Download - GPS for blinds
Presented By Chandana.K.S (1SK07EC011)
Swathi K.N (1SK07EC055)
Shalini B (1SK07EC046)
Bhaskar.V (1SK07EC010)
COMBINED SCHEDULING OF ULTRASOUND AND GPS IN A
WEARABLE GUIDANCE SYSTEM FOR THE BLIND
17/6/2011 1Dept of ECE, Govt.S.K.S.J.T.I.
Under the guidance Of
Prof. M.V. JyothiDept of ECE
Govt.S.K.S.J.T.I
Introduction Available technologies Statement of the problem Objective Overall architecture Advantages Limitations Future enhancement Conclusion
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Presentation Outline:
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IntroductionAccording to WHO
estimation around 2.6% of the world population are visually impaired.
One of the difficulty they face everyday is finding their way.
What happen if a blind is in trouble while he is on the road? Fig: Global estimation of visual
impairment by WHO region
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Available technology
Currently blind consumers can choose from four GPS products:
1. Talking Signs2. Smart Canes3. Sonar vision glasses4 SWAN systems On Going Research In
Various Universities
These devices cannot inform a blind traveller about drop-off on the sidewalk or a rise in elevation.
cannot determine ordinary obstacles.cannot guarantee safety for a blind
traveller.These devices are hand held.More expensive.
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Statement of the problem
To design and develop a small, simple, wearable and affordable guidance system for the poor blind.
To develop navigation device which is capable of detecting any obstacles.
To develop energy efficient wearable device.
To develop GPS based navigation device with audio guidance in local language.
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Objective
We designed wearable RF-based guidance system in which a main controller collects GPS signals and ultrasound signals from sensors attached to sub stations and provide appropriate directions to the blind person.
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Overview of the project
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MAIN STATION
Microcontroller
Head set or
speaker
Voice processing chip
GPS Receiv
er
MAX232 Convert
er Decoder
Receiver
315MHz
Ultrasonic sensor3
keypad
Decoder
Receiver
433.92MHz
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SUB STATION 1
ENCODER HT640 ENCODER HT640
ULTRASONIC SENSOR1
ULTRASONIC SENSOR1
TRANSMITTER 315/433.92 MHz
DATA ANT
TRANSMITTER 315/433.92 MHz
DATA ANT
PIN2
PIN1 PIN8
PIN2
PIN4
DATAOUT AD11 DOUT
GPS receiverMicrocontrollerSensorsTransmitters and receivers Encoders and decoderMAX 232Single chip voice recorder
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Hardware requirements
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Module descriptionGLOBAL POSITIONING SYSTEM (GPS)a
GPS is a space-based global navigation satellite system (GNSS)
• 24+ satellites• 20,200 km altitude• 55 degrees inclination• 12 hour orbital period• 5 ground control stations• Each satellite passes over
a ground monitoring station every 12 hours
3-D Trilateration
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1 Satellite 2 Satellites
3 Satellites
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GPS -634R 65 channels to acquire and
track satellites simultaneously
Tracking sensitivity reaches -161 dBm
Accuracy 5m CEP Operable at 3.6V-6V Both of RS232 and UART
interface at CMOS level Small form factor of 32 mm
W x 32 mm Lx 8 mm H Mountable without solder
process 6 pins wafer connector
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MICRO CONTROLLER
The AT89C52 Microcontroller 8 bit computer
8KB in-system programmable flash memory
4v to 5v operation rangeFull duplex UART serial
channel.Eight interrupt sourcestake over the control of
entire system
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MAX 232
Operates From a Single 5-V Power Supply With 1.0-F Charge-Pump Capacitors
Operates Up To 120 kbit/s Two Drivers and Two
Receivers ±30-V Input Levels Low Supply Current . . . 8 mA
TypicalApplications− TIA/EIA-232-F, Battery-
Powered Systems,
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ENCODER
HT640 Operating voltage: 2.4V~12V Low power and high noise
immunity CMOS technology Low standby current Built-in oscillator needs only
5% resistor Easy interface with an RF or
infrared transmission media Minimal external components
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DECODER HT648LOperating voltage: 2.4V~12V Capable of decoding into 18 bits of
information 8~18 address pins, 0~8 data pins Built-in oscillator needs only a 5%
resistor Valid transmission indictor Easily interface with an RF or an
infrared Minimal external components
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TRANSMITER
TXC1315/433.92 MHzThe TXC1 is an ASK
transmitter module .The TXC1 is operates at
315/433.92 MHzVoltage 2.2-5.5v, Icc
10mAData rate 300-10k bps
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RECEIVER
RXC1A radio receiver, that
receives its input from an antenna
Uses filters, amplifiers, demodulators and decoders.
The receiver system's frequency is 315/433.92Mhz.
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Ultrasound sensorsPower voltage: DC 6-
12Vquiescent current: less
than 2 m AOutput level: high 5VOutput level: low 0VSensing angle: no greater
than 15 degSensing distance: 2mm-3
meters.
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Single chip voice recorder
non volatile storageback ability for 40 to 60
secondseasy to use so there is no need
to program or develop it.In our project we use Random
Access 8 fixed duration messages mode.
play back can be made randomly in any of the selected messages.
SOFTWARE REQUIREMENTKeil micro-vision 3ProloadHyper-terminal.
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FLOWCHART
Yes
No
Yes
No
Yes
No
If the position match zone_n
Play voice message
relate with
zone_n
If the position
match zone_1
Play voice message
relate with
zone_1
Extract position information
Skip the first 9 characters of GPGGA. Read next 24 characters of GPGGA which represent Latitude and Longitudinal components of position
Display the position information on LCD
Is GPGGA fix data detect by GPS receiver?
System On
End
Interrupt from the sensor
Stop the execution of the main program
Go to the corresponding Interrupt
Service Routine
Come back to the main program
3 boards : 1. Main station
2. sub station 1
3. sub station 2All 3 systems are wearable.The main station placed in pocket. Substation 1 is placed in the hand for the detection of pit, man hole,
and obstacle.Sub station 2 is placed on the knee for the detection of sideway
moving or stationary obstacle. Person wearing this system moved in a pre-defined path.Destination is selected through keypad, the audio information is
provided from system and also display in LED.17/6/2011 24Dept of ECE, Govt.S.K.S.J.T.I.
Implementation aspects
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Actual Demonstration
C
A B
1
2
3
45 6 78910
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Wearable deviceAudio guidance system in local language. It can be used for outdoor applications.Cost effectiveCapable of detecting obstacles and pit
detection.
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Advantages
GPS system can't use it indoor building or closed
area.The storage capacity of APR9600 voice
recorder is relative small .GPS system is not very accurate.
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limitations of projects
A combination of GPS and RFID technology could
be successful in the future.This system can also be used to provide bus
route information.This system can also be designed to give
route information of hole city. Instant changes in path can also be given
with the GSM technology.
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Future enhancement
In this project we designed a wearable audio system for the blind to travel easily without asking anyone and it also provides an information about obstacles through audio signals.
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Conclusion:
“Combined scheduling of ultrasound and GPS signals in a wearable ZigBee-based guidance system for the blind” 978-1-4244-4316-1/10/$25.00 @2010 IEEE.
“GPS Talking For Blind People” JOURNAL OF EMERGING TECHNOLOGIES IN WEB INTELLIGENCE, VOL. 2,
NO. 3, AUGUST 2010“GPS navigator for blind walking in a
campus” world academy of science, engineering and technology 70 2010.
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References
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Hardware designMAIN STATION
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SUBSTATION