1. A control system comprising: one or more processors; a non-transitory computer readable medium; and program instructions stored on the non-transitory computer readable medium and executable by the one or more processors to: receive sensor data that indicates topographical features of an environment in which a robot is operating, wherein the robot has a torso; determine, for a particular topographical feature of the environment in a direction of travel of the robot, a height of the particular topographical feature and a distance between the robot and the particular topographical feature; estimate a ground plane extending from the robot in the direction of travel toward the particular topographical feature, the ground plane fitting to the determined distance and height; determine a grade of the estimated ground plane; and control actuators of the robot so as to cause the robot to pitch the torso based on the grade of the estimated ground plane.