Design And Construction Of A Microcontroller Based RF Remote Control For Home Electrical Appliances

ABSTRACT

This work presented here is to controlled independent home electrical appliances through RF based remote system. From any place without any line of sight around the house, RF based wireless remote control system can change the state of the electrical appliances either in on state or off state. The controlling circuit is built around RF transmitter and RF Receiver modules which are operating at 434 MHz along with encoder IC HT12E and decoder IC HT12D with few passive components. The four different channels at the encoder are used as input switches and the four channels at the decoder output are connected to the appliances through a relay. Here the transmission technique is amplitude shift keying (ASK) and the circuit is powered with 9 V. The main objective of this work is to build the circuit that controls appliances and to make it work without line of sight requirement using the RF technology.

TABLE OF CONTENTS

COVER PAGE

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWELDGEMENT

ABSTRACT

CHAPTER ONE

INTRODUCTION

1.1      BACKGROUND OF THE PROJECT

• OBJECTIVE OF THE PROJECT
• PURPOSE OF THE PROJECT
• LIMITATION OF THE PROJECT
• SIGNIFICANCE OF THE PROJECT
• SCOPE OF THE PROJECT
• PROBLEM OF THE PROJECT
• APPLICATION OF THE PROJECT
• PROJECT ORGANISATION

CHAPTER TWO

LITERATURE REVIEW

• OVERVIEW OF THE PROJECT
• HISTORICAL BACKGROUND OF THE PROJECT
• REMOTE CONTROL TECHNOLOGY
• OVERVIEW OF INFRARED MODULE
• TYPES OF RF MODULES

CHAPTER THREE

SYSTEM DESIGN

• SYSTEM BUILDING BLOCK
• SYSTEM WORKING PRINCIPLE
• SYSTEM CIRCUIT DIAGRAM AND COMPONENETS
• SYSTEM OPERATION
• HOW TO DESIGN RF BASED HOME AUTOMATION CIRCUIT
• RF MODULE (RF TRANSMITTER AND RECEIVER) DESCRIPTION

CHAPTER FOUR

TESTING AND RESULTS

• CONSTRUCTION PROCEDURE AND TESTING
• INSTALLATION OF THE COMPLET DESIGN
• ASSEMBLING OF SECTIONS
• TESTING OF SYSTEM OPERATION
• INSTALLATION OF THE COMPLETED DESIGN
• SYSTEM RECEIVER AND TRANSMITTER DESIGNED BOARD
• HOW TO OPERATE SYSTEM
• RF REMOTE CONTROL CIRCUIT ADVANTAGES
• RF REMOTE CONTROL CIRCUIT APPLICATIONS

CHAPTER FIVE

• CONCLUSION
• REFERENCES

CHAPTER ONE

1.1                                                        INTRODUCTION

With the advancement of technology, number of equipments and modern household appliances increases to make life easier and comfort. Operating them manually is a tedious job and again hectic sometimes. If one can control devices like TV, fan, light or a music system with a remote from a distance place just by pressing the button, life will become simpler. Home automation is becoming very common these days as technology advances to reduce manual work. To switch on or off the devices one has to move to the switch board which is inconvenient even for an able person. If all this manual work is replaced by a single remote control even the aged and disable person can do the task like a normal person. Much related work has been reported for the same function by different groups with different approaches. Multiple home devices switch can be control with a designed system using microcontroller as heart of the circuit with android based mobile phone. Here the mode of controlling devices is by sending command wirelessly through Bluetooth [1]. IR remote control has a very wide application in the field of electronics. IR based remote control for controlling multiple home appliances with microcontroller is also reported for the same function [2], [3]. Another approach is by GSM based for home automation. Here it has a wider coverage area. So to control any house hold appliances from a distance place within the network area coverage sending a short sms code will either ON or OFF the devices at home [4], [5]. All these work is carried out for the same function in a different way by using different technology. Some use Bluetooth technology other use GSM technology or IR technology. Each technology has its own advantages and disadvantages over the other but they all serve the common purpose to replace manual work. The main objective of this work is to create another system to control multiple appliances by using RF technology. One of the main advantages of RF based remote control is that it can operate the appliances without the requirement of line of sight within its specified range efficiently. Figure.1 shows the basic overall design system to control four independent home appliances like TV, music system, room light and fan through a remote with four switches.

1.1                                                   AIM OF THE PROJECT

The main aim of this work is to control home appliances fan, television, air conditioner, lamps using RF technology. This device has been designed around the 8051 SERIES microcontroller

1.2                                             OBJECTIVE OF THE PROJECT

The main objectives of our proposed project are (i) To sense the existing status of the remote devices and obtain information in the display, (ii) To control the remotely operated devices using control signals, (iii) To take corrective action automatically as per requirement, and (iv)To protect the equipments from unwanted operations.
1.3                                                      SCOPE OF THE PROJECT

This device allows for a user to remotely control and monitor multiple home appliances using a RF signal. This system will be a powerful and flexible tool that will offer this service at any time, and from anywhere with the constraints of the technologies being applied. Possible target appliances include (but are not limited to) climate control systems, security systems, and lights; anything with an electrical interface.

The proposed approach for designing this system is to implement a microcontroller-based control module that receives its instructions and commands from an RF transmitter and receiver. The microcontroller then will carry out the issued commands and then communicate the status of a given appliance or device back to the receiver.

1.4                                            OPERATING ENVIRONMENT

The control system will include two separate units: the transmitter, and the receiver unit. There will therefore be two operating environments. The transmitter will operate indoors and outdoors whereas the receiver unit will operate indoors within the temperature and humidity limits for proper operation of the hardware.

1.5                                          LIMITATIONS OF THE PROJECT

The following is a list of limitations for the project.

·        The receiver must reside in a location where a signal with sufficient strength can be received.

·        Only devices with electrical controlling input ports will be possible targets for control.

·        The receiver must have a power source (220vac) attached at all times.

·        Operation of the controlling unit is only possible through rf signal

1.6                                           LIMITATION OF THE PROJECT

The following is a list of problems and assumptions for the project;

·        The user and control unit will establish communication via rf signal.

·        The controlled appliances will have to have an electrical interface in order to be controlled by microcontroller.

• The RF Transmitter, Receiver and the microcontroller unit must be separately powered for better operation.
• It has limited life time due to use of battery for powering the circuit.

1.9                                                  PROBLEM STATEMENT

The only problem notice on this work is the antenna problem:

1. wrong position of the antenna can affect the signal
2. Over or under length of the antenna can also determine the operating strength of the device.

• The strength of the battery can also affect the operation of the system

1.8                                         APPLICATIONS OF THE PROJECT

This project can be used in Industries, This system can be employed in houses, where people often forget to switch off electrical appliances. This system can be used to control AC’s to set the room temperature when we are outside. We can extend this circuit to control many electrical devices with some modifications using 4 x16 decoder IC. This work is aimed toward average consumers who wish to control household appliances remotely from their cell phones provided that the appliances are electrically controllable.  Example of feasible appliances and applications under consideration include; enable/disable security systems, fans, lights, kitchen appliances, and adjusting the temperatures settings of a heating/ventilation/air conditioning system.

This system can be used in industrial applications. This system can be employed in houses, where people often forget to switch off electrical appliances.

1.8                                         SIGNIFICANCE OF THE PROJECT

Home Appliance Control using radio frequency can be used to turn ON / OFF the devices and various appliances in our home. It can prove very useful for disabled people. This project can also be used in shop, offices, industry. User has to dial a call to the mobile which is connected to the project. Then user has to press various keys to control the devices. In this work:

• Quick response is achieved.
• Construction is easy.
• Easy to maintain and repair.
• Comparatively the operation cost is less.
• Design is efficient and low cost.
• Power consumption is low.
• Controlling electrical devices wirelessly
• Saves electricity (when we forget to switch off and go out).
• We can control appliances from any place round the globe.
• No coding is required.
• This circuit can be used to wirelessly control different home appliances.
• As it is an RF Communication based system, there is no need for any line of sight communication as in case of IR Communication.
• The RF Transmitter and RF Receiver can work up to 100 meters even when there is an obstruction between them.

1.7                                        PROJECT WORK ORGANISATION

The various stages involved in the development of this project have been properly put into five chapters to enhance comprehensive and concise reading. In this project thesis, the project is organized sequentially as follows:

Chapter one of this work is on the introduction to this study. In this chapter, the background, significance, objective limitation and problem of this study were discussed.

Chapter two is on literature review of this study. In this chapter, all the literature pertaining to this work was reviewed.

Chapter three is on design methodology. In this chapter all the method involved during the design and construction were discussed.

Chapter four is on testing analysis. All testing that result accurate functionality was analyzed.

Chapter five is on conclusion, recommendation and references.