This document describes an automated railway gate controller project that uses infrared transmitters and receivers to automatically open and close railway gates based on the presence of an approaching train. When the train approaches the first reference point, the gate closes, and when the train passes the second reference point, the gate opens. The system utilizes amplitude shift keying modulation at 434MHz and a baud rate of 4800bps. An AT89S8253 microcontroller controls an IR transmitter LED and receiver to open and close the gate motor as trains pass through. The system aims to eliminate human error at unmanned railway crossings and reduce accidents.

1. AUTOMATIZED RAILWAY GATE
CONTROLLER
Project Guide :

2.  The aim of this project is to automatize the railway crossings in
order to avoid accidents due to human negligence.
 To control the opening or closing of gate two reference points
are required to be fixed at either side of crossing. RF1 and RF2
are the two reference points at which actuation for closing and
opening of gate respectively are to be initiated. When the train
approaches RF1, the gate is closed and when train levels RF2,
gate is opened and vice-versa.

4.  This project utilizes two powerful IR transmitters and two receivers: one
pair of transmitter and receiver is fixed at up side (from where the train
comes) at a level higher than a human being in exact alignment and
similarly the other pair is fixed at down side of the train direction.
 When foreside receiver gets activated, the gate motor is turned on in one
direction and the gate is closed and stays closed until the train crosses the
gate and reaches aft side sensors. When aft side receiver gets activated
motor turns in opposite direction and gate opens and motor stops.
 The reference point settings depend on the following factors:
1. Minimum breaking distance.
2. Speed allowed on that particular track.
3. Road traffic density, so as to clear the traffic before actually the gate is
closed.

5.  Modulation used: ASK(Amplitude Shift Keying)
 ASK is a form of amplitude modulation that
represents digital data as variations in the amplitude of a
carrier wave.
 Also called On-Off keying.
 Carrier frequency: 434 MHz
 Baud Rate: 4800 bps

7.  Microcontroller used-
AT89S8253 – 8051
 2.7V to 5.5V Operating
Range
 32 Programmable bidirectional I/O Lines

8.  The transmitter is a simple
IR transmitting LED. The
transmitted rays are not
visible.
 The IR receiver is an
electronic
component
whose resistance decreases
with
increasing
IR
intensity. It is also called
as “Photo diode”

10. Block Diagram
Circuit Diagram

11.  The advantage of this system is that human error is
eliminated from the picture.
 The problem of accident risks at unmanned level
crossings is solved.
 Installation of this system will lead to accurate and
precise regulation of railway crossings.
 Financial burden on railways is reduced due to reduction
of manpower.

12. Automatic Railway Gate controller can be successfully implemented
using both wired and wireless techniques. This type of designs are
well suited in the field of communications. Based on this design we
can transmit any information in the form of pulses. Since it is a
demonstration part, the range of the transmitter is limited, the
limitation being the power transmitted by the transmitter and
antenna. However the range can be increased by increasing the
power radiating capacity of the transmitter.

13.  B. P. Lathi, Modern Digital and Analog Communication
Systems, Oxford University Press, 3rd edition, 1998.
 VSRD International Journal of Electrical, Electronics &
Communication Engineering.
 G. K. Mithal and Ravi Mittal, Radio Engineering,
Khanna Publishers, 17th edition, 1992
 D. Roy Chowdhury and Shail B. Jain, Linear Integrated
Circuits, New Age International Publishers.
 M.Morris Mano, Digital Design, Pearson Education,
3rd edition, 2007 and edition, 2003.
–
The
Free
Encyclopedia
http://en.wikipedia.org/wiki/Frequency_Modulation.
 Wikipedia
 http://www.alldatasheet.com.
 J. B. Gupta, Theory and Performance of Electrical
Machines, S. K. Kataria & Sons, 14th edition, 2005-06.
 http://www.datasheetcatalog.com

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