As reported in an article by the New York Times, Google and Tesla are working on self-driving cars using radically different approaches. Google is using the “elevator” metaphor, while Tesla is using the “plane autopilot” metaphor. IEEE Spectrum, the journal of the Institute of Electrical and Electronics Engineers, published an interesting analysis of the approaches taken by different companies.
As you can gather from from this interesting Planet Money podcast, Google has decided that their autonomous vehicles will be much like elevators: you push a button, and the car (like an elevator) drives to the intended destination, without possible intervention from the driver.
The alternative approach, followed by Tesla and other car manufacturers, is the autopilot metaphor. The autopilot in a plane can be programmed to take the plane to a specific location, but the pilot can take back control of the plane at any moment. The autopilot assists, but does not replace, the pilot.
A number of experiments conducted by Google led the company to believe that it would be very risky to bet on the possibility that drivers would be able to take back control of the vehicle, in an emergency. Google found out that many drivers were not paying attention to the road while the autopilot was in charge and, instead, they would be working on their computers, talking on the phone or even taking a nap. Based on this data, Google designed cars without brake pedals, steering wheels or accelerators. These cars may seem strange to us today, just as elevators seemed strange in the beginning, when elevator operators were discontinued, and users started operating the elevators themselves.
The recent accident with a Tesla gives some additional evidence that the “plane autopilot” model may create additional risks, since drivers will not, in general, be alert enough to avoid accidents when the autopilot fails. Additionally, human drivers may become the highest risk in a world where most cars are driven by computers, given the inherent unpredictability of human drivers.
Only the future will tell whether future cars will be more like elevators or like planes, in what respects their self-driving ability.