Self-driving Cars: Autonomous Levels Explained
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Self-driving Cars: Autonomous Levels Explained

Autonomous cars are having a bit of a moment these days, with new projects from Arrival, Tesla, Toyota, and Volvo coming online with “Level 3” and “Level 4” technology— but what does that mean, exactly? And why is there a picture of a black Trans-Am up there?

Autonomous cars occupy a weird space in the modern American psyche. To some, they’re part of a futuristic, Utopian vision of safer, cleaner vehicles that could fundamentally change the nature of transportation ownership for the better. To others, they represent a bleak and soulless tomorrow that will see entire industries gutted, leaving millions unemployed. To others still, it seems like they’ve already been around a while, in some form or another, and nobody really seems to care– and that’s where things tend to get tricky and people start asking questions.

As such, we’ve decided to answer a few of the most common ones that have come up about self-driving cars and what they’re all about in our latest Electrify News Explainer.


Level 0 | Zero Automation

Image courtesy Chrysler.

This is the easiest level of autonomous car to understand. Simply, this is a purely analog car with an accelerator pedal that is physically attached to a cable that’s physically attached to a throttle body somewhere that opens up and allows an engine to suck in more air and fuel. There might even be a clutch pedal, too– and any braking or steering assistance is provided by a mechanical vacuum or hydraulic pump, as opposed to an electric motor.

The car goes when you stomp a pedal, turns when you turn a wheel, and stops when you stomp the brakes, ONLY. If things get hairy and sideways there is no one– or no thing– there to save you.

So, while this is probably the easiest level of vehicle autonomy to understand, it is probably the most unfamiliar to our readers. Think about it: when was the last time you saw a car that was completely manually operated? Name a car built in the last two decades that wasn’t at least available with an electronic, anti-lock braking system. How about something as basic as cruise control? Heck, most cars today can be had with a traction control system that would have made headlines if they’d debuted on a mid-90s era Formula 1 car. Even that Chrysler K car up there had an automatic transmission AND cruise control— in 1988!


Level 1 | Automation to Handle the Emergencies

Image courtesy Volvo Cars.

While Level 0 autonomy is probably the most conceptually familiar level of autonomy to most of us, Level 1 is the one that’s most actually familiar. This is where most modern cars live today, with those beep-beep “parking sensors” feeding data to a distance-keeping cruise control and sudden stop systems while advanced, sensor-driven traction controls use electronically-controlled braking and torque-vectoring systems to mimic the type of steering inputs necessary to keep the car from sliding or spinning out in the rain and snow.

Keep in mind, we’re not talking about high-end, super-expensive luxury car stuff here. This is all technology that can be had on even budget-branded products from mainstream brands like Hyundai and Kia. It’s technology that comes into play in that critical 0.001% of the time that we’re driving in the most extreme conditions and, most importantly, it is technology that we already trust to intervene when we need it most.


Level 2 | Automation to Handle the Annoying Bits

Image courtesy

We’ve come to understand the “zero automation” cars of the past and the “driver’s assistant” cars of today pretty well. So, here, we can begin talking about the kind of cars that most people think of when they say “autonomous cars”. These are vehicles that use adaptive cruise control and lane-keeping systems to “take over” for drivers on long, boring road trips when their minds might start to wander. Vehicles that can read traffic signs, slow down and speed up to match posted speed limits, and– once you get to where you’re going– might even park itself for you.

If you’ve been driving high-end luxury cars from manufacturers like Acura or Mercedes-Benz or Volvo in the last decade, this will all sound very familiar. In fact, this is about the level that Tesla’s early Autopilot software operated at, in the sense that the car will keep on keeping on the highway it’s on, responding to other cars’ movements and such.

The takeaway here is that, while these systems are pretty advanced compared to what was available a few years ago, the driver is still ultimately responsible for the car’s actions.


Level 3 | Automation to Handle the Mild Inconveniences

Image courtesy SlashGear.

Audi claims its Audi A8 was the first vehicle to offer Level 3 automation. At Level 3, the driver can take their attention off the road for extended periods of time while the software takes over all of the vehicle’s longitudinal and lateral controls. All of the stopping, going, and turning, in other words. Here, the driver only takes over in situations where highly detailed digital maps either don’t or can’t exist (think “country roads” or “new construction”).

At this stage, the driver is probably still legally responsible for what happens, but the car is really the one monitoring the trucks, cars, bikes, people, and animals on your route, and the car is making big decisions almost all of the time. When it works, it looks like this …

Image courtesy Volvo Cars.

… but, when it doesn’t work …

Image courtesy BBC.

… and people start to mistrust and fear autonomous cars. You start to see stories sensationalizing crashes like this one (above), from 2020, where a Tesla crashed while its driver was playing video games. Or, worse, exploiting some of the fatal Autopilot crashes Teslas have been involved in in recent years for their own purposes— and their own purposes don’t always have the public’s best interests in mind.


Level 4 | Automation to Handle Your Commute

Image courtesy CleanTechnica.

This is where the latest version of the Tesla Full Self Driving product lives. At this level of automation, your car still has something that looks sort of like a steering wheel, but you probably haven’t used it in a while. In fact, you may even be able to push it aside to make room for a book, a laptop, or your favorite show …

Image courtesy Tesla.

… all you really need to do to get from A to B in one of these is hop on your nav screen, enter your destination, and let the car handle everything from pulling out of the parking space to finding one when you get there. You, meanwhile, are reading, texting, or (most likely) checking your work emails. You’re too busy to be bothered by any of that actual driving!

This is the self-driving car of near-future science fiction TV and movies, and also the version of autonomy most people probably think of when they say something like, “autonomous cars are coming”.

So, Level 4 is the one that’s going to get people really excited. It’s also very much the level of automation that’s going to get a lot of people really unemployed, too. In the US alone, there are almost 3.5 million professional truck drivers. That’s according to estimates by the American Trucking Association, who also count the total number of people employed in the industry– dispatchers, schedulers, HR reps, and others– at more than 8.7 million. That’s fully 8.7 million people who might find themselves unemployed just about the minute it becomes more cost-effective to pay for a new, robot truck vs. a new, human driver.


Level 5 | Automation to Think for You

KITT, from Knight Rider. Courtesy NBC.

Tesla Technoking Elon Musk once famously said, “All input is error.” Whatever you think of Musk or his views on humans behind the wheel, it’s time to face facts: by the time we get to this level of autonomous driving, your car won’t just be as good as you, it will be better.

At Level 5 automation, your input is no longer needed. The car is more than capable of being told where to go, and finding its way there. In extreme cases, a Level 5 autonomous car would even detect if you, for example, lost consciousness. It would then be able to decide if it should call for help, or just take you to the hospital on its own— maybe even while it calls for help. Oh— and, while it’s making decisions like that, it’s also driving more safely and more efficiently than you can. Heck, it probably doesn’t even have a steering wheel.

As for that black Trans-Am? If you’re over 40, you already know that that’s KITT— the famous, artificially intelligent, self-driving car that (along with Airwolf and the A-Team) shaped the hearts and minds of Gen-X gearheads forever.



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5 Responses

  1. Teslas are NOT level 4. They are still level 2. They still require an attentive driver. Waymo is level 4.

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