The invention relates to a motorized robot for cleaning swimming pools, including: means (2) for moving the robot, having a surface (3) for making contact with a movement surface submerged in the swimming pool; means (4) for generating a circulation of fluid in the robot, including an opening for the suction (5) of said fluid, and an opening for the backflow (6) of the aspirated fluid; a conduit (7) of fluid connecting the suction and backflow openings; means for generating (8) a flow of said fluid in the conduit; a strut for lifting at least part of the contact surface (3) from the movement surface, said strut being mobile between a first inactive position in which the strut is retracted inside the robot and a second active position in which the strut projects past the contact surface of the movement means in such a way that part of said contact surface can no longer be in contact with the movement surface; and means for controlling (10) the movement of the strut between its active and inactive positions, said means being activated by a movement of the fluid in the fluid conduit, and including means (11) for opposing the movement of the fluid in the fluid conduit (7), which are mobile in said conduit in such a way as to at least partially block the conduit or release it, and connected to the strut in such a way that the strut takes on its active or inactive position according to the position adopted in the fluid conduit by the opposition means.