October 7, 2024
Have you ever noticed that the Batmobile has automated functionality? That’s right; 30 years before automation became the talk of the transportation world, it powered up a superhero’s allure. Idolization of automated vehicles, or AVs, threads even farther back into the fabric of pop culture, all the way to David Keller’s 1935 short story called “The Living Machine.” Originally fantasies, these stories are increasingly looking more like our reality.
Automated shuttles, robotaxis, automated trucks, and sidewalk delivery robots now populate the streets of some cities from San Francisco to Miami. But in late 2023, Mercedes Benz changed the game by rolling out the DRIVE PILOT, bringing the first Level 3 automated vehicles into consumer markets in the United States—and a once-hazy future of autonomous cars a little more into focus.
Higher levels of automation offer the potential for a myriad of benefits, including multimodal road user safety, emissions reductions, and economic productivity. But reaping these benefits requires experimentation, leaving us in a transitional phase where many vehicles of different automation levels are sharing the road, and there is widespread confusion for drivers on what exactly their roles are. Let’s take a closer look at breaking down automation.
Automation occurs on a spectrum, which the Society of Automotive Engineers (SAE) has divided into six levels, ranked 0 through 5.
What Are the Levels of Vehicle Automation?
Many assume that AVs are black and white: either there is a human driver, or there isn’t. But autonomy encompasses a vast gray area. Automation occurs on a spectrum, which the Society of Automotive Engineers (SAE) has divided into six levels, ranked 0 through 5.
In Levels 0, 1, and 2, the human is responsible for driving, but has driver support features. Level 0 only includes warnings and momentary assistance, which might look like an alert when drifting outside lane lines or automatic braking when coming too close to another vehicle. Level 1 includes steering control (such as automatic lane centering) or brake/acceleration support (such as adaptive cruise control), while Level 2 includes both. These all fall under the category of Advanced Driver Assistance Systems (ADAS), which are designed to reduce crash frequency and crash severity while still necessitating human participation.
Since 2013, a variety of car models with Level 2 technologies that steer, brake, and accelerate for the driver have been rolling out in waves from Audi, BMW, Ford, General Motors, Infiniti, Kia, Mercedez Benz, Nissan, Tesla, Toyota, and Volvo. Many already view Level 2 cars as self-driving, as ADAS can offload much of the active work of driving. But Level 2 is by no means autonomous and can pose dangers when drivers are under the impression that the car can do more than it can. When used properly, however, these systems save lives by preventing run-off-road or rear-end crashes of distracted, impaired, or drowsy drivers.
Levels 4 and 5 do not require any active participation from the person in the driver’s seat when the system is engaged; the “driver” essentially becomes a passenger. The difference between Levels 4 and 5 lies in the range of the vehicle itself. Level 4 must be operated under required conditions set by the manufacturer, but Level 5—which some debate is even possible to achieve—can drive “everywhere in all conditions,” according to SAE.
Level 3 is the wild card of the group. Described as “conditional automation,” sometimes the system drives and sometimes the human must drive. Automated systems drive only under specific conditions, called the Operational Design Domain (ODD). The conditions for engaging Mercedes Benz’s Level 3 DRIVE PILOT are that you must be driving under 40 mph, on certain divided highways with readable markings and lane lines, in clear weather, during the day, without any intersections or traffic control devices (like stop signs or traffic lights), and not in a construction zone. As Level 3 vehicles are popularized in the automobile market, consumers need to know the practical reality of driving within conditional automation.
DRIVE PILOT includes an entertainment system but still "requires an alert and attentive driver to supervise its performance," creating a challenge for drivers and transportation agencies balancing alternate activities with constant supervision.
Level 3: The Middle Child of Vehicle Automation
The ability to automate only under ODD conditions isn’t the only catch to Level 3; in DRIVE PILOT, the vehicle’s Automated Driving System (ADS) can also request the human to take over driving at any point. The system may do this when it encounters a situation it doesn’t know how to handle or when it leaves the ODD. The way in which an ADS alerts the driver they need to take over can vary; not all automation systems will communicate the same way that DRIVE PILOT communicates.
The DRIVE PILOT also has an entertainment system including movies, television, built-in games, trivia quizzes, a web browser, and, in E-Class Mercedes, Zoom and even TikTok—all of which is unlocked when the ADS is activated in the right conditions. However, the company specifies in the owner’s manual that the system “requires an alert and attentive human driver to supervise the feature’s performance.” This balance between the option for alternate activities and the necessity of perpetual supervision puts drivers and transportation agencies in potentially difficult positions.
There is extensive ongoing research being conducted that might help guide state and local agencies. The National Cooperative Highway Research Program (NCHRP) is working on several projects that relate to developing AV systems and accommodating them on roadways. Kittelson is also currently leading a pooled fund study to create a succinct guidebook instructing State DOTs on how they can prepare roadway infrastructure for successful integration of AVs.
Sites like NHTSA and IIHS set government-standard and private-standard safety expectations for vehicle developers and display performance ratings for specific crash avoidance features.
Automation Isn’t Your Chauffeur—It’s Your Co-Pilot
As we wait for more comprehensive guidance from manufacturers and DOTs, what can you do? It’s critical that drivers educate themselves before driving a vehicle of any level of automation. For ADAS, read up on how your vehicle works using resources like My Car Does What?, from Iowa Driving Safety Research Institute. Ensure that you never drive intoxicated or drowsy, and that even when your foot doesn’t need to be on the gas pedal, you pay attention to the road. Monitoring the function of your vehicle is one the most important things you can do. with an AV. If you’re a parent or teaching someone to drive, instill this vigilance in young drivers as well. As an example, Maryland became the first state to update its driver’s manual for new drivers with substantial information on ADAS.
If you drive a car not equipped with an ADAS or ADS, be aware that these vehicles are on the road around you. Mercedes is planning to develop turquoise marker lights on their Level 3 cars so that others can identify when the system is engaged, so keep an eye out. You can also peruse NHTSA’s TEST Initiative AV tracking tool to see in which areas automated shuttles and robotaxis are active. If you’re planning on buying a vehicle with ADAS or L3 capabilities, browse NHTSA and IIHS safety rating websites to search the model you’re interested in. These sites respectively set government-standard and private-standard safety expectations for vehicle developers and display performance ratings for specific crash avoidance features.
And as we prepare for more Level 3 vehicles to come to the U.S., learn about experts’ opinions on Level 3, like those interviewed by NC State Humanities and Social Sciences News. As our understanding of what constitutes “distracted driving” shifts, stay cautious of where your attention is even if you choose to engage in a legal, secondary activity while an ADS is driving. With diligent critical thinking and awareness, you can do your part to utilize AVs safely and better prepare for our road systems for a future where Level 3 could be increasingly commonplace.