01-02-2013, 11:06 AM
VOICE OPERATED OUTDOOR NAVIGATION SYSTEM FOR VISUALLY IMPAIRED PERSONS
VOICE OPERATED OUTDOOR.pdf (Size: 359.95 KB / Downloads: 117)
Abstract
Blind People uses white canes to aid in obstacle
detection & avoidance. Guide dogs can also be of limited
aid for finding the way to a remote location. So our goal is
to create a portable, simple less costly system that will
allow Blind peoples to travel through familiar and
unfamiliar environments without the aid of guides.
Several guidance system has been developed for vision
impaired people, but these systems tends to be expensive,
also make use of a client server approach. This Navigation
system consists of two distinct components: sensing of the
immediate environment for blind people to travel (e.g.,
obstacles and hazards) and navigating to remote
destinations beyond the immediately perceptible
environment. The paper described here focused on the
development and evaluation of a Navigation system that
makes use of GPS (the Global Positioning System), voice
and ultrasonic sensor for obstacle detection.
INTRODUCTION
According to survey done India is now home to the world's
largest number of blind people. Of the 37 million people
across the globe who are blind, over 15 million are from
India.[5] So in India blindness is the biggest problem. The
leading causes of blindness are cataract, uncorrected refractive
errors, glaucoma, and macular degeneration.
India’s current population is 1.22 billion. Due to
this huge population there is a lot of traffic in the road and in
today’s world no one has time even to talk with each other
especially in metro cities. So the blind people or vision
impaired person feels alone in this environment. People who
have impaired vision regularly use white canes and/or guide
dogs to assist in obstacle avoidance. Guide dogs can also be of
limited assistance for finding the way to a remote location,
known as “way finding” So our goal is to create a portable,
METHODOLOGY
The block diagram of main board is shown in fig.2. In this
diagram using the 32-bit ARM processor (LPC2148), this is
the heart of this project. The LPC2148 microcontrollers are
based on a 16-bit/32-bit ARM7TDMI-S CPU with real-time
emulation and embedded trace support, that combine
microcontroller with embedded high speed flash memory
ranging from 32 kB to 512 kB. A 128-bit wide memory
interface and unique accelerator architecture enable 32-bit
code execution at the maximum clock rate. For critical code
size applications, the alternative 16-bit Thumb mode reduces
code by more than 30 % with minimal performance penalty.
HARDWARE DESCRIPTION
MICROCONTROLLER
Controller used will be ARM LPC2148 which is
based on 32/16 bitARM7TDMI-S CPU with real-time
emulation and embedded trace support that combines the
microcontroller with embedded high speed flash memory
ranging from 32 kB to 512 kB. It has many important features
like. 16/32-bit ARM7 microcontroller in a tiny package. It has
on-chip static RAM and on-chip flash program memory. It
offers real-time debugging and high speed tracing of
instruction execution. USB 2.0 Full Speed compliant Device
Controller.10 bit A/D converters. Multiple serial interfaces
including two UARTs. Low cost, low consumption, easy
handling and flexibility. These features make controller
reliable for the project.[7]
AUDIO AMPLIFIER (LM -386)
The LM386 is a power amplifier designed for use in low
voltage consumer applications. The gain is internally set to 20
to keep external part count low, but the addition of an external
resistor and capacitor between pins 1 and 8 will increase the
gain to any value from 20 to 200. The inputs are ground
referenced while the output automatically biases to one-half
the supply voltage. The quiescent power drain is only 24
milliwatts when operating from a 6 volt supply, making the
LM386 ideal for battery operation.[8]
GPS Receiver (SiRFstarIII GR-301)
NaviSys GR-301 is a low-power, ultra-high performance, easy
to use GPS receiver based on SiRF’s latest third generation
single chip. Its low power consumption and high performance
enables the adoption of AVL and other location based
applications. It supports different electrical interfaces such as
USB, RS232, TTL etc. The connector interface and cable
length could also be customized based on MOQ. The standard
NMEA0183 outputs data using datum of WGS-84.[10]
CONCLUSION
As we have discussed that India is now home to the world's
largest number of blind people and India’s current population
is over 1.22 billion. Earlier majority of visually impaired
people prefer to not use electronic aids, and use only canes or
guide dogs. The underlying reasons for this include the
relatively high costs and relatively poor levels of user
satisfaction associated with existing electronic systems. So we
tried to develop a low cost and user friendly system for blind
people with greatest possible accuracy. In this project we have
used ARM processor which contains more memory and its
operating speed is high. We have use ultrasonic sensor for
obstacle detection instead of white cane. We guide or navigate
the blind people using voice. However, there are still
limitations of our system. Our system cannot work indoors
because no signals can be received from the GPS navigation
system. On the other hand, the accuracy of the signals from
the GPS navigation system still needs to improve although we
can control it within 5 meters.