Braille Display

canolaokahumpkaElectronics - Devices

Nov 2, 2013 (3 years and 7 months ago)

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B
RAILLE

D
ISPLAY

Katie and Kara Chylinski

Advisor: Professor Hedrick

March 5, 2005





O
UTLINE


Background


The Problem


Our Objective


Design Process


Final Design


Results


Conclusion

I
NTRODUCTION

Braille Alphabet

Braille Display

M
OTIVATIONS


Combine past class work


Include a variety of topics


Solve a problem


Beneficial to people with disabilities


Have fun!

P
ROJECT
G
OAL

Concerns:

inexpensive, adaptable, portable

S
YSTEM

M
ODULES

Convert printed page to bitmap


Convert bitmap to ASCII characters


Change ASCII to Braille dot pattern


Send dot pattern to display unit

M
ODULE
D
ESIGN

P
ROCESS


Environment: Linux


Collecting bitmap: SANE


Converting bitmap: GOCR


Driver hardware: Cynagal C8051






Microcontroller

This module technique allows us to change each component.

D
EVELOPMENT
S
YSTEM

Scanner

Power

Supply

Display

Cell

Circuit

Program

Microcontroller

C++

Program

Text

D
ESIGN
P
ROCESS


Research


Compare actuators


Design sketches and performance criteria


Configure scanner and optical character
recognition (OCR)


Use microcontroller and RS232 port


Program code changing ASCII to Braille


Construct driver circuit

R
ESEARCH


Freedom Scientific



Pulse Data



ALVA



Metec


A
CTUATORS

Solenoids

Piezoelectric

Speakers

Cost

+

-

++

Size

+

++

-

Voltage

-

+

++

P
ERFOMANCE
C
RITERIA



Cell Dimensions:


Between dots: 2.54 mm


Dot height: .5 mm


Between cells: 3.75 mm


Changing speed

S
OLIDWORKS
S
KETCH

D
ETAILED
S
KETCH

S
CANNER AND
OCR


Devices


Epson SCANNER GT
-
8500


GOCR 0.39


Procedure


Scan in Text


Use Optical Character Recognition


Create “out.txt” File


M
ICROCONTROLLER



RS232 Port


Serial Port


Data Communication


Protocol


Program

SEND

@

WAIT

R

SEND

CHAR

WAIT

S

WAIT

WAIT

@

SEND

R

WAIT

CHAR

SEND

S

Linux

Microcontroller

@

R

char

S

P
ROGRAM




// receive example:


// a '1' turns LED on; a '0‘ turns LED off.



P2MDOUT = 0xff;



XBR2 = 0x40;





P2 = 0x00;




while (1) {






input_char = _getkey();










if (input_char == '@') {













putchar('R');

















//get the braille character

















input_char = _getkey();

















putchar('S');

















P2 = input_char;







}





}

C
++
P
ROGRAM


Algorithm


Set baud rate


Open output file from scanner


Read in first character


Communicate with microcontroller


Check if capital letter or number


Write to port binary sequence

C

++
P
ROGRAM













/* Change ASCII to Braille */
















switch (int(next))
















{
















// Lower Case Letters
















case 101: case 69:















// e
-

010001


















portchar = 0x11;


















write(port, &portchar, 1);
























break;
















case 116: case 84:















// t
-

011110


















portchar = 0x1e;


















write(port, &portchar, 1);
























break;
















case 97: case 65:

















// a


000001


portchar = 0x01;


















write(port, &portchar, 1);
























break;


D
RIVER
C
IRCUIT

R
ESULTS

R
ESULTS

a

R
ESULTS

b

R
ESULTS

c

T
OTAL
C
OST

Scanner:







$50

Microcontroller:




$150

OCR software:




free

6 Solenoids:



$20

Circuit components:



$10

Casing materials:


+


$20









$250

S
UMMARY

F
UTURE
W
ORK


Finish mechanical casing


Improve scanner


Improve OCR


Run SANE from C++ program


Make portable

R
EFERENCES


http://dots.physics.orst.edu/gs_index.html

http://jocr.sourceforge.net/

http://www.aagi.com/

http://www.allelectronics.com/

http://www.alva
-
bv.nl/alvacorp/alva_corp_home.asp

http://www.askoxford.com/asktheexperts/faq/aboutwords/frequency

http://www.braillenet.net/accessibilite/livreblanc/english/affbraille.html

http://www.freedomscientific.com/

http://www.htwm.de/acmc/mcmodule.htm

http://www.k10k.net/issues/issue059/golan/dakadaka/braille.html

http://www.kgs
-
america.com/bc.html

http://www.metec
-
ag.de/english.html

http://www.nec
-
tokin.com/english/product/sekisou_e/pa_features.html

http://www.pulsedata.com/

http://www.sane
-
project.org/

http://www.vesid.nysed.gov/lsn/stvnews/fall03.htm


A
CKNOWLEDGEMENTS

Professor Hedrick

Eugen Schäfer

Roland Pierson

James Howard

Gene Davison

Q
UESTIONS?