30-03-2011, 03:52 PM
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AUTOMATIC RAIL automationWAY GATE CONTROLUSING MICROCONTROLLER
ABSTRACT: In the rapidly flourishing country like ours, accidents in the unmanned level crossings are increasing day by day. No fruitful steps have been taken so far in these areas. Our paper deals with automatic railway gate operation (i.e.) implemented in unmanned level crossings at remote areas. Detection of train approaching the gate can be sensed by means of four sensors placed on either side of the gate. Train arrival and departure sensing can be achieved by means of Relay techniques. When the wheels of the train moves over, both tracks are shorted to ground and this acts as a signal to microcontroller (89C51) indicating train arrival. RED signal appears for the road user, once the train cuts the relay sensor placed before the 5Kms before the gate .A buzzer is made on as a pre cautionary measure for the road users. Once micro controller senses that there are no vehicles inside, it automatically produces signal to operate motor through relay circuit and hence close the gate for passage of train. This can be implemented in manned level crossings also, as manual errors can be eliminated by automation .
INTRODUCTION: At present scenario, in level crossings, the railway gate is operated normally by a gate keeper after receiving the information about the train's arrival. When a train starts to leave a station, station master of the particular station delivers the information to the near by gate. The above said procedures are followed for operating the railway gates. Semiautomatic railway gate operation is also followed in certain areas. Signals are located in the vicinity of the railway gate along with gate master board and a marker light. Our paper deals with automatic railway gate control (i.e.) gate operated with out gate keepers. It is implemented in unmanned level crossings at remote areas.SCHEMATIC DIAGRAM:.
The arrival of the train to reach the level crossing is sensed by the sensor R1/R2 placed on either side of the gate at about 5 km from the level crossing. So the arrival is sensed by the either side of the sensor and then the sensed signal is sent to the microcontroller. First we are calculating the velocity of the train by using IR sensor fixed in particular distance. Two set of IR sensors are placed before the gate. When the first set of IR sensor is interrupted we have to start the times and second set of IR sensor is interrupted we have to stop the times. By calculating this time we have to find the velocity of train using formula
V= distance/time So we are find out when the train will reach the gate, then signal use given to the motor to close gate. Before closing of gate, buzzer indication is given to the load user. A light signal is also placed additionally on either side of the gate and the addition warning to the load user indicating the closure of the gates. The departure of the train is detected by sensors R3/R4 which is about a km from the gate Infra red transmitter sensor gives the infra red rays, this wavelength depends upon the input frequency of the sensor. If frequency is high, wavelength is high .IR receiver sensor resistance depends upon the receiving IR signal. if receiver receives signal from transmitter, the resistance of the resistor will be low .If receiver does not get signal from the transmitter, its resistance will be high .so we get some voltage drop across the receiver depends on the resistance of the receiver. Comparator compares the signal given to the inverting and non inverting terminal ,it will give output in terms of saturation level .if inverting terminal input is high ,then comparator output will be at negative saturation(-12v).if noninverting terminal input ,comparator output saturation is positive(+12v).one input of comparator is from IR sensor and other input is reference signal . So we have to convert +12v to -12v pulse into TTL logic (0&5 ).
BLOCK DIAGRAM-TRANSMITTER:. The signal about the departure of the train is send to the microcontroller which operates the motor and opens the gate across the level crossing .
OPERATION: Output from IR section is fed to FM transmitter. In FM transmitter ,reactance modulator operates on tank circuit of LC oscillator .it is isolated from the buffer ,whose output goes through an amplitude limiter to power amplification by power amplifier .a fraction of output is taken from limiter and is fed to a mixer ,which also receives signal from crystal oscillator resulting from different signal ,which has the frequency usually about one twentieth of the master oscillator frequency ,is amplified and fed to phase discriminator. Its output is connected to reactance modulator and provides DC voltage to correct it automatically any drift in average frequency of master oscillator.
RECEIVER:
RF amplifier is always used in FM receiver. Its main purpose is to reduce noise figure, which could otherwise be a problem because of large bandwidth needed for FM .RF section tunable circuit is connected to antenna terminals. It is there to select the wanted frequency and reject all other unwanted frequencies. An amplifier output is fed to the mixer at whose input at another tunable circuit is present. The mixer is the non linear device having two sets of input terminals and one set of output terminals nonlinear circuit will have several frequencies in its output, including the difference between the two input frequencies. The difference frequency here is the IF and is the one to which output circuit of the mixer is tuned.The limiter is inform of clipping devices ,a circuit output tends to remain constant despite changes in the input signal .output from the receiver is fed to microcontroller.
AUTOMATIC RAIL automationWAY GATE CONTROLUSING MICROCONTROLLER
ABSTRACT: In the rapidly flourishing country like ours, accidents in the unmanned level crossings are increasing day by day. No fruitful steps have been taken so far in these areas. Our paper deals with automatic railway gate operation (i.e.) implemented in unmanned level crossings at remote areas. Detection of train approaching the gate can be sensed by means of four sensors placed on either side of the gate. Train arrival and departure sensing can be achieved by means of Relay techniques. When the wheels of the train moves over, both tracks are shorted to ground and this acts as a signal to microcontroller (89C51) indicating train arrival. RED signal appears for the road user, once the train cuts the relay sensor placed before the 5Kms before the gate .A buzzer is made on as a pre cautionary measure for the road users. Once micro controller senses that there are no vehicles inside, it automatically produces signal to operate motor through relay circuit and hence close the gate for passage of train. This can be implemented in manned level crossings also, as manual errors can be eliminated by automation .
INTRODUCTION: At present scenario, in level crossings, the railway gate is operated normally by a gate keeper after receiving the information about the train's arrival. When a train starts to leave a station, station master of the particular station delivers the information to the near by gate. The above said procedures are followed for operating the railway gates. Semiautomatic railway gate operation is also followed in certain areas. Signals are located in the vicinity of the railway gate along with gate master board and a marker light. Our paper deals with automatic railway gate control (i.e.) gate operated with out gate keepers. It is implemented in unmanned level crossings at remote areas.SCHEMATIC DIAGRAM:.
The arrival of the train to reach the level crossing is sensed by the sensor R1/R2 placed on either side of the gate at about 5 km from the level crossing. So the arrival is sensed by the either side of the sensor and then the sensed signal is sent to the microcontroller. First we are calculating the velocity of the train by using IR sensor fixed in particular distance. Two set of IR sensors are placed before the gate. When the first set of IR sensor is interrupted we have to start the times and second set of IR sensor is interrupted we have to stop the times. By calculating this time we have to find the velocity of train using formula
V= distance/time So we are find out when the train will reach the gate, then signal use given to the motor to close gate. Before closing of gate, buzzer indication is given to the load user. A light signal is also placed additionally on either side of the gate and the addition warning to the load user indicating the closure of the gates. The departure of the train is detected by sensors R3/R4 which is about a km from the gate Infra red transmitter sensor gives the infra red rays, this wavelength depends upon the input frequency of the sensor. If frequency is high, wavelength is high .IR receiver sensor resistance depends upon the receiving IR signal. if receiver receives signal from transmitter, the resistance of the resistor will be low .If receiver does not get signal from the transmitter, its resistance will be high .so we get some voltage drop across the receiver depends on the resistance of the receiver. Comparator compares the signal given to the inverting and non inverting terminal ,it will give output in terms of saturation level .if inverting terminal input is high ,then comparator output will be at negative saturation(-12v).if noninverting terminal input ,comparator output saturation is positive(+12v).one input of comparator is from IR sensor and other input is reference signal . So we have to convert +12v to -12v pulse into TTL logic (0&5 ).
BLOCK DIAGRAM-TRANSMITTER:. The signal about the departure of the train is send to the microcontroller which operates the motor and opens the gate across the level crossing .
OPERATION: Output from IR section is fed to FM transmitter. In FM transmitter ,reactance modulator operates on tank circuit of LC oscillator .it is isolated from the buffer ,whose output goes through an amplitude limiter to power amplification by power amplifier .a fraction of output is taken from limiter and is fed to a mixer ,which also receives signal from crystal oscillator resulting from different signal ,which has the frequency usually about one twentieth of the master oscillator frequency ,is amplified and fed to phase discriminator. Its output is connected to reactance modulator and provides DC voltage to correct it automatically any drift in average frequency of master oscillator.
RECEIVER:
RF amplifier is always used in FM receiver. Its main purpose is to reduce noise figure, which could otherwise be a problem because of large bandwidth needed for FM .RF section tunable circuit is connected to antenna terminals. It is there to select the wanted frequency and reject all other unwanted frequencies. An amplifier output is fed to the mixer at whose input at another tunable circuit is present. The mixer is the non linear device having two sets of input terminals and one set of output terminals nonlinear circuit will have several frequencies in its output, including the difference between the two input frequencies. The difference frequency here is the IF and is the one to which output circuit of the mixer is tuned.The limiter is inform of clipping devices ,a circuit output tends to remain constant despite changes in the input signal .output from the receiver is fed to microcontroller.
