Honeywell executives, who haven't previously discussed the project publicly, say the system uses onboard computers and navigation devices to automatically control aircraft movements on the ground.

WSJ: Honeywell Tests Autopilots for the Tarmac

This system, Positive Train Control (PTC), is intended to stop or slow a train automatically if a driver goes too fast or passes a red signal.

ECONOMIST: American railways

Mercedes-Benz's Distronic Plus system, for instance, contains radar-based sensors as part of its cruise-control system, to keep the car at a preset distance from the vehicle in front, braking automatically if the gap narrows quickly.

ECONOMIST: Rational consumer