This locomotion device includes a mechanism suitable for converting the pivoting of a roller into a movement of a pad to an advanced position in which it brakes this roller, this mechanism includes a planetary gear set having: a planetary wheel attached to a sole and the axis of revolution of which coincides with a pivoting axis of the roller and a satellite gear rotated by the planetary wheel about an axis of revolution attached without any degree of freedom to the roller and a pin movable by the satellite gear between: a near position in which it pushes and maintains the pad in an advanced position and a distant position in which it allows the movement of the pad from its advanced position to a retracted position.