In contrast, a human driver has very acute sensors: eyes for seeing
things and ranging distances, force sensors to sense acceleration, and
balance to sense levelness. A human expects certain things of an auto-
mobile’s (car, truck, jeep, HumVee, etc.) mobility system (wheels, sus-
pension, and steering) and uses those many and powerful sensors to
guide that mobility system’s efforts to traverse difficult terrain. The
robot’s mobility system must be passively very capable, the car’s mobil-
ity system must feel right to a human....