Michael Bova- Project Lead Kevin Alderfer- Lead Engineer Ryan Selig- Hardware Engineer P13015- Navigation Aid for Visually-Impaired
Dec 26, 2015
Michael Bova- Project LeadKevin Alderfer- Lead Engineer
Ryan Selig- Hardware Engineer
P13015-Navigation Aid for Visually-
Impaired
eZ430-RF2500
Why choose new design?
Benefits
Easier integration of transceiver into design
Controllable output power/read range for each tag/node
Lower power consumptionOn-board antennasFuture improvements: Can transmit
more data than just an ID
New Challenges
Redesigning the PCBUpdating software to utilize eZ430-
RF2500Staying under budgetCreating battery packs
Software
UML Functional Diagram (for each system below):
Main MSP430ReceiverTransmitter
Navigation Functional Diagram
Map Data Structures
h
Magnetometer Function Diagram
Access Point
End Device
Programmable Output Power
Output Power (dBm)
Read Range (m) Operating Voltage (V)
0 34 3.2
-20 10 2.7
-26 3-4 2.5
-28 1.5-3 2.5
-30 0.5-1 2.5
Hardware
Existing Design (block diagram)Changes neededProposed new design (block diagram)Proposed schematic/PCB for eZ430-
RF2500 interfaceRange limiting/funneling
Changes Made / Considered
Removed RFID H10223 connector
Removed LT1930 switching regulatorIncrease in Voltage no longer necessary due to
RFID removal
Consider adding Germanium diode between Li-Ion battery and Access Point for miniscule Voltage decrease (~0.2V)
Demos
eZ430-RF2500 network with different output powers
Input/Output (Keypad/Motors)
Task Management If design is done, order PCB by end of Finals week and eZ430s(Fall quarter). Update map file (Week 1) Purchase supplies for battery packs (Week 1) Update transmitting data (from temperatures to IDs) (Week 2) Test PCB from fab (Week 2) Assemble battery packs (Week 3) Replace reader code with eZ430 code (Week 4) Program each individual end device (Week 4) Test communication between nodes and receiver after integration (Week 5) Fix magnetometer code (Week 6) Test/improve path following (Week 7) Test/improve path finding (time permitted) Full system testing (Week 8) Write technical paper (Week 9) Create final product poster board (Week 10) Demo (Week 10)
Bill of Materials
Item Quantity Cost
eZ430-RF2500t 8 $160
eZ430-RF2500t 2 Borrowed
AAA batteries 20 $7.97
PCB Prototype 3 ($5/in^2)
AAA Battery Holder 10 $15.00 Battery/Spy-Bi-Wire connector 10 ?
Keypad 1 Inhereted
Magnetometer 1 Inhereted
Motors 4 Inhereted
Lithium Ion Battery 1 Inhereted
MSP430 Dev Kit 1 Borrowed
Sleeve 1 Inhereted
Plastic Housing 1 Inhereted
Major Risks
Not receiving PCB on scheduleFailing to meet customer
demands/deadlines due to reduced team size
Staying under budgetGauging workload incorrectly
Questions? Comments? Concerns?
Thank you for your feedback!