The application of the equipment inspection system based on the outdoor mobile robot used in the smart substation or automatic substation is described. With the video camera， thermal infrared imager， microphone and other sensors， the robot has realized optimal path planning and two-way movement based on the magnetic track to patrol devices by autonomous or remote control to detect thermal problems and abnormal appearances. By image processing and pattern recognition， this robot system can identify the opening/closing state of breaker and isolator. When executing device operation by remote control or sequence control， the mobile robot can replace operating people to check the state of a controlled device. By practical experience， this mobile robot provides an innovative means of detection and monitoring for the smart substation and unmanned substation.