i

SMS BASED REMOTE CONTROLLING OF

HOME APPLIANCES

A Seminar Report

Submitted by

Phuntsho Gayenden

ECE2009064

Electronics and Communication Engineering

College of Science and Technology

Rinchending :: Phuentsholing

May 2012

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ABSTRACT

Today technology has allowed us to do many things which we thought were

impossible in early day. Out of all, wireless technology has been one of the most

significant inventions in human history. Not only can we exchange information

but we can also control devices wirelessly. This paper is about the wireless

control of home appliances. The first half of the paper is about the study of

required components while the second half is about the implementation of the

combined components to achieve remote controlling.

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ACKNOWLEMENT

My genuine thanks go to Mr.Tashi who has been the guide for this particular

Technical Seminar topic. I would also like to extend my deepest thanks to the

College library and IT department for facilitating with resources required to

complete this seminar. I’d also like to thank Mr.Gopal Chandra Nepal and

Mr.Rajen Biswa for their recommendations on improvement of the simulation.

I’d also like to extend my thanks to the creators of NetBeans IDE powered by

java and Oracle for their wonderful creation of a power platform where my

simulations are done.

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TABLE OF CONTENTS

Abstract ..................................................................................................................................... ii

Acknowlement ..........................................................................................................................iii

Table of Contents ..................................................................................................................... iv

List of Figures .......................................................................................................................... vi

List of Tables ........................................................................................................................... vii

List of Abbreviations .............................................................................................................viii

1 Introduction ...................................................................................................................... 1

2 Literature Review ............................................................................................................. 2

2.1 Introduction .................................................................................................................. 2

2.2 Home Appliance Control Systems ............................................................................... 2

2.2.1 Appliance Control................................................................................................. 3

2.2.2 Security ................................................................................................................. 3

2.2.3 Benefits ................................................................................................................. 4

2.3 Short Message Service ................................................................................................. 4

2.3.1 About Short Message Service............................................................................... 4

2.3.2 GSM Modem ........................................................................................................ 5

2.3.3 Testing the GSM Modem ..................................................................................... 6

2.4 Summary ...................................................................................................................... 6

3 Simulation.......................................................................................................................... 7

3.1 Introduction .................................................................................................................. 7

3.2 Simulation Set-up......................................................................................................... 7

3.3 Simulation Results and Analysis ................................................................................. 9

3.3.1 Using SMS to Turn On/Off Appliances ............................................................... 9

3.3.2 Toggling Appliance Directly for HACS ............................................................. 10

3.3.3 Breach Alert ........................................................................................................ 11

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4 Critical Evaluation and Analysis................................................................................... 12

5 Feasibility of HACS in Bhutan ...................................................................................... 13

6 Conclusion ....................................................................................................................... 14

References ................................................................................................................................ 15

Appendix - 1 ............................................................................................................................ 16

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LIST OF FIGURES

Figure 2.1: Simple HACS conceptual block diagram. ............................................................... 2

Figure 2.2: Sequence diagram for the control of a Garage door. ............................................... 3

Figure 2.3: Sequence diagram for security in HACS. ................................................................ 3

Figure 2.4: GSM Modem............................................................................................................ 5

Figure 3.1: Block diagram of new modified HACS equipped with GSM Modem .................... 7

Figure 3.2: Overview of the simulation ...................................................................................... 8

Figure 3.3: Using SMS to turn on/off appliance ........................................................................ 9

Figure 3.4: Turning off the appliance using SMS ...................................................................... 9

Figure 3.5: Appliance turned on and off after authentication. .................................................. 10

Figure 3.6: Breach by unknown user ........................................................................................ 10

Figure 3.7: Breach example alert .............................................................................................. 11

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LIST OF TABLES

Table 2.1: Step illustration of the working of a SMS message. ................................................. 4

Table 2.2: List of some common AT commands for GSM Modem ........................................... 5

viii

LIST OF ABBREVIATIONS

Sl. No. Terms Descriptions

1 CST College of Science and Technology

2 GSM Global System for Mobile communication

3 HACS Home Appliance Control System

4 HLR Home Location Register

5 IDE Integrated Development Environment

6 IEEE Institute of Electrical and Electronics Engineers

7 MSC Mobile Switching Center

8 SMS Short Message Service

9 SMSC Short Message Service Center

10 VLR Visitor Location Register

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1 INTRODUCTION

The modern technology has enabled us to make our life easier with the invention of many

high-tech devices and equipment. The most common ones are the ones which we use at home.

For example, television, air conditioner, lights, etc. are commonly used by everyone.

Further with the advancement of technology, a concept of smart home has come into play

where a home is equipped with special facilities for the occupants to control an array of

automated devices. But the occupants cannot confine themselves at home all the time. A

smart home can even be smarter if the controls can be done even away from home. For

example, it would be so wonderful if one could turn on the heater and the microwave oven on

a cold winter night while returning home from elsewhere.

Mobile phone has become a necessity in the 21st century. Everyone has their own brand of

phone and carry it with them all the time, and even when travelling. Holding the power to

control home appliances using a phone will bring a whole new age of smart control. It means

that one has the control of the home appliances from almost anywhere away from home.

The appliances can interact equally by responding its status through the SMS. With that even

security measures can be taken. Any breach in the property can be sensed and reported to the

owner’s cell phone.

A paper published in 2009 by Dr. Malik S.H.Khiyal with Aihab Khan and Erum Shehzadi

from Fatima Jinnah Women University in Informing Science and Information Technology

clearly states the effective use of SMS for Automating appliances and security. However their

stress mainly lies in security while the extensive controls have been compromised with the

promise of future work release with the hardware [1].

Duk-Jin Kim, Jeff Dix, Jyotsna Kotur, Warren Pena, Yajing Zhao and Yasaman Haghpanah

on Home Appliance Control System (released: October 12th, 2006) has an extensive view of

controls over the appliances. The controls were so detailed that even setting up the microwave

oven’s time for cooking through the controls were possible [2]. The remote controlling of the

controls was not discussed.

This presents SMS based HACS and its applications. Rest of the paper is organised as

follows. Section 2 addresses the literature review. Section 3 discusses the simulation and

analysis. Section 4 presents the critical analysis. Section 5 addresses the feasibility of the

HACS in Bhutan. Finally, section 6 draws the conclusion.

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2 LITERATURE REVIEW

2.1 Introduction

For the implementation of SMS based control of home appliance, we need to understand SMS

and HACS concepts. The goal to achieve is the combined application of SMS and HACS.

This would mean that knowing the components separately is crucial as well.

2.2 Home Appliance Control Systems

We have had evolutions of devices right from the early stage of their development [2].

Before, televisions used to come with attached controls with not much option. Now we get a

remote control to control it wirelessly with options capable enough to correct the pictures

displayed.

In a similar way, evolution has also touched our way of interacting with home appliances.

Home Appliance Control System (HACS) is one of the products of this evolution. It provides

a way to access control over home appliance from a single place and be able to coordinate

them [2]. In addition to that the status of the appliances can also be known.

Figure 2.1 shows a simple HACS block diagram. The computer in the shaded box holds all

the authority of the entire system and acts as the server for the user controls. It has the control

and security information of the system. The lines in the figure indicate channel through which

the devices communicate with each other. Usually the channel between the main computer

and the appliances are wired medium.

Figure 2.1: Simple HACS conceptual block diagram.

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2.2.1 Appliance Control

With the implementation of security, HACS is safe. The second task is to control the home

appliance. Figure 2.2 illustrates how this can be achieved. After the authentication of the user,

the user is allowed to interact with the HACS for appliance control [6]. The options can vary

according the HACS software used or the configuration. In the sequence diagram above, the

user is provided with the facility to view the list of applications and commands available.

Figure 2.2: Sequence diagram for the control of a Garage door.

2.2.2 Security

Security always comes into play when it comes to control system. HACS need to be able to

reject the control commands should unauthenticated person might try to tamper the system.

For that purpose, it’s a must that HACS should be able to recognize the user. This is achieved

by setting a username and password for a particular user’s usage. Figure 2.3 shows how the

username and password is implemented. A user will be given three tries. If the three tries fails

then the HACS will be locked therefore avoiding the breach [3].

Figure 2.3: Sequence diagram for security in HACS.

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2.2.3 Benefits

Having HACS at home can make life much easier. It can provide us with better security and

maintenance of the appliances [1][6]. It can also save a lot of time because the user need not

be physically present to set the work done.

It can also provide a better safety. For example, if there is a fire in the house, HACS will be

able to detect it and contact the fire department.

2.3 Short Message Service

2.3.1 About Short Message Service

Short Message Service (SMS) is a method of communication that sends text between cell

phones, or from a PC or handheld to a cell phone. The "short" part refers to the maximum size

of the text messages: 160 characters (letters, numbers or symbols in the Latin alphabet). For

other alphabets, such as Chinese, the maximum SMS size is 70 characters [9].

SMS is provided by the GSM network provider by default today. The exchange can be done

from phone to phone or computer to phone. For the exchange of SMS between a computer

and a phone, a GSM modem is required which is discussed in the following section.

The pathway of the SMS on its journey to the destination can be illustrated with steps which

are shown in Table 2.1.

Table 2.1: Step illustration of the working of a SMS message [9].

Step 1: The SMS message is submitted to the service provider's SMS center (SMSC).

Step 2: The SMSC sends a request to the Home Location Register (HLR) and receives the routing information for the recipient.

Step 3: The message is forwarded to Mobile Switching Center (MSC).

Step 4: MSC collects recipients’ information from Visitor Location Register (VLR).

Step 5: MSC forwards the message to a Mobile Server.

Step 6: MSC returns the outcome of the operation to SMSC.

Step 7: SMSC reports the delivery status to the sender.

The sender of the message can be a cell phone or a computer or any capable device. In order

to use the service from a computer, one will need a GSM Modem which is discussed on the

following section.

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2.3.2 GSM Modem

A GSM modem (hardware component) will allow the capability to send and receive SMS to

and from the system from which the control signals will be derived. A typical GSM modem is

shown in Figure 4.1. It requires a sim card and a network provider for operation and works

just like mobile phone. These modems are more frequently connected to computers which

allow the computers to communicate with the mobile network [8]. They are most probably

used for sending/receiving SMS. The communication with the computer usually happens in

the serial port RS232 [7].

Figure 2.4: GSM Modem

Unlike mobile phones, a GSM modem doesn’t have a keypad and display to interact with. It

just accepts certain commands through a serial interface and acknowledges for those. These

commands are called as AT commands. AT stands for attention. The methods of retrieving

control signal from the GSM are shown in Table 2.2 [7].

Table 2.2: List of some common AT commands for GSM Modem

AT Commands Meaning

AT+CSCA="num" Set message centre number to "num"

AT+CGMI Get the name of manufacturer

AT+GMI Get the ID of manufacturer

AT+GMM Get the Model Information

AT+CPAS Get mobile phone activity status

AT+CSQ Get radio signal strength

AT+CMGS, AT+CMSS Send SMS messages

AT+CMGR, AT+CMGL Read SMS messages

AT+CMGD Delete SMS messages

AT+CMGF Operate in text mode

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2.3.3 Testing the GSM Modem

The GSM modem can be tested by connecting it with a PC. The modem is equipped

with a RS232 cable. A Serial to USB converter can be used to connect with the PC.

Serial parameters are to be configured to 8N1 and the baud rate is set to 9600bps.

Commands can be sent to the modem using any serial communication program like

HyperTerminal, Minicom etc.

Sending the command "AT" to the modem will send back a result code "OK" which

states that the modem is responding. If it’s not working, it will send "ERROR".

2.4 Summary

HACS provide the controlling of the home appliance while SMS allows the communication

path for long distance. Upon its combination, we can achieve the remote controlling of

HACS. The following Section 2 is about the combined technology of HACS and SMS. It is

then simulated in a computer and shown under the same section.

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3 SIMULATION

3.1 Introduction

With HACS software ready, a computer can now be equipped with GSM Modem so that it

can receive and send SMS through GSM network. Figure 3.1 shows the HACS system in

combination with the GSM hardware. Now the user can send SMS and communicate with the

computer with HACS installed.

Figure 3.1: Block diagram of new modified HACS equipped with GSM Modem [1]

The first mode of communication takes place between the modem and the Mobile Device in

Radio Frequency. The SMS is then transferred from the GSM modem to the computer

through the port RS232 [1]. The computer then can analyze the received SMS, decode it and

implement the command after the security check.

The current simulation is based to show the connection of SMS messages to the control

commands in HACS.

3.2 Simulation Set-up

The simulation is set-up in the NetBeans IDE 6.9.1 (Build 201007282301) using 1.6.0_06;

Java HotSpot(TM) Client VM 10.0-b22 in the Windows Vista version 6.1 running on x86;

Cp1252; en_US (nb).

The NetBeans IDE is a free, open-source Integrated Development Environment for software

developers. All the tools needed to create professional desktop, enterprise, web and mobile

applications, in Java, C/C++ and a variety of dynamic languages are available. The Integrated

Development Environment (IDE) runs on many platforms including Windows, Linux, Solaris,

and Mac OS [10].

Over view of the program (simulation) is shown in Figure 3.2. Since the program is custom

made, there are further details to be remembered, which are as follows:

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The textbox on the top left of the figure is used to simulate SMS service.

The textbox right below is made to give the usage hints for the user.

Applications are listed below the “Task” label. They can be toggled on and off just by

clicking in the boxes if the program is logged in with valid username and password.

If the program is not logged in, then only SMS simulation will work.

The breach buttons are used to simulate breaches and will work even if the program is

not logged in.

The syntax of the SMS for command purposes is: <password> <Application>

<command>

Username is taken as the phone number while the password has to be set.

Application tab can be replaced by “TV”, ”Lights”, ”Stereo”, ”Radio”, ”Fan”,

”Boiler”, “AC”, “Ventilation”, and “Heater”.

Command tab can either contain “on” or “off”.

The commands are made case in-sensitive for convenience.

Figure 3.2: Overview of the simulation

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3.3 Simulation Results and Analysis

3.3.1 Using SMS to Turn On/Off Appliances

The password set for the program is 123. Upon simulating the SMS with content “123 AC

on”, the AC was turned on.

The syntax of the command used on the “User’s phone screen” where SMS is being simulated

is <password> <Appliance> <status>. After tying “123 AC on”, the output as on Figure 3.3,

AC was turned on. The circled area shows which part of the program is taking the active part.

Figure 3.3: Using SMS to turn on/off appliance

In a similar way, to turn off the AC, we can simulate the SMS with the content “123 Ac off”.

In this manner, SMS can be used to toggle the controls of the available appliances with

HACS.

Figure 3.4: Turning off the appliance using SMS

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3.3.2 Toggling Appliance Directly for HACS

The username set is “+97517746477” and password is “123”. If we log in with this

information, we can toggle the appliance directly from the program.

Figure 3.5 shows the toggling of home appliance status after logged in with the username and

password. This option is used in order to take control over the home appliance directly from

the control system. The user cannot control the appliances even from the mail control system

unless verification of the user is given.

Figure 3.5: Appliance turned on and off after authentication.

If the username do not match, a breach message will be sent if the unknown user presses the

login button to the home owner thereby alerting about security breach attempt. This can also

help to identify the person trying to hack over the control system.

Figure 3.6: Breach by unknown user

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3.3.3 Breach Alert

If any security alert is detected, the HACS can send SMS to the user about the issue.

Figure 3.7 shows an alert to the user’s phone screen when a breach to the gate was made by

clicking the circled button on the right.

Figure 3.7: Breach example alert

Several sensors can be installed to detect breaches in different places. If sensors are placed on

every window available, then running around to check if they are closed will be un-necessary.

The sensors can be used to trigger cameras if available to capture the breach events.

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4 CRITICAL EVALUATION AND ANALYSIS

The simulation shows how easy it is to implement the system practically. It is functional in its

security as well as in controls. The program illustrated above is just a simple program

controlling many appliances at once. The program can be easily modified to make a sub

program specific to only one appliance but with many controls.

The main strength of SMS based remote controlling of home appliances is that the system is

location independent [4]. This creates much room for user’s ease with availability of control

over distance. GSM technology has the benefit of being available even in remote areas.

The alert mechanism for any breach in the property also is a strong advantage for the use of

the system. The system also uses low cost components which are easily available in the

market. The whole system is simple and can be changed allowing/disabling certain features

easily [4].

One of the constraints of this system is that it is very vulnerable to power failure thus can be

interrupted if the source goes down. Setting up the appliances with the HACS can be a time

taking job.

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5 FEASIBILITY OF HACS IN BHUTAN

Not so long ago, Bhutan was still young and had very little technological facilities in hand.

But now, within a short period of time, Bhutan is steadily observing the growth of technology

dependence among the people. The use of mobile phone users are also increasing day by day.

The number of appliances that we use today has also increased significantly. With increasing

amount of appliances, controlling over every individual appliance manually would consume

time. The concept of smart home will not take much time to break out in Bhutan.

Bhutan has not yet seen a smart Home with facility such as HACS system even though

several softwares are available in the market for HACS system today. X10 Active Home

Controller Pro [5] for example comes as a package with its own hardware and software

module. The price range with the set of different packages is from US $10 to $300.

All the resources are available readily in the market and one just need to purchase the

necessary items which would not cost much.

Therefore, installing SMS based remote controlling of home appliances is not quite hard to

achieve in Bhutan. As seen in the simulation, the concept is very simple and is very cheap to

imply. It also is very beneficial.

Assuming that one already owns a computer and a cell phone, the only expenditure that goes

for is on GSM Modem and a stable HACS software and hardware from the market. Another

alternative for GSM Modem is to use the phone itself. However the phone needs to support

that specific utility and to use a phone for just this application sounds unwise. Having an SMS

controlled home appliance system installed will not only make life easier for the users but

also provide them with better security options.

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6 CONCLUSION

In earlier days we used to have stiff buttons for controls. It evolved to the soft buttons and

now touch sensors are used instead. Similarly, pressure cooker for rice evolved to automated

electrical rice cooker.

Everywhere we look, the technology is pushing the devices to evolve into much better than

their previous ones. Remote controlling of home appliances is yet another evolution of its

earlier controlling of only one device remotely. Not only is it cheap to implement but also has

several advantages over security and control for the user.

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REFERENCES

[1] M. S. H. Khiyal, A. Khan and E. Shehzadi, “SMS Based Wireless Home Appliance

Control System for Automating Appliances and Security,” Rawalpindi, 2009.

[2] A. R. Delgado, R. Picking and V. Grout, “Remote-Controlled Home Automation

Systems with Different Network Technologies,” Wrexham, 2006.

[3] D. J. Kim, J. Dix, J. Kotur, W. Pena, Y. Zhao and Y. Haghpanah, “Home Appliance

Control System,” 2006.

[4] K. Patel, A. Immaneni, S. Kapoor, M. Atluri and A. Muthuveeraganapathy, “Home

Appliance Control System Presentation,” 2006.

[5] R. Shahriyar, E. Hoque, S. M. Sohan, I. Naim, M. M. Akbar and M. K. Khan,

“Remote Controlling of Home Appliances using Mobile Telephony,” International

Journal of Smart Home, vol. 3, no. 3, pp. 39-46, July 2008.

[6] K. Filsoof, P. Reddy, Y. Hakki, K. Thompson and M. Kubanski, “Smart Hourse

with Power Line Communication Network,” in IEEE, 2010.

[7] “3GPP TS 27.007 Specification and riles,” Telit Wireless solutions, 2012.

[8] J. Hord, “How Stuff Works,” 2005. [Online]. Available:

http://iris.nyit.edu/~kkhoo/Spring2009/MIST760/HowStuffWorks/HowStuffWorks-

-SMS.pdf. [Accessed 28 April 2012].

[9] M. Harrington, “Mobile Device Forensics,” 22 February 2007. [Online]. Available:

http://mobileforensics.wordpress.com/2007/02/22/how-sms-works/. [Accessed 28

April 2012].

[10] Oracle, Java, MySQL, OpenOffice.org, java.net, Hudson, JavaFx, OpenJDK,

“NetBeans,” Oracle Corporation, 2012. [Online]. Available:

http://netbeans.org/features/all.html. [Accessed 7 May 2012].

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APPENDIX - 1

Appliance turned on and off after authentication. p.10

Block diagram of new modified HACS equipped with GSM Modem p.7

Breach by unknown user p.10

Breach example alert p.11

GSM Modem p.5

List of some common AT commands for GSM Modem p.5

Overview of the simulation p.8

Sequence diagram for security in HACS p.3

Sequence diagram for the control of a Garage door. p.3

Simple HACS conceptual block diagram p.2

Step illustration of the working of a SMS message p.4

Turning off the appliance using SMS p.9

Using SMS to turn on/off appliance p.9