automatic anti collision railway system using embedded system

Automatic anti collision railway System Using

Embedded System

Aim:

To Prevent Accidents for Trains using an intelligent device with

ultrasonic sensor.

Need:

It is necessary to have an intelligent system which identifies the

accident before it happens and informs the driver to be alert or to regulate

the speed of the vehicle (say train) and to stop it, if it is very close to the

collision.

Working of the Project:

This project is implemented by connecting Ultrasonic Sensors in front

of the train. The Ultrasonic sensors will give the distance between the

present train and the train which is coming in the opposite direction. The

distance is constantly monitored by a microcontroller and when the distance

is close, it is programmed to regulate the speed and also to stop the train if it

is necessary.

For project demonstration we have implemented a small model with a

single sensor fixed in it. The same operation is done for all the trains.89 RANGARAJAPURAM MAIN ROAD,KODAMBAKKAM,CHENNAI-24

PL VISIT www.maastechindia.com,mobile:098402 34766

This is diagramatically shown below:

Parameter Monitoring :

Since our project is related to the vehicles, in addition to the

mentioned aim we can also monitor the temperature of the Vehicle. The

89 RANGARAJAPURAM MAIN ROAD,KODAMBAKKAM,CHENNAI-24PL VISIT www.maastechindia.com,mobile:098402 34766

Model Top View (Real model)

Ultrasonic Sensor

Model (assumption)

engine temperature is measured by using the thermistor which is connected

to an ADC of PIC Microcontroller.

Block Diagram


Thermistor

Potential Divider

PIC MicrocontrollerPIC16F877 Distance Input (Ultrasonic)

Stepper Driverand Opto Coupler

Stepper Motor

Power Supply +5VDC

Stepper Power Supply +12VDC

Block Diagram Explanation

Power Supply:

Used to power the PIC Microcontroller. This is generated from the

incoming AC supply of 230V.

Stepper Power Supply:

Used to run the Stepper Motor. This is generated from the incoming

AC supply of 230V.

Stepper Driver and Optocoupler:

The TTL Level Pulse signal from the controller is not sufficient to run

the stepper motor as it requires the current of 1.2 amps. So the signals from

the controller are buffered and isolated and amplified using transistors. Then

the amplified voltage is applied to the stepper motor. The stepper driver

board does this job.

Ultrasonic Sensors:

This ultrasonic sensors are used to measure the distance between the

current train and the opposite train. The ultrasonic sensor has a transmitter

and receiver placed side by side. The ultrasonic sound waves are transmitted,

and if there is any obstacle, the waves are reflected back and it is sensed by

the receiver. The unit then calculates the travel time of the wave and

converts it into distance.


Thermistor and Potential divider:

It is a transducer which is used to measure the temperature of engine. The

resistance of the device varies according to the atmospheric temperature.

The resistance variation from the thermistor is converted into its

corresponding voltage variation using this voltage divider circuit.

LCD Display:

A 16X2 row LCD Display is used to display the parameters sensed and the

events happening.

PIC Microcontroller:

The PIC 16F877 Microcontroller is used to process the inputs from

the ultrasonic sensor and it reduces the speed of the train or stops the train.

It also senses the temperature and displays it in the LCD display. All this

process are controlled by the embedded C program which is written and

stored into the controllers memory. The microcontroller features are given

below.

Core Features:• High performance RISC CPU• Only 35 single word instructions to learn• All single cycle instructions except for program branches which are of two cycles• Operating speed: DC - 20 MHz clock input DC - 200 ns instruction cycle• Up to 8K x 14 words of FLASH Program Memory, Up to 368 x 8 bytes of Data Memory (RAM)• Interrupt capability (up to 14 sources)• Direct, indirect and relative addressing modes• Power-on Reset (POR)


• Power-up Timer (PWRT) and Oscillator Start-up Timer (OST)• Processor read/write access to program memory• Wide operating voltage range: 2.0V to 5.5V• Low-power consumption: - < 0.6 mA typical @ 3V, 4 MHz

- < 1 µA typical standby current

Peripheral Features:

• Timer0: 8-bit timer/counter with 8-bit prescaler• Timer1: 16-bit timer/counter with prescaler, can be incremented during SLEEP • Timer2: 8-bit timer/counter with 8-bit period register, prescaler and postscaler• 10-bit multi-channel Analog-to-Digital converter• Synchronous Serial Port (SSP) with SPI (Master mode) and 12C(Master/Slave)• Universal Synchronous Asynchronous Receiver Transmitter (USART/SCI) with 9-bit address detection• Parallel Slave Port (PSP) 8-bits wide, with external RD, WR and CS

Conclusion and future enhancements:

In this project we have used ultrasonic sensors for detecting the

opposite train. This distance can be increased by putting long range

ultrasonic level sensors. We can also incorporate a GPS and GSM Modules

for preventing train accidents. The GPS Lets us to know the present location

and GSM Sends it to another train. Thus if the two trains are at the same

location then the train is immediately stopped.


automatic anti collision railway system using embedded system

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