Aiming at the problem that the corridor of hydropower station is crisscrossed and the space is narrow

making it difficult for the rail-mounted inspection robot to make a turn at the intersection

a bidirectional track-changing device is proposed to solve the track-switching problem of the inspection robot.The device is structurally independent and easy to replace

and integrates a robot track docking system

a motion control system and a network communication system.While enabling the robot to change tracks

the device can prevent the robot from falling off the track-changing device.The control cabin and the track-changing device are integrated into one unit

with the internal layered structure installed and sealed.A mathematical model of the device is built

and an active disturbance rejection controller based on this model is designed.A prototype of the track-changing device is built

and its docking accuracy and motion stability are tested.The results show that the mechanism has the ability of precise track docking and maintains balance during rotation

and its space utilization rate is improved compared to traditional layout.