We’re over-relying on our cars' autopilot systems - a recent drive in a Tesla proved it

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I called up my buddy “Bob” this week and asked to go for a drive in his Tesla Model S. Bob isn’t his real name, for reasons you’ll soon understand.

Bob is very proud of his Tesla. “I’ve drunk the Tesla Kool-Aid,” he says every time I see him. I wanted to drive it after hearing of the news story last week from Alberta, where a young couple was charged with driving at 150 km/h while their seats were allegedly fully reclined and they were both allegedly fast asleep.

“I think that’s probably the media misrepresenting the story,” said Bob. “You can’t drive for long on Autopilot without your hands on the wheel – even with your hands on the wheel if it’s just a light touch. The car will alert you and then warn you, and if you ignore it, it will shut down.”

Like all other semi-autonomous driving systems from car-makers, Tesla’s Enhanced Autopilot is not intended to replace the driver but to be a computerized driving assistant. A warning screen on the large central display states that its Autosteer feature “does not make your vehicle autonomous. Please use it only if you will pay attention to the road, keep your hands on the steering wheel, and be prepared to take over at any time.” Other makers' systems display similar warnings.

Tesla’s system is often considered superior to other brands because it will automatically overtake slower vehicles, changing lanes when necessary and staying to the right, with no input from the driver. It does this through camera imagery and radar sensors, constantly sending massive quantities of data to the car’s computer system. Other advanced systems, like Cadillac’s SuperCruise, Nissan’s Pro Pilot Generation 2 and Mercedes Drive Pilot, require the driver to actually signal the lane-change manually with the indicator before making the manoeuvre.

Bob lives in the country, east of Toronto, so we drove up onto Highway 401 and he showed me how the “ramp-to-ramp” Autopilot works: ask the car to take you to a specific ramp and it will drive you there, steering itself all the way, before driving itself off at the ramp and coming to a halt at the end. Very impressive.

“I use this all the time on the highway,” said Bob. He made the point that Tesla’s overall driving safety record is much better than the average North American car, because it’s a lot smarter and more rational than the average North American driver.

We then drove on a secondary road through a small town (where I took over the controls through the traffic lights) and then onto a road with tight twists and turns. The Tesla steered itself through much tighter corners than I’ve experienced with other makes of semi-autonomous vehicles. It also knows the speed limit and automatically adheres to it, unless the driver sets a different speed.

We turned back for home. “Now I’ll show you what will happen if you ignore the warnings and try to go to sleep,” said Bob.

We got up to speed. I turned on Autopilot by pulling twice on a steering wheel stalk. The car drove itself, and after a half-minute, a notice appeared on the gauges asking me to take the wheel. I ignored it. A gentle white strip of light started flashing across the gauges, and I ignored that too.

And then the alert went away and the car carried on driving itself.

Bob, in the passenger seat, furrowed his brow. “I’ve not seen that before,” he said.

After another 20 seconds or so, the alert and flashing soft white light came back on, and when I ignored them, they just went away, as if they didn’t really matter. We carried on driving like this, no hands on the wheel and no feet on the pedals, for about five minutes until we were back in the small town and I took over the brakes. I didn’t want to fly over the railroad tracks or through a red light.

Bob couldn’t understand this. “This isn’t what it’s supposed to do,” he said.

We took another road out of town and I set the Autopilot again and we drove for about six minutes with no driver’s input whatsoever until we reached a traffic light. I pulled over. We agreed the car might have driven like this all day if it was left to do so.

Bob’s 2017 Model S is equipped with highly advanced technology, but it does not recognize traffic lights or stop signs to take them into account on rural roads. That’s coming, apparently, but it’s not here yet.

Bob replaced a faulty steering rack and pinion in June, which might have affected the Autopilot’s operation. He also updated his car’s software a week or so ago, through an app over the Internet just as you would update a phone, and it’s possible there was a glitch in that update. The point is, he’s been driving unaware that his car will not let him know when he pushes its automation too far.

He asked me not to publish his name. He was upset and perplexed by his car’s reactions, as well as a little embarrassed.

We turned back for home and this time, Bob filmed the drive with my phone. This time, the car gave me a stronger warning to take the wheel by sounding some soft chimes, but again, it then just carried on driving. It took nearly five minutes before it flashed an angry warning at me, applied the brakes, shut off Autopilot and would not resume its semi-autonomous driving until I’d parked and got out of the car.

Bob is a very good and responsible driver. However, for the past three years he’s been trusting his Tesla to help him make driving decisions and now he can no longer trust it the same way. He hadn’t even realized anything had changed. If he grows drowsy or becomes distracted, he used to trust his car to alert him, but now it might let him fall asleep and then drive through a red light or a stop sign.

Tesla is not alone in this. No system is fool-proof. Hyundais and Kias often allow their vehicles to drive on straight, open stretches of road for long periods without intervention; my record is seven minutes on the 401 in a Hyundai Palisade with my hands hovering over the wheel but without touching it. I once drove a Mercedes S-Class without touching the steering wheel and pedals for more than nine minutes through downtown Ingolstadt in Germany, crowded with traffic. Mercedes' engineers were horrified when I told them and said the car was just a “mule,” not quite ready for production.

My point is, you become used to whatever your car provides and so drive accordingly, and you grow to trust that it will react as you expect.

If Bob had a son or daughter who wanted to drive the car without knowing much about it, and who set off on a long, boring highway journey and realized the car would drive itself forever, it would be very tempting to just recline the seat and have a sleep, just for a short while.

The Tesla, like other semi-autonomous cars, is much smarter than the average driver and probably safer too. But it’s not autonomous and it’s not perfect. Both Bob and myself just had a demonstration of that.

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