View
216
Download
0
Category
Preview:
Citation preview
Detailed Design Review
P10231 - UAV Telemetry
Chris Barrett Project Manager
Gregg Golembeski Interface Manager
Alvaro Prieto Radio Concepts
Cameron Bosnic Software Concepts
Daron Bell Power Concepts
R09230 Project Family
Mission Statement
Customer Needs
Deliverable Summary
System Architecture
Subsystem Design
Bill of Materials
Risk Assessment
Outline
Mission StatementThe goal of this project is to create an open source, multi platform, bidirectional telemetry system.
Carried on UAV Airframe C
Interface with Control System(P10236)
Send flight data to ground
Remotely Trigger On-Board Camera
Deliverables
Wireless System for Bidirectional Communicationbetween control system and ground PC
GUI Application that displays flight datamulti platform, open-source, in real-time
System Design
RadioGoals:
Two radios that send and receive data with high throughput and data integrity.
The radios should be transparent to both the control system and base station as if it were a physical connection.This “radio as a wire” concept allows interchangeability of various radios using different wireless technologies.
RadioComponents
Radio: 2 Digi Xtends PKG 900 MHz.
Ground Antenna: 65’’ 8.1 dBi Omni-directional antenna.
UAV Antenna: 6’’ 2.1 dBi Omni-directional antenna.
Specifications
Engineering Specifications
Ideal Value Marginal Value
Range 3000 2000
Refresh Rate (Hz) 10 5
Analysisc Speed of Light
L Wavelength
f Frequency
Pr Power Received
Pt Power Transmitted
Gr Receiving Antenna Gain
Gt Transmitting Antenna Gain
R Distance Between Antennas
AnalysisCalculated Values
Range 115200
bps
Range 9600 bps
Refresh Rate 115200 bps
Refresh rate9600 bps
Max Packet size
1400 4600 137 11
Min Packet Size
1400 4600 320 26
TestingTransfer of Serial Data:
• Connect computer to each radio
• Transmit data using simple terminal program
• Tester confirms data is accurate
• Repeat at both available baud rates to confirm proper
orientation
TestingRange:
• Place one radio in a high place and the another on a mobile platform
• Send data back and forth between the radios using an automated program
• Move away with the mobile radio until you can no longer receive data.
InterfaceRadio >> Controller
• DB 9 M/F cable Molded
Radio >> Computer
• Serial Cable
• USB to Serial Adapter
Power SupplyPower solution must...
not interfere with other on-board power systems.
sustain radio communication throughout flight time.
Components:Battery: 11.1V 5500mAh Li-Poly Lipo
Battery Pack
SpecificationsEngineering Specifications
Ideal Value Marginal Value
Flight Time (min) 45 30
Design SpecsMin. Battery Charge rating (mA-
h)900
AnalysisCurrent requirement for radio:
Battery Current mA x Time hours=mAh900 mA x 1 Hour=900 mAH
Battery Life:
Battery Current Rating /Current Draw = Run Time 5500 mAh/900 mA=6.11 hours
Testing•Battery Life:
• Connect battery across a ten ohm resistor and monitor its output voltage until it drops below the level that is accepted by the radio
• The time it takes the voltage to drop below the acceptable amount is the approximate run time of the battery
InterfaceBattery >>Radio:
•Barrell power connector , size type M (5.5mm x 2.1mm barrell type connector)
•Battery output cables will be soldered to connector
Mounting and PackagingThe Mounting and Packaging solution must...
securely attach the aerial radio and power systems to UAV C.
provide protection to onboard components in the event of a hard landing.
add minimal weight to the system.
add minimal size to the system.
allow for easy access to components.
Mounting and Packaging
1.5 in in
2 in.
1.13 in.
0.125 in
SpecificationsEngineering Specifications
Ideal Value Marginal Value
Weight (kg) 0.5 2.27
Size (cm) 15.25x15.25x15.25 17.75x17.75x17.75
Flight Time (min) 45 30
Max Acceleration(m/s2)
567 56.7
Design Specifications
Associated ES
Max Stress (kPa) 2.82e5 Max Acceleration
Max Weight (kg) 2.27 Weight
Max Size (cm) 17.75x17.75x17.75
Size
Max Temp.(ºC) 80 Flight time
Analysis
•Assumptions:o Motion of system is considered to be free vibrationoFoam acts a linear springoPCB in radio is analogous to PCBs used in phonesom1 and m2 are homogenousoDamping can be neglectedoCan simplify to a system with two degrees of freedom
m1 = 0.2 kgm2 = 0.364 kgk1 = 1310 N/mmk2 = 592 N/mmVi = 6 m/s
AnalysisFBD 1 FBD 2
Equations of motion Mass and stiffness Matrices
Kt = M-1/2KM-1/2
Normalized stiffness Matrices
w = [w1 w2]T
Natural Frequency Matrix Eigenvector Matrix
P = [v1 v2]
Analysis. Initial conditions for modal coordinates
Displacement of modal coordinates
Displacement ResponseDisplacement Response
Analysis.
Eg=2700 Jmradio=0.2kgmax=42.2 C
Eg = mcpT
Radio
Eg
Max Temperature:
Assumptions:
o Radio is well insulated
o Energy usage is 1 Watt
o Ambient Temperature is 37.8 C
o Run time is 45 minutes
Insulation
Testing. Overheating:
• Run the system in an environment that is insulated similarly to our system.
• Monitor the temperature of the radio while it is running.
• If the radio stays within its operating temperature for longer then the planned flight time we can be sure it will not overheat in the UAV.
Interfaces. •System >> UAV C
•System will be attached to UAV C using Industrial strength Velcro.
•Housing >>Battery/Radio
•Industrial strength Velcro will be used to secure the battery/radio to the housing
SoftwareSoftware application must...
track and log UAV control variables.
support multiple computing platforms.
report all flight data through a visual interface.
maintain open source concepts.refresh at acceptable rate.
transmit remote shutter command.
Software Design
GUI Design
Flight Plan
GUI Design
Flight Info
GUI Design
Data View
Bill of Materials
Bill of Materials
Recommended