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


Presentation Outline:

17/6/2011Dept of ECE, Govt.S.K.S.J.T.I. 3

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


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.


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.


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.


Overview of the project


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


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


Hardware requirements


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

17/6/2011 12

1 Satellite 2 Satellites

3 Satellites

17/6/2011

Dept of ECE, Govt.S.K.S.J.T.I.

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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


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

Dept .of ECE,GSKSJTI 15

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,


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


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


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


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.


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.


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.


17/6/2011

23Dept of ECE, Govt.S.K.S.J.T.I.

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

Dept of ECE, Govt.S.K.S.J.T.I. 25

Actual Demonstration

C

A B

1

2

3

45 6 78910

17/6/2011

Wearable deviceAudio guidance system in local language. It can be used for outdoor applications.Cost effectiveCapable of detecting obstacles and pit

detection.


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.


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.


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.


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.


References


Hardware designMAIN STATION


SUBSTATION

GPS for blinds

Documents

Transcript of GPS for blinds