DEC0905Remote Control of Home Appliances

ABSTRACT

The objective of this project is to enable users to remotely control home appliances and systems over the Internet using a web interface. The system will enable users access a web interface running on a server located at home. Users will be able to monitor the status of the home appliances, and issue control commands to perform specific functions. For Example open or close a garage door, program the home security system, reprogram the lawn watering system, etc. A function completion code is then returned to the user. The interface to home appliances will be through wireless Bluetooth communication. A microcontroller will be connected directly to the appliance being controlled and execute the commands. It will also interpret the feedback information and send it to the server.

Elie AbicharRachel Ayoroa

Bluetooth CommunicationThe Bluetooth USB adapter connected on the server side should be able to communicate to the micro-controller by sending and receiving data to the Bluetooth module that is connected on the UART (Universal Asynchronous Receiver / Transmitter) on the micro-controller board. For the purpose of Bluetooth communication, a specific protocol has been implemented to ensure the quality of data delivery and to provide a defined programming interface.

Bluetooth Protocol

Device Control Unit (DCU)Device control unit is the major component of this system. It consists of a microcontroller and a Bluetooth module. This unit will connect directly to the device and control the functioning of the device based on the commands received from the server. DCU connects to the server through Bluetooth using the Bluetooth module. DCU will communicate with the server in order to receive commands and send responses in order to provide status data to the user.SensorAn IR sensor is used to detect if the garage door is open or closed since the user might simply request the current status of the garage door.DevicesThis refers to the home appliance that is controlled by the DCU. Appliances considered for this project is a garage door opener. A relay circuit is used to connect the microcontroller to the garage door opener.

PROJECT DESCRIPTIONProblem StatementDesign and Implement a system that will enable users to remotely control their home appliances through the Internet and get feedback from the appliance.

Need StatementThe system designed will provide a new product to the newly emerging automation and controls market. It will be used in households to remotely control and monitor various home appliances through the Internet.

DESIGN REQUIREMENTS

SYSTEM OPERATING ENVIRONMENTThis system consists of several units that would operate both indoors and outdoors. Most of the system components will operate indoors under normal room temperature. The device control unit would operate both indoors and outdoors depending on the location of the device. The system would operate within the temperature and humidity limits for proper operation of hardware. A secure Internet connection would be necessary for the operation of the system.

SCHEDULE & RESOURCES

Chris TeferAnanta Upadhyaya

Faculty Advisor & ClientDr. Ahmed Kamal

FUNCTIONAL REQUIREMENTS

Access Point• Must Be Wireless• Must use a wireless

technology

Two-Way Communication Receiver• Must be able to send and receive messages

from the access point• Must communicate with the server wirelessly• Must interface directly to the Microcontroller

Microcontroller Units• Must be able to receive commands from the

access point.• Must be able to send status messages to the

server wirelessly through the access point.

• Must be able to control the device• Must be able to parse and interpret commands

Server Application• Must be accessible from the Internet• Must send commands through the access point

to the microcontroller

Client Interface• Must be able to receive user input• Must display the devices, and controls to those

devices, to the user• Must have a logon method for verifying users

NON FUNCTIONAL REQUIREMENTS

•Access point must have a footprint of less than 50 feet

• Wireless antennas must be internal or shorter than 4 inches

• GUI must have an intuitive look and feel for the user

User

ServerBluetooth

USB Adapter

Garage door

Opener

Bluetooth module

Microcontroller

Internet

SYSTEM BLOCK DIAGRAM

TESTINGServer TestingThe functionality of the server was first developed using a test program. This program allowed us to connect to the microcontroller via Bluetooth connection without using a fully developed web server.In later development of the server we also used a dialog box to let us know what actions were being performed on the server.

Microcontroller TestingSince the microcontroller communicates to three separate devices via UART, a test module that communicated through a computer’s serial port was developed using the UART library and a serial communication program called Bray’s Terminal.

Once the UART code was developed for basic serial communication, three separate test modules were developed for the infrared sensor, Bluetooth device, and garage door relay. Each module was developed to run on a separate port of the microcontroller.

An LCD screen connected to the microcontroller was used to output results for each test module until the Bluetooth server was fully functional.

Test Program

HTML GUI

Server Dialog

Bray’s Terminal

Easy Bluetooth Module $70LMX9820 $27Bluetooth USB Adapter $15IR Sensor $10Garage Door Opener Donated by Door & Fence StoreMicrocontroller Donated by Team May0613Poster $50Total $ 172

Resources

SYSTEM DESCRIPTION

Server DescriptionThe server contains several parts. The first of which is an HTTP servlet that runs server side. When this servlet is loaded it sends out a broadcast for all available Bluetooth devices. The devices are filtered for the Easy Bluetooth module, and the servlet gives the command that it is ready.

The second part of the server is the user interface. Once the servlet is ready, the user may go to the website which is running the servlet. The servlet passes back a list of devices found, and the user may select from a list of devices and start sending messages to the device. JavaScript is used to call an AJAX request to the servlet in order to pass off communications

Bluetooth Adapter Bluetooth Module Bluetooth Connection

n

Device name (**)

ab

*

b s

* *

Request for command

Send device name {gd,th} for garage door and thermostat respectively

Request a universal action

Acknowledgement

Request action * = {u,d} for opening or closing the garage door respectively

Acknowledgement (command executed)

Request the current status of the garage door. Status is detected by the IR sensor.

Respond the with status ** = {up,dn,op,cl} where

• up: garage door currently opening

• op: garage door already open

• dn: garage door currently closing

• cl: garage door already closed

Bluetooth Module

IR Sensor

Relay circuit

Work Breakdown by Hours

LCD Module