Why Driverless Technology In Cars Isn’t The Same As Autopilot Systems In Planes
One of the more interesting and exciting developments in the world of automotive technology these days is all the research into autonomous cars (aka driverless cars or self-driving cars). They’re really trying hard to develop these and get them working. In fact, one recent news report claimed that Volvo is looking for 100 volunteers from the industry’s home town of Gothenburg to commute to work for a year in prototype driverless cars – along a selected route that don’t have bikes, pedestrians or snow. That last factor might be a bit of a challenge in Sweden: Gothenburg may have a warm climate compared to the rest of Sweden but still gets an average of 10 snowy days per month during December and January, snowfalls possible from November to April, and had a record number of snowy days in 2016.
The drive (ha ha) behind driverless cars is to eliminate one of the main causes of accidents: human error. Humans make dumb decisions, forget the road code, have attention that wanders or gets distracted, get tired and get frazzled. Humans also like drinking alcohol. Computers don’t get drunk, etc. so the thinking is that if you can get a computer to take over a lot of the decision-making with a system that can calculate distances and speeds precisely, never forgets the highway code, doesn’t get tired and doesn’t start planning dinner in the middle of the commute. Therefore, a car that uses automated systems will be safer, as the human error is eliminated.
The standard comparison is to autopilot systems in planes, which have been in use for quite some time.
The Road Isn’t The Sky
OK, let’s just stop and think about that. Although autopilot systems have been standard in most passenger aircraft since at least the 1930s (using an analogue system rather than computerised), the main idea in autopilot systems is, according to the FAA, designed to “significantly reduce workload during critical phases of flight”, not eliminate the workload of the pilot altogether. It can be turned on and off as the pilot wishes, kind of like cruise control. The big fat FAA manual for general aviation (that’s the basic flying licence level) contains guidelines on when NOT to use autopilot. Planes with autopilot function are not “pilotless planes”. Yes, drones exist, but they’re usually kept for missions you don’t want to send people on. If a drone crashes, that’s annoying. If a plane crashes with people on board… you get the picture.
What’s more, the air isn’t as busy a place as the road. Go to even the world’s busiest airport (Hartsfield–Jackson Atlanta International Airport in Atlanta, Georgia, USA) and you’ll see an average of about 2.4 thousand aircraft movements (takeoffs and landings) per day. The world’s busiest road (Ontario Highway 41 in Ontario, Canada) sees 500,000 vehicles per day go through on average. Do a simple test if you’ve got a spare day (don’t we all wish!) and pick an intersection near an airport. Count the planes going in and out, and count the number of vehicles going through the intersection, and you’re guaranteed to count more cars than planes, unless you’ve selected a tiny little airstrip in the Outback.
The sky also doesn’t have the equivalent of intersections. The closest pilots get to an intersection would be an airport. During takeoffs and landings, the pilot (and probably the co-pilot) is on full alert. What’s more, the issues to do with who gives way to whom and when the pilot can enter the “intersection” is handled by the ATC (air traffic controller), who has probably been in radio contact with all pilots approaching the airport and has had received all the flight plans about what’s going to land and take off earlier in the day. This does not happen at your nearest roundabout or traffic lights.
Driving a car also requires negotiating more intersections. In a plane, the pilot sets the autopilot function to navigate and steer, and the plane can go in a straight line, more or less, to where the pilot wants to go. This doesn’t involve turning left in 200 metres, then taking the second intersection to the right, then along the one-way system until the next set of lights and turning left, then carrying on to the roundabout and… well, you get the picture. This means that there’s less for the autopilot to do: it will make sure the heading is right, use gyroscopes to correct for any imbalances and get the attitude and altitude right.
Admittedly, there are more things that a plane’s autopilot function has to take care of, thanks to things like stall speed (go too slow and the plane will fall out of the sky), yaw, pitch, roll and thrust. The autopilot also handles some navigation issues via GPS and checks the altitude. However, these are mostly issues that are internal to the plane. Taking care of external things, such as coping with changing winds and weather, is the job of the pilot. In a vehicle, we’ve already got electronic stability control packages and nobody thinks of those in discussions of driverless cars. However, what a driverless car would need to handle is mostly external to the car: oncoming vehicles and the like.
Our roads contain pedestrians, bikes and animals. These are not governed by computer algorithms and will do things that autonomous technology can’t predict. Detect, yes. Slow down for, yes. Predict, no. This is also a problem for pilots and is one that autopilot can’t do much about. Not that there are bikes and people whizzing about up in the flight paths but there are birds. Bird strikes are some of the major hazards of flying – if you remember about 10 years ago with that incident of a big passenger plane having to do an emergency landing in New York’s Hudson River, it was a collision with a goose that made things go to custard.
Pilots have to stay alert when flying. No pilot relies entirely on the autopilot all the time – just some of the time. The pilot is always responsible for what happens. In addition, on longer flights, there is a second person or even a third ready to take over responsibility if the pilot has been on alert for too long. Pilots are in radio contact with other pilots along the route, plus the control tower(s), so everybody knows where everybody else is. It’s not the same on the road.
So what’s the moral of all this? In my opinion, our image of sitting back playing Angry Birds and sipping a latte while the vehicle takes us from our homes to work has to go when we think of driverless cars. Even if the car has good enough sensors and navigation to get you around that corner at the right speed, and can remember the give way rules for you and gun into a gap at the roundabout, the driver will still have to be on the alert to take over if things don’t quite go to plan or if the unexpected happens. Autonomous systems should be there to help and back up the driver and reduce workload, not take over from the driver completely. If you want the Angry-Birds-and-latte experience, take the bus or carpool so you get your turn at being the passenger.