A center of gravity of a mobile cleaning robot may be positioned on an imaginary central longitudinal axis of the mobile robot. The center of gravity of the mobile robot may be positioned at a front side of an imaginary central horizontal line connecting spin rotation axes of left and right spin mops of the mobile robot. The center of gravity of the mobile robot may also be positioned at a front side of a center of gravity of a battery and a center of gravity of a water tank, and at a rear side of a center of gravity of a sweep module of the mobile robot.