Mobile robots are becoming increasingly necessary to execute tasks related to the inspection of critical infrastructures such as Power-stations, Substations, Semi-conductor manufacturing etc. They can maneuver in complex work-spaces that are otherwise difficult or dangerous for a human operator. We have developed an autonomous Substation-inspection mobile Robot (SIR) for the inspection of power substations. The robot is equipped with sensors such as PTZ cameras, IR thermal sensors, LIDAR etc. along with a path-following navigation platform to perform regular inspection for damages in circuits and transformers. The robot utilizes advanced vision processing and machine learning algorithms for system identification and monitoring.