The invention relates to the technical field of industrial robots, in particular to an 
oil tank cleaning 
robot with a squirrel-cage structure. The 
oil tank cleaning 
robot comprises a stepped shaft, afirst bearing, a second bearing, a tray combination body, a driving device, a 
spur gear with a hub, a battery, a control panel, a driver, a 
flange, a conductive 
slip ring, a first end cover, a secondend cover, a battery charging head, a first connecting rod, a second connecting rod and an outer cylinder. According to the 
oil tank cleaning 
robot with the squirrel-cage structure, the driving deviceis composed of a stepping motor and a speed 
reducer, the starting and stopping control performance and reverse 
rotation control performance are good, the position precision and the 
repeatability of motion are good, the stepped shaft can be driven by the driving device, and therefore an executing mechanism can be directly driven to execute designated motion path, and the selection of parts of theexecuting mechanism is reduced to a certain extent; and the closed 
type metal structure design is adopted, the 
system is compact in structure and modularized, and therefore the oil tank cleaning robothas the advantages of being good in sealing performance, firmer and more durable, easy to clean and maintain, and capable of being used for a long time.