The Key Differentiator Between SAE Level 2 And Level 3 Automated Driving - Forbes
In the blizzard of recent opinion pieces concerning new introductions of automated driving features in mass market automobiles, a few mis-understandings have started to float around that I will address here, hoping they don't propagate further.
Last month Nissan’s ProPilot 2.0 was announced for the Japanese market only. Initially available on the upscale Skyline model, there are ground-breaking features such as automatically negotiating freeway-to-freeway interchanges. Very impressive stuff and I’ve been prodding my Nissan colleagues to accelerate North American introduction! But of course they remind me that adapting a complex system to another region with different traffic dynamics and road rules is quite an involved process and must be done carefully. All vehicle manufacturers take this approach when introducing driver assist systems in disparate markets, but I’m nevertheless impatient.
A recent article unfortunately characterized ProPilot 2.0 as an SAE Level 3 system. Others have referenced this article such that this carefully designed Level 2 system is now being wrongly framed. Let’s nip this in the bud.
As a start, a review of the capabilities implemented by Nissan in ProPilot 2.0 are in order. The Nissan system evokes the Cadillac SuperCruise™ system introduced in 2017, which controls steering, braking, and throttle while on an approved highway, as long as the driver is continuously monitoring the driving environment. GM added a driver monitoring system which is key to allowing hands-off capability, providing some degree of confidence that the system is being used responsibly. ProPilot 2.0 goes one step further with “navigated driving,” providing ramp-to-ramp highway driving based on a route entered into the navigation system by the driver. The system supports hands-off driving while cruising in a single lane; when a lane change is needed, the driver is prompted to place their hands on the wheel and press a button to approve the maneuver, what I call a “supervised lane change.” The system then safely controls steering, brakes, and throttle to perform the maneuver based on data from sensors that can see in all directions. For the freeway-to-freeway interchange feature noted above, ProPilot 2.0 handles a lane branching in two directions, based on the designated route.
Nissan stresses that the driver must remain attentive and be prepared “to immediately take manual control of the steering wheel when conditions of the road, traffic, and vehicle require it.” Similar to SuperCruise, lack of response by the driver will cause the vehicle to activate hazard lights and come to a graceful stop, opening an audio connection with an emergency call center.