31-08-2016, 11:51 AM
1451715493-eswar.pdf (Size: 149.12 KB / Downloads: 26)
Abstract: The increased growth in the railway sector has resulted in an increase in the train traffic density across the
world. This has resulted in the increase in the number of accidents involving trains. In this paper, the proposed system
includes several features which prevent train accidents. It includes automatic speed controlling in curves, collision
detection, fire detection, detaching of couch automatically when fire is detected in it, automatic railway gate control
and track continuity. This system makes use of IR sensors, fire sensor, zigBee and other embedded systems.
INTRODUCTION
The Indian Railways has the world's fourth largest railway
network in the world, after that of the United States,
Russia and China [3]. The railways traverse the length and
breadth of the country and carry over 20 million
passengers and 2 million tons of freight daily. It is one of
the world's largest commercial or utility employers, with
more than 1.6 million employees. About 15000 trains
work every day. Unfortunately there have been many
accidents involved in the railways.
The Railways has the most intricate and involved interdependencies.
Safety on the Railways is the end product of
the cohesive fusion of its myriad parts. A single flaw in
the 64,600 route kms of track that criss-cross the country,
a defect in over 9,500 locos, 55,000 coaches and 2.39
lakhs wagons that haul about 23 million passengers and
nearly 2.7 million tons of freight every day, an incorrect
indication on one of the thousands of signals that dot the
rail landscape, a mistake or an act of negligence by one of
its staff directly associated with train running, even a rash
act by one of the millions of road users who daily
negotiate around odd level crossing gates spread across the
system, an irresponsible act of carrying inflammable
goods – any one of these multiple possibilities has the
potential to cause a major tragedy. Added to these are the
acts of sabotage by misguided elements spanning the
whole country, Thus utmost vigil is safety in operations
and also security of the traveling public.
II. VARIOUS IMPORTANT COMPONENTS OF ADVANCED
RAILWAYS ACCIDENT PREVENTION SYSTEM
Some of the major components utilized in this system are
microcontrollers, IR sensors and zigbee.
A. AT89S52 Microcontroller
The AT89S52 is a low-power, high-performance CMOS
8-bit microcontroller with 8K bytes of in-system
programmable Flash memory. The device is manufactured
using Atmel‟s high-density nonvolatile memory
technology and is compatible with the industry-standard 80C51 instruction set and pinout. The AT89S52 provides
the following standard features: 8K bytes of Flash, 256
bytes of RAM, 32 I/O lines, Watchdog timer, two data
pointers, three 16-bit timer/counters, a six-vector two-level
interrupt architecture, a full duplex serial port, on-chip
oscillator, and clock circuitry. 32 I/O lines can be used to
output data and order other devices to do certain work, or
to read the state of a sensor, or a switch. Most of the ports
of the 89S52 have „dual function meaning that they can be
used for two different functions.
B. IR Sensors
An infrared sensor is an electronic instrument that is used
to sense certain characteristics of its surroundings by
either emitting and/or detecting infrared radiation. It is
also capable of measuring heat of an object and detecting
motion. Infrared waves are not visible to the human eye.
A typical system for detecting infrared radiation using
infrared sensors includes the infrared source such as
blackbody radiators, tungsten lamps, and silicon carbide.
In case of active IR sensors, the sources are infrared lasers
and LEDs of specific IR wavelengths. Next is the
transmission medium used for infrared transmission,
which includes vacuum, the atmosphere, optical fibers.
Finally, the infrared detector completes the system for
detecting infrared radiation. The output from the detector
is usually very small, hence pre amplifiers coupled with
circuitry are added to further process the received signals.
C. Zigbee Device
ZigBee standard is managed by the Zigbee Alliance, a
global consortium of more than 50 companies (OEMs, IC
vendors & tech companies). ZigBee is a short-range, lowdata-rate
wireless network technology, which is based on
the IEEE 802.15.4 wireless personal area network
standard. And the ZigBee‟s data rate is between l0 Kbit/s
and 250 Kbit/s, so it is suitable for low-rate wireless
transmission applications. But ZigBee can build up to a
few tens of thousands of wireless transmission module
consisting of wireless-data transmission network platform
through the network node, which is very similar to the existed CDMA mobile communications network or GSM
Network. And each network node can extend the distance
from the standard 75 meters to several hundred meters,
and even a few kilometers. And ZigBee network primarily
for the automatic control and the establishment of data
transmission but the mobile communications network for
voice communications is established, which is the
difference between ZigBee network and the mobile
communications network. ZigBee technology has low data
rate and the characteristics of the smaller range of
communication, which also determines the ZigBee
technology is suitable for carrying data traffic smaller
business. ZigBee which is based on the 802.15.4 protocol
stack standards possess a powerful networking capability.