PERVASIVE HOME AUTOMATION THROUGH MOBILE PHONES

Transcription

1 International Journal of ISSN Systems and Technologies IJST Vol.4, No.1, pp KLEF 2010 PERVASIVE HOME AUTOMATION THROUGH MOBILE PHONES R. Ganesan, S. Leoprabu TIFAC-CORE in Pervasive Computing Technologies, Velammal Engineering College, Chennai 66. Abstract; One of the main aims of the Pervasive System is to be able to adapt themselves in execution time to the changes in the number of resources available, the mobility of the users, variability in the needs of the users and failures of the system. The system is developed to Home automation process through spoken commands using mobile. A text message is generated and sent to control system mobile in form of SMS. On receipt of SMS, control system mobile informs Micro-controller based card, which performs specified task and interfaced with the hardware. This system will be very beneficial to Control from anywhere in world if cellular coverage is available and to the disabled as controlling a home appliance would be just a command away. Keyword: Pervasive Computing, Home Automation Process, GSM, Speech to text conversion 1.INTRODUCTION Latest mobiles can not only allow you to click pictures, play music, store your address book, hook you to Internet, download s, guide you through maze of city streets but also enable you to watch latest blockbusters, favorite TV programs, book tickets and transact business. As a result, large section of population is continuously upgrading their mobile models to avail these exquisite features. The dumped older models having just voice call and messaging facility are available at throwaway prices. There are many systems which have already implemented home automation, but they lack certain beneficial aspects in their system. First, the communication cost. Second, the complex wiring of the system. Third, the usage of a PC to control the HACS (home automation control system). This paper proposes a design thought which, one can control home appliances. Communication is carried out through GSM technology. A system is developed for remote monitoring and control of devices using mobile through spoken commands. 43

2 R.Ganesan The system offer several attractive features like control from anywhere in world if cellular coverage is available acknowledgement about execution of command from system to user uses spoken commands from user for control ease of implementation and cost-effective approach Figure 1 shows the architecture diagram of our system. The system comprises of three main parts. (1) The user end (2) The processing part and (3) The interface circuit. FIGURE 1: System Architecture In this the User command given through speech and it is converted into speech to text message. The system creates application software installed in the mobile phones. Mode of communication- text messages SMS sent to GSM modem and Use of relay controllers Command activates respective appliances. 1. LITERATURE SURVEY A number of Systems are available for home automation, and a number of attempts have been made to develop, implement and maintain some degree of standardization for the control System of home automation. It cannot meet the requirements of home/office appliances [1]. Control of home appliances remotely when the user is away from the place. The system is SMS based and uses wireless technology [2]. To implement real-time surveillance of the home security, the intelligent remote monitoring system was developed 44

3 Pervasive Home for home security based on ZigBee technology and GSM / GPRS network [3]. SMS control technique based on the instant messenger [4]. To develop technologies for the users to input their requests by familiar way and clarify what they want to know with displaying the retrieved information with suitable method [5]. Segmental conditional random field framework for large vocabulary continuous speech recognition [6]. The home appliances are controlled by the home server, which operates according to the user commands received from the mobile phone via the cellular modem. Extend the capability of mobile phone for remote monitoring and control of devices 2. PROPOSED SYSTEM DESIGN Our home automation system uses a mobile to recognize speech using a high level language code (J2ME) and it then automatically converts it into a text format. The message received by the GSM modem will thus control the respective domestic appliance. Our home automation system is a complex integration of many components put together. The GUI interface for the mobile phone is devised so that the user can interact with this application in an easy way. First, the user starts the application and gives the command. The command is converted to a text format and the text message is sent to the GSM modem, set up in the home/office through the MSP (Mobile Service Provider). FIGURE 2: Control Flow Diagram 2.1 FEATURES OF THE PROPOSED SYSTEM Our system uses voice-text messages as the major mode of communication, thus making the system a wireless network, at large. This feature of our system facilitates ubiquitous access to the appliances from anywhere across the globe. Inflation has always been a major crisis and it has largely affected the area of mobile communication too. With the rapid growth in 45

4 R.Ganesan technology, hand-held devices are most common nowadays, be it a laptop or a wearable computer or a mobile phone! Our system uses only a mobile phone for remote access. It does not require the use of a personal computer (PC), thus making the system less cumbersome. Our system does not rely on the Internet. This acts as an added advantage to our system as the Internet service is not reliable always due to power failures. Error rate and delays are minimal, as there is no ambiguity in the format of the voice text message sent. It is a real-time system, which is very simple to use such that even a layman can use this application and this aims at providing a global solution to ease the daily activities for the physically challenged. 3. MODULE DESCRIPTION The system architecture comprises of many modules. They are: (i) speech recognition, speech to text conversion and SMS generation (ii) designing the GUI for mobile phone (iii) circuit design for the GSM modem (iv) firm ware design (v) circuit design for control of domestic home appliances. 3.1 Speech recognition, speech to text conversion and SMS generation The home automation system uses a small grammar large user group speech recognition algorithm. Hence, the system need not be configured for every new user using the system. This eliminates the need for a training module, thus making the working of the system viable to many users. The word hardly used by the system would cover the names of all devices and the basic operations they perform. The speech recognition can first be simulated using a PC, so that it recognizes our voice and produces an equivalent text, with the help of J2ME (Java 2 Micro Edition). The process of speech recognition can be divided into three parts (see Fig. 3): feature extraction, feature classification and word rejection. Feature extraction is preceded by filtering and digital sampling of the acoustic signal. Feature classification phase, extracted features are matched with memorized features representing phonemes, groups of phonemes, and words. To produce correct output, the speech recognition system has to filter out the proper word. This is done in the word rejection step. This application can later be installed into our mobile phone, thereafter which the use of a PC is totally not required. The use of a PC will only help facilitate error correction in our code, thus eliminating the chances of later debugging 46

5 Pervasive Home the program code, after it has been installed in our mobile phone. Thus, the spoken command is converted to a text format and text message is generated Designing the GUI for Mobile Phone The GUI for our mobile phone will enable the user to interact with it friendly, and also will guide him to use the speech-to-text (STT) application. The STT application will be automatically loaded when the user presses the * button for more than 10 seconds. The code for this also will be designed using J2ME. Thus, the output of the STT application (text) is sent to the GSM modem, through the mobile service provider, for further processing. 3.3 Circuit Design for GSM Modem The GSM modem receives the text message and it will send it to the input port of the microcontroller. Preceding this, an Analog to Digital Converter (ADC) is used for converting the analog signals to digital signals. The received digitalized text message is then matched with the pre-stored patterns. The matched patterns are processed, and the other patterns will be rejected. The digitalized pattern is then sent to the GSM modem. The pattern is sent through a wired connection between the microcontroller and the GSM modem. 3.4 Firmware Design Firmware is coding a hardware device or rather training a hardware circuit to do the needful. The digitalized text message, which is sent to the wi-fi device through the GSM modem, is later transmitted to the respective GSM modem, situated near the appliance itself. The necessary coding for this is done using assembly language programming. 3.5 Circuit Design for Control of Domestic Appliances The last and the most important phase of the system s development would be the design of the slave circuit. This part of the circuit decides whether the device has to be switched on or off. This is done with the help of the device controller. The device controller is designed using assembly level language programming. The devices are connected to a 220 V supply, interfaced with the help of a device controller. Device controllers can maintain the status of device and monitors the device according to the pattern at the input pins. Device controller is given with different inputs i.e. device select, voltage level input and status input of the device (ON/OFF). 4. DESIGN OF THE SLAVE CIRCUIT The slave circuit involves the processing and hardwired circuitry from the PIC 16F877A microcontroller to the relays. These relays are further connected to individual electrical appliances through hardwire connections. The components of 47

6 R.Ganesan the slave circuit in our system are PIC 16F877A, Relays, Four Different Ports for the home appliances. The slave is in charge of executing what the master has commanded. It does not start processing information until the master is ready to send. However, the slave has a few tasks of its own before it is ready to start the communication. It must have the transistors and resistors in active mode in order to receive signals from the PIC 16F877A microcontroller. The relay driver has the following components Transistor, Diode, Resistor, Relays. 5. PIC 16F877A MICROCONTROLLER Microcontrollers are small computer on a chip with some special properties CPU, code memory, data memory and IO ports all included on a single chip, Dedicated to one task, Small and low cost, Embedded in many consumer devices. PIC is very small and easy to implement for not complex problems and usually accompanies to the microprocessors as an interface. The 16F877A is one of the most popular PIC microcontrollers and it's easy to see why - it comes in a 40 pin DIP pinout and it has many internal peripherals. The 40 pins make it easier to use the peripherals as the functions are spread out over the pins. This makes it easier to decide what external devices to attach without worrying too much if there enough pins to do the job. One of the main advantages is that each pin is only shared between two or three functions so its easier to decide what the pin function (other devices have up to 5 functions for a pin). The PIC16F877A features 256 bytes of EEPROM data memory, self programming, 2 capture/compare/pwm functions, the synchronous serial port can be configured as either 3-wire Serial Peripheral Interface (SPI ) and a Universal Asynchronous Receiver Transmitter (USART). All of these features make it ideal for more advanced level A/D applications in automotive, industrial, appliances and consumer application. PIC DEBUGGING Use a protoboard with RS232 support, program waits for a switch press, reads an analog voltage, changes the PWM cycle accordingly the CCS is accessed through its Integrated Development Environment (IDE). The IDE allows the user to build project, add source code files to the projects, set the compiler options for the project and compiler projects into executable program files. These executable program files are then loaded into the target microprocessor. MPLAB is one of the most popular c compilers for pic microcontroller. It is a cross compiler, where programs are developed on the PC and are loaded to the memory of the target microcontroller using a suitable programming device. 48

7 Pervasive Home 6. REAL TIME IMPLEMENTATION Our system can be used to access home/office appliances from anywhere. The home automation system requires the user to press the * key of the mobile phone device for a short duration so that the STT application is activated and ready to receive the message from the user. This feature is very beneficial as it needs only a key-press to activate the system. As mentioned above, this system is built in order to serve people of all age groups. The user requires only the basic knowledge to work with the mobile phone device. The GUI for the mobile is designed in such ways that even a lay person can know what to do next. The user needs to give the command like FAN ON, FAN OFF, LIGHT ON, LIGHT OFF, BULB ON, BULB OFF, AC ON, AC OFF. This command is recognized by the mobile phone device and converted to text format. This conversion is done by the STT application which is programmed using a high level language (J2ME). The text message is then sent to the GSM modem through the mobile service provider. The GSM modem can receive only text messages and cannot receive calls. The GSM modem receives the text message from the mobile phone device of the user and converts it to digital coding with 0 s and 1 s. Assembly language is used to program the GSM modem to enable the conversion from text message to digital coding. The digital signals are verified or checked using multiplexers and the signal is sent to the corresponding GSM receiver device placed near the home appliance. If the command given is LIGHT ON then the signal is sent to the GSM modem placed near the light. The GSM modem is physically connected to the hardware device. The signal is then sent to the hardware device. Here the signal is verified whether it is on or off then the corresponding activity is carried out by operating the relay. The relay opens or closes the electrical circuit according to the signal received by the hardware device so that the corresponding appliance is triggered. Thus, the home appliances are activated by the user from where ever they are number. FUTURE WORK Technology keeps developing and as it develops, we will see a whole lot of new home automation systems coming up. Our home automation system can be enhanced to perform regulation operations such as turning a fan s speed down or setting the temperature of an air conditioner or a refrigerator. It can also be enhanced in such a way that we can even make sure that the sprinkler system gets activated at a particular set time. The home automation system can also have a provision for feedback. This can be very helpful especially 49

8 R.Ganesan in terms of security. When the burglar alarm goes on, the system can notify the user by sending an SMS to the user s number. CONCLUSION Innovation is creativity, and creativity comes in many forms. We can develop a whole new technology or we can collaborate many different technologies to create a unique new application/system. We have proposed such a similar system which combines the power of GSM modem and the ubiquity of the mobile phone to give birth to a whole new reliable, home automation system. This system will definitely prove to be a great benediction to the physically challenged. REFERENCES [1] Begum, T. Hossain, M.S. Uddin, M.B. Chowdhury, M.S.H Design and development of activation and monitoring of home automation system via SMS through microcontroller, IEEE International Conference on 2009 [2] Jun Hou Chengdong, Wu Zhongjia,Yuan Jiyuan, Tan Qiaoqiao, Wang Yun, Zhou Research of Intelligent Home Security Surveillance System Based on ZigBee, Intelligent Information Technology Application Workshops, IITAW '08. International Symposium on 2008 [3] Tae Gung Kim, Ki Hyung Kim Techniques of home network control using a mobile phone, IEEE 2009 [4] Spoken Dialog System for Next Generation Knowledge Access, Mobile Data Management, MDM '08. 9th International Conference on 2008 [5] A segmental CRF approach to large vocabulary continuous speech recognition, IEEE 2009 [6] Remote Control using Mobile through Spoken Commands, IEEE 2007 [7] A mobile-based home automation system, IEEE