LizardNet

1
LizardNet

• Kapambwe Kangombe
• September 1st 2005

2
Presentation outline

• Introduction motivation goal
• The hardware and software
• Overview of what our team did
• Deployment
• Results future
• Writing a driver process example
• Acknowledgments

3
Motivation

• Mike wanted to experiment with wireless sensor
  networks.
• Biology department wanted a better way of
  collecting data for studying lizard
  thermo-regulation, that is
• less time consuming
• less invasive
• AND a lot more data points

4
Project goal
To build and deploy a non-invasive wireless
sensor network (at the Bernard Field Station) to
measure temperature. Thereby saving biologists
studying lizard thermo-regulation time in
collecting data from the field and providing a
much larger (better) data set than usual. But of
course as computer scientists we just wanted to
play with a wireless sensor network.
5
the hardware MicaZ
MicaZ new 2004 model - IEEE 802.15.4 Radio -
Atmel Atmega128 16 MHz processor - 128kB
program memory - 4kB RAM - 512kB External
flash memory - 51-pin Expansion Connector
6
the HARDWARE MDA300
MDA300 new external sensor interface to
MicaZ - 8 Analog Inputs - 8 Digital I/O -
Internal Temperature Humidity Sensor -
Internal ADC - 64kB I2C EEPROM Can be used to
measure humidity, temperature, soil moisture,
light, wind speed and direction, motion,
rainfall, leaf wetness, pressure, and radiation.
7
The Software

• Industry standard is called TinyOS
• Developed at U.C. Berkeley. Written in nesC
• Support is everywhere
• But doesnt inherently support dynamic module
  loading (DML)
• We used SOS because Mike said so AND because
• It can do everything TinyOS can do with
  comparable efficiency DML its all in C
• Roy Shea (HMC 02) is one of its lead developers

8
What we did

• Downloaded, configured, and installed the SOS
  Kernel on our MicaZs and mastered the OS
• Implemented and set up a multi-hop network
• Sampled temperature readings from the
  refrigerator
• Developed the first ever drivers for the MDA300
  on the SOS platform
• an internal temperature and humidity sensor
• and an external thermistor temperature sensor

9
What we did CONTINUED

• Deployed a test network around the second floor
  of Sprague Library (see graph)
• Deployed a small network at the Benard Field
  Station (see graph)

10
SITE SCHEMATIC
11
DEPLOYMENT SITE
12
Deployment

• Location
• 20 feet from base station
• MicaZ radio not very good in bushy areas
• Power-saving turning off LEDs

Temperature at BFS from SHT15 (internal) sensor
over a 24 hour period.
13
Deployment

• Enclosures
• Sip-A-Cups transparent plastic bottles
• Straw hats yes, like Mikes straw hat

Temperature at BFS from external (thermistor)
sensor over a 24 hour period.
14
Results

• We achieved our goal we built and deployed our
  network. Mike was happy!
• But we experienced a number of problems. So
  LizardNet is not ready for full use yet.
• Top 3 problems
• We suspect SOS network tree routing algorithm
  needs some fine-tuning.
• MicaZ radio not very good when there is little
  line of sight between motes
• No acknowledgment system to deal with data loss

15
THE FUTURE

• Improve the SOS tree routing algorithm
• Use Mica2s for better radio performance
• Build acknowledgment system for data loss
• Improve power-saving techniques
• Add cameras

16
writing a driver the Process

• Pages and pages of FUN! (datasheets schematics)
• Tracing wires on design schematics
• Coding
• Debugging what we called blinking LEDs because
  we really didnt have better free debugging
  options.

17
writing a driver for the sht15
Step 1a Look for the SHT15 on the MDA300
schematic
18
writing a driver for the sht15
Step 1b Again on the MDA300, trace PW0 and INT3
to (in this case) the connector to the MicaZ.
19
writing a driver for the sht15
Step 2 On the MicaZ schematic, find the lines
that connect to lines 3 and 29 on the MDA300
connector and trace their names to the Atmel
Atmega128. Note In this case they happen to be
the same.
20
writing a driver for the sht15
Step 3 On the Atmel Atmega128 schematic, we
notice that INT3 is on line 9 and PW0 is on line
35. This means you will have to manipulate pins
PE7 and PC0 directly according to the SHT15
datasheet to read temperature and humidity data.
21
writing a driver for the sht15
Step 4 Get familiar with the processors API -
The Atmel Atmega128 uses whats called the AVR
Instruction Set - The AVR C libraries allow
direct access to all the pins on the
processor Step 5 Start coding away Step 6
Blink LEDs until you run out of battery power.
Then repeat steps 5 6.
22
ACKNOWLEDGMENTS
The LizardNet Team Alejandro Enriquez John
Hicks Kapambwe Kangombe James
Segedy Advisors Steven Adolf Mike
Erlinger Roy Shea (HMC 02)