The Society of Automotive Engineers (SAE) is an organization dedicated to developing standards for the automotive industry globally (you’ll see their name come up again in the charger lessons). They've defined 6 different "levels" of automation, from "0" through "5". Each level gets more advanced with additional autonomous features. Let’s walk through each.
Level 0 is a car without automation. This is any car that is fully controlled manually by a human driver. Level 0 cars might still have driver assists like traction control or automatic emergency braking, but since these features don’t steer or accelerate the car, they don’t count.
Level 1 is the lowest level of automation. It means that the car has only one feature that either steers or accelerates the car (but not both).
The most common example of Level 1 automation would be Adaptive Cruise Control (ACC), which is cruise control that matches the speed of a car in front of you. Because ACC systems will accelerate automatically if the car in front of you speeds up (up to the cruise control speed that you've set), they count as a single automation. The driver, meanwhile, is still manually controlling all other aspects of the car (steering, etc).
Level 2 vehicles can feature two different automations at the same time - such as steering AND acceleration. An example of this would be systems that combine Adaptive Cruise Control with Lane Keeping, or a system that monitors lane lines and will apply corrective steering to keep you in a lane. Tesla’s Autopilot and Cadillac’s Supercruise, two of the industry’s most popular autonomous systems, are currently level 2 systems.
This is where it starts to get weird, as anyone who has driven a Level 2 system can attest. Level 2 systems can start to feel like the car is driving itself. After all, it is staying in its lane and adjusting its speed as needed, but it’s critical to remember that the car is NOT in full control and that the driver must continue to actively monitor their surroundings and be ready to take full control on a moment’s notice. Drivers get into serious (and sometimes fatal) trouble when they get lulled into a false sense of security by these systems.
So why bother if the driver has to stay alert and engaged all the time? Because these systems DO offer a reduction in stress while driving in traffic or over long distances. These cars have sensors such as radar, cameras, and occasionally LiDar, and are capable of reacting to certain situations faster than a human reaction could. The problem is, these systems sometimes fail to accurately interpret the world around them, and must be closely monitored.
If Level 2 was weird, just wait until Level 3. Level 3 cars have a degree of “environmental awareness”. They can monitor their environments and make decisions on behalf of the driver. An example of this might include changing lanes to pass a slower car on the highway, WITHOUT input from the driver. Weird, right?
Under level 3, the car takes on the primary role of monitoring the environment but the driver must still always remain ready and able to take control immediately when and if prompted.
Level 4 vehicles are capable of driving themselves fully under many circumstances, but the driver may still need to intervene and take control. An example of this would be a geofence, where the car works with full autonomy inside well-mapped city limits, but needs driver input outside of that pre-defined area.
We do not currently have Level 4 vehicles on sale in 2022. It is likely that laws will also need to change before Level 4 autonomy is allowed to operate widely on public roads.
For now, this one remains hypothetical.
Level 5 is the holy grail of autonomy. At Level 5, a steering wheel is optional. This is 100% autonomous, capable of navigating all situations without human input.
At Level 5, imagine pulling out your phone and requesting a robot taxi. A car arrives with no driver, and unlocks itself for you. It will drive you to your pre-programmed destination, while you browse the internet or perhaps get some work done. When you arrive, the car drives away. Maybe you own the car, and it drops you off and looks for parking on it’s own, drives home, or earns income by offering rides to others. This is a strange and interesting future, and it’s coming!
There’s no telling when we’ll reach true Level 5 autonomy. Automakers and some of the biggest tech companies are racing to be the first to offer truly autonomous mobility. Some say it’s only a few years away, and others estimate a decade or more.