19-03-2012, 04:44 PM
SIMULATION OF AN ANTI-COLLISION SYSTEM ON SAME TRACK FOR
RAILWAYS
IJEST10-02-09-166.pdf (Size: 788.64 KB / Downloads: 211)
ABSTRACT
This work is concentrated on predicting the major cause of railway accidents that is collision on the same
track. For this purpose some advanced technology to identify train positions, collision detection as well as the
points at where collisions may occur have been used. The primary goal of our anti-collision system is to
identify such collision points and to report these error cases to main control room, nearby station as well as
grid control stations. So that if any collision likely to occurs then our system will help to avoid such conditions
by giving an alarm to concern units. To build this system, advanced sensing technology, long distance
communication system (RS 485protocol), microcontroller (8051) and wireless Communication protocol has
been used. This practical system is then modeled (coded) and simulated using Proteus software, to real like
Condition to identify anti -collision systems utility in predicting different real railway track collisions cases.
proposed to prevent collision:
The Anti-Collision Device (ACD) is a self-acting
microprocessor-based data communication device designed and developed by Konkan Railway [5].
The system consists of Loco ACD with a console (message display) for the driver (in each Loco Engine), Guard
ACD with remote (fitted in Guard Van), Station ACD with console (fitted in Station Masters' Cabin), Manned and
Unmanned Gates ACD with hooters and flashers (in each location) and Repeater ACDs (fitted at locations having
obstructions in radio communication such as hilly areas) which work in concert to prevent the following kinds of
collisions and accidents like-Head on collisions ,Rear end collisions ,Collisions due to derailment, Collisions at the
level crossing gates .
3. Technical detail of an anti-collision system:
It is impossible to entirely avoid situations that nobody has ever
thought of, but which could develop onto catastrophes. So for the safety purpose, anti collision system for railways
has been planned and developed. An Anti-Collision system developed for safety purpose consists of and uses the
following technologies like:
4. Simulation and modeling:
Traditionally circuit simulation has been a non –interactive affair. In the early days net list were prepared by hand,
and output considered of reams of numbers.
4 .1 Proteus Simulation Software:
Proteus Virtual System Modeling (VSM) combines mixed mode SPICE circuit simulation, animated components
and microprocessor models to facilitate co simulation of complete microcontroller based designs. For the first time
ever, it is possible to develop and test such designs before a physical prototype is constructed. This is possible
because one can interact with the design using on screen indicators such as LED and LCD displays and actuators
such as switches and buttons. The simulation takes place in real time (or near enough to it): a 300 MHz Pentium II
can simulate a basic 8051 system clocking at over 12MHz. Proteus VSM also provides extensive debugging
facilities including breakpoints, single stepping and variable display for both assembly code and high level language
source.
4.2Microcontroller Model functionality:
The core of any embedded system design is the microcontroller and the
completeness of the model as well as its accuracy are therefore of primary importance. It should always be ensured
that simulation models for microcontrollers not only support a peripheral that one wants to use but support the mode
in which one wants to use the peripheral and to a satisfactory level of detail.
5. Circuit Diagram description of an anti-collision system:
For this particular system it has been assumed that
1km is a minimum safest distance to maintain safety between two trains 8 km track separated by 1km zones (total
seven zones) as a block have been considered. Each zone contains load cell, (Please refer the data sheet for load cell
specification) placed under the track. The threshold of load cell is set to 6 tones. Whenever a train passes over the
load cell then the load cell crosses its threshold and it gives analog signal to the load cell processing unit.