OUTDOORS WEATHER SENSOR

EEE212 – Group Project

Alexander Fandy George Fearnall Gareth Walley Brian Jonathan Reza Safari

Wireless Sensors in Homes

Many Possibilities ¨  Air Conditioner ¨  Water Heater ¨  Curtain Control ¨  Lights ¨  CCTV

Wireless Sensors in Outdoors ¨  Localized weather conditions ¨  Easy transition from Nursery/Greenhouse to garden ¨  Ideal location and conditions for specific plants ¨  Saving plants from dying by providing perfect living

conditions ¨  Smart measurement of environmental data

Green house Bright Location

Veg. Patch

Shaded Location

Implementation ¨  In this project, 2 X-Bee radios were implemented. ¨  One radio as an end device communicating with the sensors and the

other at the computer side receiving data and passing them to MATLAB.

¨  Because of the large number of I/O pins, the Xbee on the sensors simplified design and implementation no longer requiring Arduino on the base.

¨  Data passed from base to the computer could be intercepted by Arduino, however it is much simpler for data to be passed to MATLAB for visual representation.

Implementation Details ¨  X-CTU configured X-Bee

radios with firmware to operate in the designated role.

¨  Configuration of radio address.

¨  Allows continued communication

Xbee Wireless Radio and Zigbee ¨  Small wireless communication module ¨  Low power consumption ¨  Mesh network compatibility ¨  250 kBits/s, 2.4 GHz based

on IEEE standard 802.15.4

Advantages and Disadvantages ¨  Minimum power consumption

suitable for wireless nodes ¨  Small, lightweight ¨  10 I/O pins ¨  Digital and analogue input ¨  Each radio can be set as the

controller or the endpoint node

¨  Sleep mode (reduced power consumption)

¨  Not the best choice for large data

¨  Minimum logic capability

MATLAB Interface ¨  Matlab has a serial package ¨  Allows reading writing to the serial port ¨  Analysing packets of data, it is possible to decode

the digital output of the Xbee

Data Collection ¨  A standalone Matlab program runs in the

background. ¨  Every X minutes it collects data from each sensor. ¨  From this it saves data to a database which can be

accessed from Matlab

Data Visualization ¨  Matlab has GUI programming capabilities. ¨  Using these, it is possible to create a standalone

program which can be run on a machine without Matlab.

¨  The controls call data from the database then plot them automatically.

¨  People inexperienced with Matlab would have no problem using this software.

Circuit Topology

Sensors

Xbee Router

Xbee Coordinator

Computer

Sensors and Battery ¨  Rain Sensor ¨  Temperature and Humidity ¨  Light Sensor ¨  Power supply- Li-ion Battery most common and

effective rechargeable battery 3.6V

Implementation Difficulties ¨  Xbee firmware ¨  Coding compatability ¨  Digital I/O

Possible Upgrades ¨  Solar Charging ¨  Mesh Network ¨  Internet integration ¨  More sensors ¨  Phone application ¨  Multiple data collection nodes – mesh network ¨  Greater graphing capabilities – heat maps ¨  Add functionality for live data to be viewed