How to make sure that everything is in order with the 27-km Large Hadron Collider (LHC) and the experiments are not threatened with failures or errors? Of course, there is a constant computer diagnostics, but an external examination of the world’s largest particle accelerator is required. Today, this responsibility is assigned to two autonomous robots called TIM (Train Inspection Monorail). Moving at a speed of 6 km / h on a monorail mounted on the ceiling, mechanical inspectors monitor the structure of the tunnel in real time, measure the level of radiation, temperature, oxygen content in the air, as well as the bandwidth of the communication channel. Robots suspended from the ceiling carry out visual and infrared observation, and if necessary they can drag a trailer with the materials necessary for a particular section of the LHC. TIM patrols leave on command of a human operator, and until that moment they are placed in additional tunnels. Note that during the time of the Large Electron-Positron Collider, which occupied the same tunnel until 2000, people were inspecting, but during the construction of the LHC, scientists decided to replace a person with a special automated robot for convenience.