My questions about driverless cars
We have the past few years seen a steady stream of articles about the inevitable arrival of driverless cars. I am skeptical, but willing to be persuaded. I have questions about how this would work. The articles I have seen don’t address, or even imagine, them. Perhaps this is a failure of journalists to ask the right questions. Most of the articles seem to fall into two categories: paraphrases of industry press releases, or Gosh! Wow! pieces by writers who have been thoroughly seduced. So take this post as a critique of journalism as much as it is about driverless cars.
There are two scenarios for driverless cars: completely autonomous with no input from the rider apart from designating the destination, and semi-autonomous cars that hand off control to a human as necessary. The fully autonomous version is far sexier, of course, and most of my questions are about that version.
But first a question about the semi-autonomous version: How does the hand-off work? The thing is, a driverless car is very attractive to those of us with a daily commute, but only if this means we can use the time doing other stuff, e.g. sleep, read, copulate, and so forth. The problem I see with the hand-off of control to the human is that a driver has to be oriented to the surroundings: road conditions, traffic, where exactly they are, and so forth. This orienting is continuous and automatic when driving. It is anything but, when sleeping, reading, or copulating. This need not be a problem with a planned hand-off. If, for example, the car is autonomous on a freeway but human-controlled on surface streets, then an alarm could sound a few minutes before the car reaches the off ramp. But I see ample potential for wackiness with unplanned, much less emergency, transitions. How much situational awareness do I have to maintain during the trip? If I have to pay constant attention to the trip, prepared to take over on short notice, then frankly that sounds agonizing. I would rather just drive.
Next I move on to fully autonomous cars. By way of background, I have a commute of about 35 miles through secondary roads. These vary from residential streets to country roads through woods and corn fields. They are perfectly good roads, mostly with one lane in either direction, most of the way with a solid double yellow line dividing the two directions.
Articles about driverless cars routinely include the pious statement that the car will of course follow traffic laws. People who question this mostly wonder if this really means the car will putter along when everyone else, including the cops, are driving ten to fifteen over the posted limit. My questions are different. I wonder about that double yellow line. Its whole point is that you aren’t allowed to cross over it, expect for left turns. So here are bog-standard routine situations in my daily commute:
(1) It is trash day. I end up behind a trash truck stopping every few feet. Present-day, this is a minor annoyance. In practice I ease over so I can see around the truck, and zoom across that double yellow line as the truck is stopped, and in a spot where I can see that there is no immediately oncoming traffic. The trash guys around here are pretty cool. Sometimes they’ll even signal me whether or not it is safe to pass. Everyone does this, including the cops and including the guys immediately ahead of a cop car. But this maneuver is technically illegal. So in our driverless future, are we going to stop and start for miles on end behind that trash truck?
(2) It is trash day. The trash truck is come and gone, and an empty trash can has rolled/been tossed/been blown all or part way into the roadway. In the real world, this hardly rises to the level of petty annoyance. If there is no oncoming traffic, I swerve around it without slowing. If there is oncoming traffic, I slow to await a gap, and in the worst case I come to a complete stop. At that point I might nudge the can off the road, or in a pinch get out of the car and move it, but in practice this is virtually never necessary. What does a driverless car do?
(3) There is an accident up ahead. Emergency personnel are on the scene, and the police are directing traffic away. There is a police car sideways in the middle of the road, and the policeman is waving cars to turn around. So far so good. I am confident that our driverless car and recognize the obstacle and avoid running the officer down. But how does it recognize and properly interpret the cop’s instructions, rather than (e.g.) treating the police car as a minor obstacle to go around, kind of like a trash can? There also is that pesky double line again. The cop is instructing traffic to make a technically illegal U-Turn. So what does the car do?
Moving on, in some of the articles I see a passing mention that the system doesn’t work in inclement weather. Please. This not only isn’t ready for prime time, it isn’t ready for the late-night infomercial block. Get back to me when you can navigate a road with three feet on snow on either shoulder and the lane markings obscured by salt and/or slush.
Come to think of it, we see mentions of how the Google car relies on 3D mapping down to within centimeters. Please. In winter in snow country the effective driving environment changes from hour to hour. Mountain View may be the center of the universe, but it isn’t the entirety.
Finally, I want to ask about failure modes. Whenever I mention this, people think I mean crashes and they respond with a discussion about how many happen with human drivers. That’s not what I mean. What I am asking about is more mundane stuff like flat tires. Currently, if your tire goes flat while driving you do a rapid situational analysis to figure out how to respond. If you are next to a nice wide shoulder you respond one way. If you are on a bridge with no shoulder you respond differently. You might respond yet differently if that bridge is one of those long ones with “Bay” in its name. What does an autonomous car do?
More broadly, when you drive your car every day you know how it should feel. If the brakes don’t feel quite right, it is time to have them looked at. Or maybe there is a vibration it didn’t have before. And so on. How does this work with our automated car? If you own it and ride it daily you might pick up on this stuff, but then again you might not, what with your sleeping and reading and copulating the trip away. How do you feel the brakes are a little off, when you aren’t applying them yourself? I have this sneaking suspicion that there is a tacit assumption that all these automated cars will be no more than three years old, and fanatically maintained. I see vast potential for wackiness when this assumption hits the real world.
I’m sure I could come up with more questions, and I would be fascinated to see yours. It may well be that they can all be answered satisfactorily. But color me skeptical until they are.