08-05-2013, 02:28 PM
GPS Based Voice Alert System for the Blind
GPS Based Voice.pdf (Size: 274.63 KB / Downloads: 216)
Abstract
GPS is employed to find the position of the user on the earth. This information is provided by the GPS with the help
of the data it receives from the satellites. GPS based voice alert system for the blind uses the current location and gives the
alert to the blind man if it was his destination area. This paper describes the concept using a microcontroller based system. The
system has a dynamic user interface and is easily operable. The system is realised using a GPS module (SR-92) and a Voice
Module (APR9600) interfaced with a PIC16F877 microcontroller. The working of the system incorporates two stages; first the
location based audio recording stage and second, the navigation of the blind person using the signal from the GPS receiver. The
system employs a user friendly design and provides for an automatic location name announcement system.
INTRODUCTION
he Global Positioning System (GPS) is a U.S. spacebased
radio navigation system that provides reliable
positioning, navigation, and timing services to civilian
users on a continuous worldwide basis. For anyone
with a GPS receiver, the system will provide location and
time. GPS provides accurate location and time information
for an unlimited number of people in all weather,
day and night, anywhere in the world.
GPS based blind man device with user input interfacing
(voice based) intellectually finds the current location and
gives the alert to the blind man if it was his destination
area.
Microcontroller is the heart of the device. It stores the
data of the current location which it receives from the
GPS system, so that it can make use of the data stored to
compare with the destination location of the user. By this
it can trace out the distance from the destination and produce
an alarm to alert the user in advance.
This device is designed to provide a voice based announcement
for the user, i.e, the user gets the voice which
pronounces his destination location as and when he is
about to reach the destination. Here instead of an alarm
sound the blind man can directly hear the location recorded
by the user itself.
Hardware
Voice Module (APR9600)
A P R9600 is a low-cost high performance sound
record/replay IC incorporating flash analogue storage
technique. Recorded sound is retained even after power
supply is removed from the module. The replayed sound
exhibits high quality with a low noise level. Sampling rate
for a 60 second recording period is 4.2 kHz that gives a
sound record/replay bandwidth of 20Hz to 2.1 kHz.
Microcontroller
T h e microcontroller used for this system is
PIC16F877A. The PIC families of microcontrollers are
developed by Microchip Technology Inc. Currently they
are some of the most popular microcontrollers, selling
over 120 million devices each year.
Regulated Power Supply
A device or system that supplies electrical or other
types of energy to an output load or group of loads is
called a power supply unit or PSU. The term is most
commonly applied to electrical energy supplies, less often
to mechanical ones, and rarely to others.
A power supply may include a power distribution system
as well as primary or secondary sources of energy
such as
Conversion of one form of electrical power to another
desired form and voltage, typically involving converting
AC line voltage to a well-regulated lowervoltage
DC for electronic devices. Low voltage, low
power DC power supply units are commonly integrated
with the devices they supply, such
as computers and household electronics.
Software
Express PCB
This software is used for designing the circuit. Breadboards
are great for prototyping equipment as it allows
great flexibility to modify a design when needed; however
the final product of a project, ideally should have a
neat PCB, few cables, and survive a shake test. Not only is
a proper PCB neater but it is also more durable as there
are no cables which can yank loose.
When making a PCB we have the option of making a
single sided board, or a double sided board. Single sided
boards are cheaper to produce and easier to etch, but
much harder to design for large projects. If a lot of parts
are being used in a small space it may be difficult to make
a single sided board without jumpering over traces with a
cable. While there’s technically nothing wrong with this,
it should be avoided if the signal travelling over the traces
is sensitive (e.g. audio signals).
CONCLUSION
The system designed consists of a GPS receiver and a
voice circuit which is interfaced to the microcontroller.
The microcontroller is programmed in such a way that
depending on the satellite information of location the
predefined location name will be announced.
The only major disadvantage of this system is the time
taken by the GPS to receive its initial signal from the satellite,
i.e, when it is switched ON. The above disadvantage
can be removed by using a higher efficiency GPS
receiver.