Mobile phone is a really utile innovation. Today all the people are utilizing nomadic phones for their convenient the nomadic phone is a really good engineering for communicating. Having nomadic phone is a great advantage for pass oning with friends and households from anyplace to all over in the universe. By naming or directing messages from nomadic phone we can easy able to link with others without electricity.
Now a twenty-four hours ‘s SMS ( short message service ) is the most utile application. Today 80 % of nomadic phone users are utilizing this information application. But the visually impaired people can non able to utilize this application.
In this undertaking the visually impaired people can read message utilizing nomadic phone, and besides this system assist the unsighted people to direct recognition for the current entrance messages.This will be implemented by interfacing the Braille system with nomadic phone.
Louise Braille is the male parent of Braille system. This system is a world-wide system ; with the aid of this system, all the blind peoples for reading and composing like a normal people.
It was invented by Louise Braille ( 1809-1852 ) , who was blind and go a instructor of the blind. Braille is the system to compose and read the words by touch for the visually impaired people. Old yearss the Braille system is used merely for the reading intent. Now merely the system convert to utilize both read and write.
It consist of forms of set uping points in array mode and all the points all arranged in 3×2 constellation. Each cell represents a peculiar missive or symbol and the combination of Braille cells mention the words or sentences.
There are figure of different versions of Braille:
Grade 1 is consists of 26 letters of standard alphabets and punctuations. This is foremost get downing system for the unsighted people.
Grade 2 is besides consists of 26 letters standard alphabet and punctuation. Besides this class has the contractions. Braille page can non suit into printout page. So utilizing contractions we match the Braille and take printout pages.
Grade 3 is chiefly used for personal letters, journals and besides literature. This type of stenography written is largely used for the message applications.
Braille codification is the universe foremost binary encoding strategy to stand for the letters in the authorship system.
The system is invented by in two parts:
In the Gallic linguistic communication, character encryption is used for mapping characters in the signifier of six points. By raising the points they can place their characters.
Braille alphabet ( English Braille American edition )
Braille Alphabet Card ( rate one )
Braille punctuation marks
Today different Braille codifications are used to advert the different linguistic communications by six spot cells. Because of the six-dot Braille cell merely have 63 combinations. In this diagram, some same oriented character omitted based on their context. So merely the characters are non mapping to each other letters.
The chief aim of this undertaking is unsighted or partly blind people can understand the messages and give recognition for peculiar message utilizing nomadic as normal people.
Braille engineering is doing of revolution among the visually impaired people. This Braille engineering allows blind people to make many things like authorship, shoping the cyberspace, typing Braille and printing in text papers, typing in confab, downloading files, music, utilizing electronic mail and for reading paperss. It is besides utile for unsighted pupils for finishing their assignments like a normal pupil.
Braille is most utile engineering for the unsighted people in communicating universe. In the bing system message application dose non complete for unsighted people. In message application the visually impaired people merely can able to read the message in on the haptic surface of the show. But the quality of the system is non good because the unsighted people non able to place the text precisely
In this system the message received from the GSM modem. Every individual entrance message is indicated by external quiver motor utilizing quiver. The every individual message roll uping in the arm board, will be display in these formats ( LCD show, Braille board and voice end product ) by pressing cardinal figure ” 1 ” in the control unit.
Fig 1 Block diagram of message application utilizing Braille system
Here LCD is used for all except unsighted people, but end product message from the sound is used for blind and dense people merely. Both Braille end product and audio end product can be used by the unsighted people. The entrance message which is non of import for the user can be deleted by utilizing control unit ( cardinal no: 3 ) .
The user can answer the current message by utilizing input voice from mike ( mic ) . After finishing voice record the voice input convert into text automatically in the ARM board. Before directing that answer text message is look into the enchantment by utilizing Braille board when pressing the cardinal “ 6 ” in control unit. Finally the message is sent through the GSM modem by imperativeness the cardinal “ 9 ” .
V. CONTROL UNIT
This system is chiefly developed for nomadic application. By utilizing this system the blind people could read and compose message by Braille faculty. So merely we are implemented all these system maps in to one control unit is called computer keyboard.
Control unit have 12 keys ( 0 to 9, # and * ) for commanding the full system. Each key have specific map in that unit. Blind people, every clip when pressing a key, the indicant of cardinal which pressed that will be indicated in loud talker.
Functions of control unit:
1. Ready to read
3. Delete current message
4. Answer for current message
5. Voice record, Voice record complete
6. Check text
8. Re-voice record
9. Send message
* . Temperature indicant
0. Time indicant
# . Date indicant
Vibration: It is first map of this undertaking, If any new message is comes into the Mobile, the indicant of new message to get down vibrating utilizing mini quiver motor.
Ready to read: After vibrating, we can read that message by utilizing imperativeness the cardinal “ 1 ” . These command to make a undertaking into the accountant for reading new message to change over “ text message in to voice ” and delivered in to loud talker. This procedure is called Speech synthesis. The message besides indicated in LCD show and Braille board.
Reread: The blind may can non read the message clearly the first clip, press the cardinal “ 2 ” so the that current message once more indicated in three format.
Delete the current message: If that current reading message is non of import message, want to cancel that message so press the cardinal “ 3 ” . The current message is deleted from the inbox.
Reply for current message: Want to answer for that current reading message, press the cardinal “ 4 ” . This is bespeaking to the accountant for ready to enter the voice for recognition.
Voice record: After bespeaking the ready to voice record, press the cardinal “ 5 ” to get down entering the voice from the mike input.
Voice record complete: Want to finish the recoding voice input, once more by pressing the cardinal “ 5 ” in control unit. Here the voice entering procedure complete, so get down the procedure of the voice change overing into text. This is the get downing procedure of the address acknowledgment. This undertaking is to originate the address acknowledgment in the accountant, after change overing address into text, so the text stored in the accountant United Nations boulder clay Waiting for enchantment cheque before directing message.
Check text: The stored text message is look intoing by utilizing Braille board when pressing the cardinal “ 6 ” . Here the each character of the message show in the Braille board besides delivered in the loud talker and LCD show.
Recheck: If the look intoing the text is non compatible for the unsighted people, so recheck the text by pressing the cardinal “ 7 ” .
Re-voice record: If the text is non right or any spelling error is at that place agencies, want to re voice record for rectifying the message by pressing the cardinal “ 8 ” . Then above all the procedure re-do before directing message.
Send message: The text message is right after look intoing enchantment so press the cardinal “ 9 ” . The message sent to the peculiar receiver.
Temperature indicant: The unsighted people can see the conditions and temperature of the environment. When pressing the cardinal “ * ” the temperature of the current twenty-four hours to delivered in loud talker.
Time indicant: When imperativeness the cardinal “ 0 ” , current clip will be delivered in the loud talker besides display in LCD.
Date indicant: When imperativeness the cardinal “ # ” , day of the month of the current twenty-four hours will be delivered in the loud talker besides display in LCD.
Braille system works in two type of mechanism:
Using an electro-mechanical technique the Braille show is raising points through holes in a level surface for exposing Braille characters.
The 2nd mechanism, which is utilizing piezoelectric consequence to raises the points when a electromotive force applied to it. The crystal connected to the lever, which raises the points. This mechanism is high cost comparison to electro mechanical show.
VI. ELECTRO MECHANICAL MECHANISM
A flapper has high mechanical stableness, low triping electromotive force, and low monetary value compared piezoelectric mechanism. Each Braille cell has modular unit, called Braille cell faculty. It consists of six flappers to drive the Braille points.
A. Flapper actuator:
The flapper works based on the theorem of electromagnetic rule. Inside the enamelled spiral there is fixed Fe nucleus ; flapper actuator moving as a rotatable armature. The enamelled spiral is constructed in spiral form and it carries electric current and produces the magnetic field lines. The enamelled spiral increases the magnetic field. The pole of Fe nucleus is moving as a strong magnetic field. And it attracts the armature for control the Braille pin. This mechanism of flapper moving rule shows in figure 2. Here a yoke is used to suit the Fe nucleus and to increase the magnetic field. An armature attractive by Fe nucleus and pushes the Braille pin upward. An armature cartridge holder has limited grade of freedom ( DOF ) of armature in one way.
Fig.2 Flapper actuators and Braille cell mechanism.
Braille pins and flappers are depends on the figure of Braille point ‘s. The flapper has two opposite operations in this technique. One is no current base on ballss through the enamel spiral and no magnetic force is created to pull the armature. Second status is the enamel carrying current, the current base on ballss through the enamel spiral, and the armature is attracted by upwards because of lever mechanism. The point e2 in armature is clipped by armature cartridge holder and that armature rotate in z-axis because of DOF. Point e3 is lifted to reach Braille pin when the point e1 attracted to press nucleus. Finally Braille pin pushes upwards.
The angle between e1e2 and e2e3 can alter because of perpendicular shot at point e3. e2e3 is an horizontal place, when the flapper is non transporting current and that clip little alterations in angle between perpendicular line and e1e2.
The angle R can be estimated easy when the stoke move upwards and make 0.7mm. This specific length ratio is to declare the upward shot of Braille pin to three clip of the air spread between the armature and Fe nucleus. The little infinite of air spread in the flapper will be used by this design to supply a big stoke of Braille pin. Main advantage of this air spread is to cut down the current and for less heat coevals.
B. Fabrication of Braille cell faculty and Braille show:
Harmonizing to types of armature there are two types of armature, and harmonizing to their lengths three type of Braille pin are at that place. The assortment of flapper and Braille pins are used to specialise design and adjustment in Braille cell faculty. Here Braille cell mechanism has six Braille pins and six flappers. The figure 3 shows a Braille cell faculty.
Fig.3 Fabrication of Braille cell faculty
The full map of Braille cell shows in the figure 2. Six flappers are in the circuit board with haptic surface. And the tactile surface has six holes for keeping six Braille pins. The utilizations of finger tip on the surface, we can place which pin is to be raised and which missive are mentioned.
VII. SPECIFICATION FOR BRAILLE DOTS
Refreshable Braille specifications are listed in below specification tabular array. The values are listed below are best fit value for current criterion Braille system.
The top of the Braille points are domed. The each domed has unspecified radius of curvature.
When point is raised, the peculiar point should be supported by force of & gt ; 25 gms.
BRAILLE DOT SPECIFICATION
Braille point base diameter
Height of 8 points Braille cell lines
Distance between centres of matching points in the same cell
Distance between centres of matching points in horizontally next cells
Height of 6 points Braille cell lines
When the Braille reader touch the surface, the Braille pin should supply a lower limit of 20 gms lifted force, while depressed & lt ; 0.1 millimeter from its top tallness.
Dot tallness should be uniformly for next points: A±0.05 millimeter. Minimum supplanting of the un-raised point in below reading surface value: 0.025 millimeter.
Measuring of Braille line spacing and height utilizing the Centres of a top point of the cell and besides see vertically next cell.
Braille construct besides used in haptic show, if it has extra points to make full in the spreads of between Braille cells and Braille graphs between cells within cells of each line.
VIII. SPEECH SYNTHESIS
Speech synthesis is the procedure of developing a human address in an unreal mode. This system is called speech synthesist. It can be implemented in hardware or package. Here, text to speech ( TTS ) system used to change over the normal text message into address. The relevant address for each text already created and stored in the information base. Each system has different size of informations base unit ; the address unit that stored in phones or diphones, but it may miss lucidity of end product.
Diphone synthesis is entering a passage between the phones. Number of diphones depends on the linguistic communication content. These diphones are used to hive away the words and better the quality of the end product of address. Synthesizer is an instead used to place the theoretical account vocal piece of land and besides creative the wholly man-made of other human voice end product.
The quality of this system increased when the similarity of human voice into the database and ability to understood the voice. This system largely used by the visually impaired people to reading the message and computing machine paperss. The figure 4 shows the block diagram of speech synthesis.
Fig.4 Speech synthesis
A text-to-speech system is composed of two parts:
AA front-endA 2 ) AA back-end
First, it converts the text message ( Numberss, abbreviations ) into equivalent of written out words. This procedure is called pre processing. The front terminal assigns phonic written texts and that converts into the corresponding address, besides lucifer to the system database ; the procedure of change overing phonic written texts into words is called grapheme-to-phoneme transition. Finally in the front terminal phonic written texts converts end product as symbolic representation. The back terminal is the end product terminal ; this is used symbolic lingual representation into sound. in this system the corresponding end product address is delivered in the talker.
IX. SPEECH RECOGNITION ( SR )
Here speech acknowledgment is the interlingual rendition of marked words into text message. It is besides called automatic address acknowledgment or address to text ( STT ) .
This is a computing machine engineering that is used to acknowledge and understand the input address, by utilizing digitising and fiting with the database. Now a twenty-four hours ‘s all the available devices are speaker dependant, it can acknowledge one or two individual merely. Besides recognize distinct address so normal address. This engineering is chiefly used for assisting people in working around their disablements. In this undertaking STT utilizing message application is chiefly for assisting visually impaired people ; it convert the input speech signal into matching text message. Before utilizing this engineering, we supposed to better the quality of the system by developing with specific individual voice in the database ; it is called “ talker dependant ” system and it gives more accurate written text.
Fig.5 address acknowledgment block diagram
The system will non be trained agencies that is called as talker independent systems. Natural modulation for the synthesised address will be generated by inflection generator. A flexible pitch contour is selected to accommodate the type of the sentence from the database. Figure 5 is shows the block diagram of address acknowledgment.
For a given input text message, modulation for the sentence is determined based on nature of the sentence and so it bring forthing the corresponding pitch contour ; the address units extracted from system database. Flip and clip graduated table alterations are cod out in harmonizing to the pitch contour. Finally, trained speech units are performed to bring forth address of the end product.
Still now Braille engineering is used by the blinds merely for the reading intent. But here, utilizing this Braille system both reading and answering the messages possible by visually impaired people. In this undertaking utilizing Braille engineering the unsighted people can entree the message application in Mobiles as a normal people. Using this system uneducated people besides may utilize the message application in Mobiles.