Robot for machining a part of structure under water

A robot for machining a part of structure under water, comprising:

• a machine tool having a submersible motor, a machining element coupled to the motor, a chamber receiving a driven portion of the machining element, and at least one gas inlet communicating with the chamber;
• a support and guiding structure for the machine tool, fixable with respect to the part to be machined and having submersible mobile elements and corresponding submersible guiding elements defining axes along which the mobile elements are movable for positioning the machine tool with respect to the part to be machined, the machine tool being attached to one of the mobile elements within reach of the part to be machined when the support and guiding structure is fixed with respect to the part to be machined, the mobile elements and the guiding elements having a rigidity resisting to stresses produced by the machine tool when the machine tool is in operation;
• displacement units for displacement of the mobile elements along the axes;
• a gas supply connectable to the at least one gas inlet of the machine tool for injecting gas in the chamber;
• and
• a control unit connecting to the machine tool and to the displacement units, the control unit being programmable for operating the displacement units and the machine tool based on a closed-loop control mode in order to perform the machining of the part.