We are now seeing SAE Level 2 systems at the forefront of current introductions and upgrades from (mainly) upscale car brands. Cadillac Super Cruise, Nissan ProPilot 2.0, and BMW’s x5 Extended Traffic Jam Assistant all explicitly allow hands-off and verify via driver monitoring that the driver is doing his or her part scanning and reacting to the environment. Tesla and others require hands-on-wheel while providing some degree of lane centering support, but this might be limited to well-structured roads. Level 2 -- defined as “sustained control” of lateral and longitudinal control (steering and foot pedals, respectively) -- encompasses a wide range of steering support.
What Level 2 doesn't do, as I noted recently, is provide Object and Event Detection and Response (OEDR). This remains the driver’s job in Level 2. Level 3 features go the next step to provide sustained control plus OEDR. Level 3, or “conditional automation,” is mid-way in the driving automation spectrum. Level 3 Automated Driving Systems (ADS) handle the Dynamic Driving Task (DDT) within the defined Operational Design Domain (ODD). If the vehicle encounters conditions that pop it out of it’s ODD, that human in the driver’s seat is the “fallback” for maintaining safe operation. For example, a Level 3 Traffic Jam Pilot designed only for low-speed operation would exit its ODD when the vehicle’s speed increases as traffic clears. So, when deemed necessary, the Level 3 ADS issues a request for the “receptive fallback-ready user” to intervene and achieve a safe state. How to ensure this happens gracefully is a matter of system design; therefore, it is not specifically addressed in the SAE definitions. Level 4 takes the human out of the loop completely; the ADS itself is the fallback.
Because DDT and OEDR are being performed by the ADS, I refer to Level 3 as a system that allows “hands off, feet off, eyes off” with “brain on” so that hands, feet, and eyes are readily available.
When can we start driving a vehicle equipped with a Level 3 feature? A few years ago, Level 3 was being discussed as a natural step beyond Level 2. For example, take Audi’s bold pronouncement that the 2018 Audi A8 would offer a Level 3 Traffic Jam Pilot. They did so, and although vehicles could be purchased with this feature in Germany, once on the road lack of clarity with German road regulations forced Audi to refrain from enabling it. Ouch.
Level 3 systems are risky because of the human element. As cars creep along in a traffic jam, the consequences are modest if a driver doesn't properly take over when requested by the ADS (Audi set the take-over time at 10 seconds). In such a case the car is programmed to simply stop in-lane and activate hazard flashers. Inevitably the honking of nearby car horns would make an indelible impression on the recalcitrant driver to not repeat this stunt.
Full speed range operation is of course much more valuable to customers than a system that is only useful when the traffic is terrible. But at high cruising speeds, the safety implications of human drivers not doing their part increases exponentially. As automakers grappled with the challenges of ensuring that the driver is available to take over when requested, the human-related unknowns translated to significant and somewhat uncontrollable risk for these systems. The thinking then shifted to “Wait! Why beat our heads against the wall with shared human-computer responsibilities when we can just jump to Level 4?”
The Level 4 frenzy ramped up quickly. For me, the peak was at CES 2017 when Scott Keogh, President, Audi of America, appeared with NVIDIA founder Jensen Huang to announce a new partnership for self-driving products. Keogh said they would introduce “production level four autonomy automation” by 2020.
Anticipation was at a fever pitch but…over time, commercial Level 4 products started to look out of reach for the near term. This is when automakers began jumping on the robo-taxi bandwagon, seeing fleet operations as the proper incubator for such high capability, high-risk systems. Their premise is that learning and validation from offering robo-taxi fleet services will eventually provide sufficient confidence to put similar vehicles into the hands of private owners.
By early 2018, I was convinced that Level 3 was off the table, due both to regulatory challenges as well as fundamental technical factors, even though other automakers had also promised imminent Level 3 features. So, it was goodbye Level 3 and get comfortable in your Level 2 car while you sit back and wait quite a while for Level 4.
However, about this time last year Mercedes teased us with the possibility of the 2020 S-Class being equipped with a Level 3 feature. OK, maybe, I thought. At Tesla’s Autonomy Day earlier this year, CEO Elon Musk stated L3 (or higher) will be available very soon. Again, maybe (I take all Tesla announcements with a grain of salt). Then earlier this year while visiting automakers in Germany, I learned that BMW’s 2021 iNext will offer a full-speed range Level 3 feature. Now we’re talking! While BMW’s press statements are definitive, Mercedes, a year after the tease, shows no indication that the 2020 S-Class will be Level 3 equipped. We’ll see what Tesla brings to the fore.
The key to this change of heart was in new ways to reduce risk. In BMW’s case, I was told the system will only work on specific roads that have been approved as satisfying the ODD parameters. This could relate to limited-access divided highways, good lane markings, and any number of other factors. Furthermore, if poor weather or other conditions threaten to create a situation not within the ODD, BMW can remotely disable the feature via the vehicle’s cloud connection. Thus, my 2021 iNext can be chauffeuring me along the Autobahn, allowing me to take a few photo’s of the Bavarian countryside on a sunny autumn day when the system prompts me to take over. I reluctantly put down my camera, and the system provides full control while I re-set myself from passenger to driver. A few moments later as I crest a steep slope it all makes sense, as I’m in a sudden snow squall.
This idea of “tethering” the vehicle system to real-time conditions is a completely new phenomenon in driver assistance systems. Cadillac Super Cruise pre-maps a large network of limited-access highways where the system can be engaged, and the system will or will not activate based on a static database. The BMW approach, which I expect we’ll see from others, requires the carmaker to implement back-end systems that can make assessments moment-by-moment. This is an effective way of reducing risk, but it also creates a significant responsibility and surely comes at significant cost.
Automakers have never before been engaged in such close-at-hand decision making for a feature on their vehicle.
It has not yet been revealed how will these new vehicles will handle the risk of the driver not doing their part. Intense development of Level 3 human-machine interfaces has been underway for years. Certainly they will build on Level 2 driver monitoring systems.
Has the regulatory quagmire for Level 3 operations been resolved? This is being quietly worked by auto manufacturers with their government counterparts, a process underway for some time now. There have been some changes to German law, and the legal landscape in the U.S. continues to evolve. There is more work to do and these factors could affect timing, especially for the German OEMs.
Indeed, we now appear to be very close. When I boil it all down, the only solid indication is BMW’s 2021 model. But Audi has the technology built into their cars, they only need to turn it on. Mercedes has it on their roadmap and “soon” seems a reasonable expectation. Just because Mercedes has been quiet doesn't mean they aren’t readying a little surprise for BMW and their other competitors. Compared to a couple of years ago, it’s not as competitively urgent to call out that next Level nowadays. Instead, it’s more like the regular evolution of product in the car business. Much healthier, I would say. Vehicles for Model Year X are usually released for sale late in the year prior. So, will 2020 be the Year Of Eyes-Off? Given the players involved, it's looking good.
