AUTO Railway Crossing
In this project we control railway crossing system automatically. In this project we use total three control systems.
1. Pre station monitoring system
2. Auto open and close railway gate.
3. fish plate open indication.
4. Auto path indicator.
In pre station monitoring we will monitor station and display on second LCD when train is at other nearest station before that display. So we will try to use no of LCDs in this project on different stations .
1. Auto open and close railway gate . this provision is very important version also. By using this technique we not only save the valuable life of human being but provide a smart modification in railway automation. Opening and closing of this door is provide by the stepper motor logic. Here we use stepper motor for opening and closing the door automatically. When we use this option then we use magnetic reed sensor for this purpose. By using this technique when train sense the magnetic sensor then railway gate is automatic open and automatic closed. For opening and closing the door we use two reed sensor.
2. Auto indication of the fish plate indication. In this version we show that how we sense the fish plate broken indication. By using this technique when fish plate is open then red light is on and when fish plate is closed then green light is on.
3. Auto tracking the railway path indication. In this option we use different reed sensor to monitor the position of the railway station step by step.
In this project we use ic 89c51 as a main microcontroller for process all these operations. Pin no 40 of the ic is connected to the positive supply. Pin no 31 is also connected to the positive supply. Pin no 20 is connected to the negative supply. In this project we use total 10 reed sensor. Out of these 10 sensorís 8 sensor is connected to the auto path indication and 2 sensorís is for the auto opening and closing railway gate. Reed sensor is a magnetic sensor when reed sensor sense a magnetic field then it provide a signal to the microcontroller for the further operations. Port p1.0 to port p1.7 is connected to the all reed sensors. Port p1 provide only 8 pins for the operation so other two reed sensor is connected to the port p3.5 and port p3.6.
Positive supply . We provide a 5 volt regulated power supply for the pin no 40 and 31. For this 5 volt regulated power supply we use one step down transformer and full wave rectifier circuit. Output of the rectifier circuit is connected to the filter circuit. Output of the filter circuit is further converted into 5 volt dc with the help of the. 5 volt regulator circuit. Here we use ic 7805 as a regulator circuit. Output of this 7805 is completed 5 volt regulated. Pin no 20 of this ic is connected to the ground pin. All the reed sensorís pins are connected to the ground pin. All the pins of the microcontroller is high on default. When microcontroller is on then all the pins of the microcontroller is become high and due to that We always provide a low input from the sensor and always gets a low output as a output pins.
For display all the station one by one we use lcd as a output monitor device. In this project when Output of the Port p0 is connected to the data pins of the lcd. Here we use total eight data lines for the lcd. Addition with these data lines we use three enable pins for the lcd operation. These three pins are Enable
Enable pins is connected to the port p2.7 and R/S pin is connected to the p2.6 and R/W pin is connected to the p2.5 of the microcontroller. Supply voltage of the lcd is positive 5 volt and we provide a control and variable 5 volt to the contrast pin of the lcd to provide a brightness of the lcd.
Stepper motor is connected to the p2.3 to p2.0. Here we use stepper motor to open and close the door automatically with the help of the reed sensor. Microcontroller provide a negative output from this pins and when microcontroller provide a negative output then we inverter circuit to convert this negative output to positive with the help of ic 4049.
As per the logical diagram of the ic 4049 we show that how we use this ic as a inverter cum buffer .PIn no 3,5,7, 9, 11 ,14 is the input pins and pin no 2,4,6,10,12,15 is the out pins of this ic. Pin no1 is connected to the posiive supply and pin no 8 is connected to the negative supply
IC 2051 DETAIL:
LIGHT EMITTING DIODE
It is diode which emits visible light when it is energized. In all semiconductor PN junction diodes some of the energy is given off as heat and some in the form of photon. In silicon and germanium types the greater the percentage is given up in the form of emitted light, the heat generated becomes insignificant.
In other words, materials such as gallium arsenic phosphide ( GaAsP) or gallium phosphide ( Gap) , the numbers of photon of light energy emitted is sufficient to create visible light source.
The process of giving off light by applying an electric source of energy is called electroluminesce .Thus L.E.D. is a PN junction having a forward bias and characteristics similar to diodes. L.E.D. operate at voltage level of 1.7 volt to 3 volt by epoxy lens. The two electrodes are metal frame and the leads coming out of the enclosure from the outlet and inlet are for the voltage.
All the L.E.D. are highly monochromatic. Three colourís are commonly available : Red, Green, and yellow. Blue LEDíS also exists, but are expensive. LEDíS are widely used in displayís and as indicators. the shape of LED varies considerably, but the most common type is cylindrical, with a hemispherical end. The longer of the two leads is the anode, which must be connected to the positive voltage
A regulated voltage source is one in which the voltage is constant, and independent of the current flowing through the load from the voltage source. Although a Zener diode can be used to provide a regulated voltage, it is often more convenient to employ a voltage regulator device. These are integrated circuits on a silicon chip, inside a case having three leads. The performance of such voltage regulators is far superior to that of zener diodes, and they are commonly used in power supply circuits .In below figure we show the shape and pin numbering conventions. The metal tab, which has a hole, can be attached to a heat sink, or to the circuit board.
Type 78xx are positive voltage regulators, and 79xx are negative regulators. If the device is labelled 7805, the output voltage is 5VDC. If the number is 7912, then it means device is negative regulator and output is 12 VDC.
1. TRANSFORMER (9-0-9) 01
2. LCD(2*16) 01
3. IC 89C51 01
4. IC 4049(INVERTER) 01
5. DIODE 4007 06
8. STEPPER MOTOR 01
9. LED RED 05
LED GREEN 01
10. PRESET 4K7 01
11. REED SENSOR 10
12. CRYSTAL OSC(12 MHZ) 01
13. TRANSISTOR 1061 04
ō 8051 programmer universal kit
ō CRO 20 Mhz
ō Digital multimeter
ō Keil for Programming
ō OrCAD for PCB designing
ō Proteus 7.6 Simulation
2. Easy to fabricate
4. Low cost
1. Cost increase with in crease in cost.
2. No reliable manufacturer in India
ō 8051 Microcontroller and Embedded Systems by
Mohammad Ali Mazidi