If the rover is moving at a constant speed, then there is no net force acting on it and the rover is in equilibrium. In particular, Newton's second law says that
n + (-w) = 0 → n = w
where n and w denote the magnitude of the normal force acting on the rover and its weight, respectively.
With a gravitational acceleration of 1.6 m/s², the rover's weight, and hence the magnitude of the normal force, is
w = n = (1100 kg) (1.6 m/s²) = 1760 N