An autonomous robot for crack detection in railway track
Cracks in railway tracks have resulted in several train accidents involving huge loss of human lives in many developing countries including Nigeria. Railway transport is vitally important for the economic and industrial development of any nation. In order to make this means of transportation safer in Nigeria, manual methods are currently been used to check for cracks on railway tracks. These manual methods are tedious and timeconsuming. And sometimes with the manual methods, cracks may go unnoticed, thereby, resulting in accidents. In order to overcome this shortcoming which has resulted in tragic but avoidable accidents, this research was conceived. The autonomous robotic vehicle designed in this project uses an ATMEGA 328 Microcontroller on board arduino, a light emitting diode (LED)/light dependent resistor (LDR) assembly, a bluetooth module, servo and DC geared motors and a lithium battery power supply. In this design, the LED was attached to one side of the rails and the LDR to the opposite side. The principle of operation is such that, during normal operation when there are no cracks, the LED light does not fall on the LDR and hence the LDR resistance is high. However, when the LED light falls on the LDR, the resistance of the LDR gets reduced and the drop in resistance will be approximately proportional to the intensity of the incident light. This change in resistance indicates the presence of a crack or some other similar structural defect on the rail track. Two unique features in this design include, the use of the differential drive method in the control of the robotic vehicle because it's a 2 wheeled vehicle compared to other popular designs; and the introduction of a mobile app (not common with any existing system) which can be used to remotely control the movement of the vehicle.