1. Thermal Detecting Wireless Sensor Network
Presenters: Joseph Roberson, Gautam Ankala, and Jessica Curry
Faculty Advisor: Dr. Linda Milor
ECE 4007: Preliminary Design Review
Georgia Institute of Technology
School of Electrical and Computer Engineering
October 21, 2008

2. Project Overview
Monitor continuously thermal activity in environmental areas such as wildlife and forests. Detect hazardous thermal conditions using Crossbow motes and onboard sensors
Projected cost of one unit is $2500, which includes four wireless sensors, software, and programming board. Primary consumer is wildlife and forest agencies
Program motes with algorithm that efficiently routes data through wireless sensor network
Transmit real-time data wirelessly to computer base station for analysis and response to threatening conditions

3. Design Objectives Monitor outdoor area up to 10,000 square meters
Detect hazardous thermal activity with onboard heat sensors
Program with energy efficient algorithm
Wirelessly transfer data readings from sensors to computer
Provide a basic structure for research groups focused on energy efficient wireless networks

4. Explanation & Illustration of Design
Transceiver node
Communicate with PC
Receive information packet from nodes
Transmit or receive data
Intermediate Nodes
Forward data from transmitter to receiver
Send information packets periodically 4

5. Hardware Components MICAz (Wireless unit) Low power Frequency: 2.4GHz
Distance range: 20m-30m
3 programmable slots
3 LED lights (red, green, yellow)‏
MTS400 (Sensor board)
Light intensity: lux (lm/m2)
Temperature 65 degrees
Spectral responsivity: 400 – 1000 nm
51pin connector for MICAz
MIB520 (Programming board)‏
USB cable for PC connection 5

6. Software Components TinyOS
TinyOS for all mote class devices is the actual operating system
A flexible mesh networking protocol in TinyOS called XMesh has been developed by Crossbow Technology, Inc
MoteWorks
Provides different applications (e.g. Programmer’s Notepad) for editing and compiling codes
Provides a library of programs written in nesC 6

7. Hidden Terminal Problem
Collision A B C
A talks to B
C senses the channel
C does not hear A’s transmission (out of range)‏
C talks to B
Signals from A and B collide 7

8. CSMA/CA (CSMA with collision Avoidance)
Ensures that each sensor transmits data at a specific time
Nodes ready to transmit listen to the channel to check for any activity
If the channel is idle the node receives permission to transmit
If the channel is busy the node has to defer its transmission for a random interval of time until it receives permission to transmit

9. Acceptance Test Cases Expected results Any 1 sensor receives heat
Data will be routed to PC through Sensor 4
Any combination of 2 sensors receives heat
Data will be routed to PC through Sensor 4 implementing CSMA
Any combination of 3 sensors receives heat
All 4 sensors receive heat
No sensors receive heat
No data will be routed

10. Problems and Issues with Design
Hardware issue
Locating the correct port ID number for communication between PC and sensors
Poor connection of USB cable to PC
Time delay when testing information packets sent from two intermediate nodes
Varying the time interval between consecutive information packets by changing the clock frequencies
Considerable difference in language of nesC from C/Java
Study tutorials from official website
Make use of available codes provided in the MoteWorks library

11. Project Schedule and Future Work
Tasks
Deadline
Identify sensor types
September 10, 2008
Configure sensor layout
September 20, 2008
Determine routing algorithm
TinyOS tutorials
October 20, 2008
Interface all sensors with PC
November 17, 2008
Verify data transfer from sensors to PC
November 20, 2008
Verify correct data values

12. Current Status of Project
TinyOS software downloaded and operational on each PC
Successful completion of tutorials on TinyOS website
Currently programming the sensors to PC

13. Questions