected detection
○ Size down the beam width and use more sensors
 Motor interference
○ Relocate sensors
Barometer
 Propeller interfering with air pressure
○ Encapsulate barometer or shield it from motors
CMOS Camera
 Exceed XBee bandwidth
○ Use high compression
○ Stream at lower frames per second
○ Store images locally
Dan R.
Ben
Ad hoc On-demand Distance Vector (AODV) Mesh Routing



Allows data packets to traverse multiple nodes (hops) from
source to destination
Does not necessarily have to be routed through the coordinator
AODV Routing Algorithm dictates ever changing and locally
stored look up table of nearest one hop neighbors
Ben
Digi International has designed the Xbees in a way that allows a
PAN to include up to 40 drop-in radio devices in an Ad Hoc
configuration.
 Ease of use when building a large self healing network.

Ben







ZB Pro RF data throughput: 250 kbps
Line of site range: 3.2 km
Serial Flow Control via RTS and CTS pins
Encryption (adds latency)
Sleep Mode(s)
Ability to self manage digital and analog sensors
Application Program Interface
Ben
The API specifies how commands, command responses and module status
messages are sent and received from the module using a UART Data Frame.




Follows IEEE 802.15.4 standard
Useful for software design
84 byte payload
Multiple command features
Ben
Software drivers contain algorithms that
can build or parse API packets
 Payloads can contain the following data:

 Radio Addresses
 12 bits of analog sensor data converted to
digital at the XBee hardware level
 Command Status bytes
 AT commands

Embedded System Experience
Ben

Risks





Signal Interference
Range
Power Consumption
Bandwidth
Contingency
 XBee-PRO® ZB Wall Routers
○ Extends signal strength and range of an XBee ZB mesh
network
○ Creates additional network pathways for more reliable
mesh networking
 Adjust Sleep Mode settings via XBee firmware
 Limit amount of simultaneous data output
Ben
ATmega2560














Operating Voltage: 5V
JTAG Interface
Digital I/O Pins: 54 (of which 14 provide PWM output)
ADC Pins: 16
UART Ports: 4
SPI Interface
I2C Interface
2 External Interrupt Pins
DC Current per I/O Pin 40 mA
DC Current for 3.3V Pin 50 mA
Flash Memory: 256 KB of which 8 KB used by bootloader
SRAM: 8 KB
EEPROM: 4 KB
Clock Speed: 16 MHz
Monty

Eclipse C/C++ Dev environment for
Arduino Mega
 Allows for parallel development of flight
programs and control during PCB development

ATMEL Professional Dev Suite intended
for low level debugging though JTAG
 Need access to JTAG pin outs which the
Arduino Mega does not give access to
 Emulator AVR JTAG ICE
device will be used
Monty

200Hz
• Read Gyro
• Read Accelerometer

100Hz
• Flight Controls (Stabilization routines)

50Hz
• Process Telemetry

25Hz
• Read Barometer

10Hz
• Read Battery
• Process Compass
Monty
ATmega
PID
MOTORS
SENSOR
RESPONSE
Monty

Task Scheduling – Addition of sensors
consumes clock cycles
 Scheduling sensors in order of priority
 Circumvent processer and straight to XBee
 Co-Processor
 Hard Real Time System – Sam
Monty
• Prototype Frame:
Made from Balsa, Poplar and Oak.
• Aluminum Frame:
Aeroquad frame that is more robust.
• Future Frames:
A Carbon Fiber or Fiberglass
frame could be used, as these are lightweight
at the risk of durability
Dan R.
Indoor net and pulley
apparatus
 Emergency Shutoff via
firmware watchdog timer
 Manual Emergency
shutoff via a serial
command

Dan R.
Phase 1:
PCB Design
Flight Command
Ben Camden Daniel Klitz Monty
Phase 2:
PCB Revision and Design
Environmental Sensor
*Hardware design
*Software design
XBee Mesh Network
Phase 3:
Basic Auto Patterns
GPS Integration
Dan R.
Dan R.
• Frame
• Plan to buy Aluminum frame in the future. If it is not
available, we may have to make it ourselves.
• Schedule uncertainty
• Current timeline does not incorporate weekends.
• Availability of components
• Utilize multiple distributers
• Code Sharing
• Tortoise SVN with revision control
• Broken Parts
• Backup Parts on hand (Propellers)
Dan R.
Component
#
Price
E-Flite 480 Brushless Motors
4
$54 each
Hobbywing Pentium 30A ESCs
4
$23 each
Accelerometer ADXL-345
1
$15
Magnetometer HMC-5843
1
$15
Barometer BMP-085
1
$20
Gyro ITG-3200
1
$50
XBee ZB Pro 2.4GHz
3
$40 each
Arduino Mega2560 Temp Dev. Boards
2
$50 each
Safe Testing Apparatus
1
$75
8000 mAH LiPo Battery
1
$55
Revision 1 Frame Materials
1
$30
Revision 2 Aluminum Frame
1
$225
PCB Orders
3
$65 each
ATMega 2560 QFP Processors
2
$20 each
US GlobalSat EM-408 GPS Module
1
Free, Thanks Nate Bernstein
Other Sensors (Gas, Heartrate, Camera, etc)
1
$20 - $100 each
Dan R.
Component
#
Price
Other SMT Board Components
3
$50 each
Total (Not including tentative high level sensors)
~ $1400
Funding:
-UROP
-EEF (possible)
-Sponsorship through Elintrix
Dan R.
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