This system consists of photodiode, microcontroller and motor circuit. The main aim of the system is to sense the output of photodiode from onboard IR sensor as soon as the crack is detected on rail track . So with help of infrared module, this will capture the instantaneous detection time & number of that respective crack, which can send to show on LCD display screen. The detection time is used to calculate the distance for particular crack by knowing the speed of moving robot. The supply is given to crack detection block, microcontroller & motor driver IC L293D through power supply block. Microcontroller block is interfaced to motor driver & LCD display block, while it takes inputs from crack detection circuit. Crack detection circuit consists of LED-Photodiode Assembly. This LED- Photodiode assembly detects crack and send signal to AT89S52 Microcontroller. The IR Sensor-general purpose proximity sensor We use it for collision detection. The module consists of an IR emitter and IR receiver pair. The high precision IR receiver always detects an IR signal. The module consists of 358 comparator IC. The output of sensor is high whenever it IR frequency and low otherwise. The on-board LED indicator helps user to check status of the sensor without using any additional hardware. The power consumption of this module is low. It gives a digital output. The sensitivity of the IR Sensor is tuned using the potentiometer. The potentiometer is tuneable in both the directions. Initially tune the potentiometer in clockwise direction such that the Indicator LED starts glowing. Once that is achieved, turn the potentiometer just enough in anticlockwise direction to turn off the Indicator LED..... etc i am trying to make a railway track crack detection system...how can i make this?