A new autonomous driving taxonomy: the Driving 1-4 System

[strangecosmos]

Notes:

• This classification scheme is agnostic to driving environments. An autonomous vehicle system can be D2, D3, or D4 on the highway, but D1 everywhere else. A system can be D4 in a geofenced area.
  
  
• A higher number isn’t necessarily better or more autonomous. A D4 farming vehicle on remote dirt roads probably needs less advanced technological capabilities than a D3 vehicle in a city’s downtown.
  
  
• A fifth category is D4R: Driving 4 (Remote). This refers to when an otherwise D4 system is monitored by a remote human operator, or when a remote human operator is available to help upon request.

• This classification scheme is intended to supplement others like the SAE Levels of Driving Automation, not replace them.

 

[strangecosmos]

Examples:

D1: Autopilot.

D2: Navigate on Autopilot (with lane change confirmations).

D3: Navigate on Autopilot (with unconfirmed lane changes); a feature complete version of Tesla's Full Self-Driving Capability product.

D4: Full Self-Driving Capability with the only occupant sleeping in the backseat; Waymo One without safety drivers (D4R); Cruise Anywhere without safety drivers; Nuro grocery delivery (D4R).​

 

[Tam]

It this true because it's not in Wikipedia!

 

[strangecosmos]

It this true because it's not in Wikipedia!

It’s not in Wikipedia because I just invented it.

 

[electronblue]

That seems a little convenient... for Tesla. I mean seriously, why? It is stuff like this that makes me want to end up in Snippiness.

Anyway here’s my take on it:

The beauty of the SAE system is that it is grounded to a single, simple truth: is the car or the driver responsible for the drive and when. This system has no such consistent element.

Instead this seems like a re-classification of a narrow look at existing drivers’ aids and prototype autonomous systems, mainly Tesla’s. For example, D2 does not really define a real difference to D1. Any stable Level 2 car is D2 because they control both steering and speed and thus do not need any input from the driver other than supervision in scenarios where lane changes are not needed. Indeed what is the difference between a D3 and D2 if travelling on a single-lane road to the destination... D1-D3 only really make sense if you try to paint them with the Tesla brush (defining D2 and D3 only really make sense if you make them about lane changes), but that is no way to make an universal system...

More importantly D3 does not define a difference between car-responsible and driver-responsible driving with a safety driver. This is a really big oversight and something people consistently fail to understand and appreciate as the difference between SAE Levels 3+ and under 3. There is a huge difference between a SAE Level 4 car with a safety driver as a precaution (car responsible, safety driver a redundancy) — where the car is and is equipped and designed to be responsible for the entire driving task and capability to handle anything — and a SAE Level 2 system like NoA without confirmations which is basically an extension of a driver’s aid with very limited ability to react to road events outside the usual (driver responsible, car a redundancy).

Finally, this classification does not allow any separation for a system such as SAE Level 3 vs. Levels 2 and 4 even though again there is a major difference between a car-responsible drive that has a time-limit compared to any driver-responsible drive (SAE Level 2) or a car-responsible drive without a time limit (SAE Level 4). This would also imply grouping SAE Level 3 cars with Level 2 (because driver has to be in the car) even though the difference to required driver attention is again massive between SAE Levels 2 and 3 and two such ”D2” systems would be vastly different in the autonomy sense.

 

[electronblue]

In my opinion SAE Levels are often opposed by people in one of two camps:

1) Those who have not really grasped what it means for a car to be (even legally) responsible for the drive. These people are often the ones who rather flippantly suggest, say, Autopilot 2.5 can be Level 3 next year. In my view they usually really don’t know what they are saying. Audi’s road to this in Germany gives us some insight.

2) Those who wish to elevate their favourite Level 2 system to a ”level” it does not deserve. I know the difference in driver’s aid capability and the capability to take responsibility for the drive irks some people, but I don’t really see why this is. Being an advanced Level 2 system is no shame in itself. It is just Level 2 but it can still be an interesting product. But let’s just not try to make it into something it isn’t.

Personally I think SAE Levels are beautiful.

 

[zmarty]

I like the proposal from Lex: a system that requires user supervision vs a system that requires no user supervision. Two options. That's it.

 

[lunitiks]

I like the proposal from Lex: a system that requires user supervision vs a system that requires no user supervision. Two options. That's it.

This is the distinction between SAE levels 0-2 vs. 3-5

 

[zmarty]

This is the distinction between SAE levels 0-2 vs. 3-5

Yes, of course. But the point Lex was making is that there should be no intermediate levels. Just: it needs a human to be constantly attentive vs the human can take their mind off and sleep. There is no such thing as partial autonomy when the system is engaged. It is either autonomous (even geofenced) or not.

 

[electronblue]

Yes, of course. But the point Lex was making is that there should be no intermediate levels. Just: it needs a human to be constantly attentive vs the human can take their mind off and sleep. There is no such thing as partial autonomy when the system is engaged. It is either autonomous (even geofenced) or not.

But in reality this does not consider systems where the human can read a book or watch a video (say 10 second warning to take control). That is the point of Level 3. It is a useful distinction.

It is true that Levels 0-1 have lost their meaning a bit, the world is moving into Level 2 only especially in well equipped premium cars. Level 3 may lose its meaning over time too but currently it is still the likeliest autonomous level to reach consumer hands first... sleeping seems a long way off...

Not having a distinction for time-limited autonomy would seem like a bad thing to me.

 

[diplomat33]

My problem with the SAE levels is that it does not always line up with the car's actual capabilities. You could have a car that is perfectly able to drive on city streets without any driver intervention and be classified as L2 and people will think it is inferior to a car that is L3 but can only function at slow speeds or in certain geofenced areas.

 

[lunitiks]

My problem with the SAE levels is that it does not always line up with the car's actual capabilities. You could have a car that is perfectly able to drive on city streets without any driver intervention and be classified as L2 and people will think it is inferior to a car that is L3 but can only function at slow speeds or in certain geofenced areas.

I see what you mean, and a lot of people are sceptical to L3. However as electronblue says, Level 3 is likely to reach consumers hands first. (Unless Audi’s system or a future L3 Tesla system fails miserably in practice.)

Anyway, SAE J3016 doesn’t preclude geofenced L3 and general L2. A Tesla vehicle could theoretically in the future have a geofenced L3 mode on certain highways, but regular AP everywhere else

 

[strangecosmos]

I like the proposal from Lex: a system that requires user supervision vs a system that requires no user supervision. Two options. That's it.

I agree. A binary system like Lex’s A1 (driver assist/partial autonomy) and A2 (full autonomy) is the simplest and clearest.

This is the distinction between SAE levels 0-2 vs. 3-5

True except maybe for Level 3. Level 3 has a human in the loop. So under Lex Fridman’s schema, I believe it’s A1. Level 4 and Level 5 are certainly A2.

 

[lunitiks]

True except maybe for Level 3. Level 3 has a human in the loop. So under Lex Fridman’s schema, I believe it’s A1. Level 4 and Level 5 are certainly A2.

No it's true for Level 3. When activated, L3 is responsible for monitoring your surroundings. That means that you cannot be responsible for doing this. You don't have to pay attention. You can read, write, surf on the web.

The reason Lex Friedman and many others are skeptical of L3, is that it requires that you're awake and conscious. It expect you to be receptible to "requests to intervene". So you can't go to sleep. This is because the car will request you to take over at some point, and it does not guarantee a safe fallback maneuver ("minimal risk condition") in all circumstances if you don't take over, e.g. if there's no obstacle-free, adjacent shoulder present. In such cases, the driver is expected to take over in a "timely manner", i.e. the system must give sufficient time for a typical person to respond appropriately to the driving situation at hand. Exactly how many seconds or minutes would be up to the manufacturer (again, J3016 isn't a regulation but a taxonomy), but it would not be L3 if the driver is expected to take over immediately. There must be given some time to intervene.

So if, and only if, the car guarantees a safe fallback maneuver ("minimal risk condition") in all circumstances, is it truly L5. If it only guarantees MRC within a geofenced area, it's L4. So even an L4 system could require a "human in the loop", to take over when the car reaches the boundaries of its Operational Design Domain

 

[strangecosmos]

No it's true for Level 3. When activated, L3 is responsible for monitoring your surroundings. That means that you cannot be responsible for doing this. You don't have to pay attention. You can read, write, surf on the web.

I checked and A2 explicitly excludes Level 3 systems: “No 10-second rule: It’s allowed to ask for human help, but not guaranteed to ever receive it.”

For A2, the vehicle has to “Arrive to a safe destination or safe harbor”, which would exclude, for example, Audi’s proposed Level 3 system that just stops dead in the middle of the highway. A2 requires the guarantee of a safe fall-back manoeuvre.

SAE Levels 1-3 are A1, and Levels 4-5 are A2. (I think Level 0 is neither.)

In the D1-4 system, D1-3 are A1, and D4 is A2. (D4R is a bit ambiguous but I think it would be A2.)

On mobile, tap image for full size

Original source: 10:20 in this video

 

[electronblue]

One thing that explains Level 3 quite well is the Audi A8 (etc) Staupilot — the Traffic-jam Pilot but since it is not really discussed yet for any non-German market I think Staupilot is probably more fitting.

Here’s how it works:

- When the car enters Staupilot’s operational domain (speed limit, road type, traffic situation), it signals this with an icon on the dash
- If the driver the enganges Staupilot by press of a button, it will take over the responsibility of driving the car and show this with lights and sounds
- Video playback resumes, Internet becomes available on car screens, you no longer have to watch the road at all — read a book, whatever as long as you are awake

What happens while it drives:

- It handles all driving eventualities, including lane markings disappearing and whatever crossing the road (possibly with the exception of catastrophic things that get your attention like your tire exploding)
- It watches you all the time with driver facing cameras, in case you fall asleep — if you do, it will start waking you up immediately while still continuing to drive
- Equally if it exits its operational domain, it will start to ”wake you up” 10 seconds before asking you to take over
- In normal situations (like you reading a book) at first the ”waking up” is gentle lights and sound, eventually escalating to loud noises and physically tugging your seat belt repeatedly

If you do not respond, the car will still continue being responsible for the drive but eventually this will happen (some time after those ten seconds and additional warnings):

- Hazards will turn on
- The car will slow down to a full stop (in-lane)
- All interior lights will turn on
- All doors will unlock
- The car calls for help

This is the system as it works today. The deployment unfortunately still in the homologation inferno in Germany.

 

[electronblue]

I checked and A2 explicitly excludes Level 3 systems: “No 10-second rule: It’s allowed to ask for human help, but not guaranteed to ever receive it.”

For A2, the vehicle has to “Arrive to a safe destination or safe harbor”, which would exclude, for example, Audi’s proposed Level 3 system that just stops dead in the middle of the highway. A2 requires the guarantee of a safe fall-back manoeuvre.

On mobile, tap image for full size

Original source: 10:20 in this video

The biggest argument against Lex Friedman’s levels is this:

They are pointless in the present day.

Why have levels where everything — especially in the consumer space — for the foreseeable future is A1?

SAE Levels exist for a reason: they describe meaningful responsibility differences between present-day systems and those in the near-future pipeline. (And even in the future regarding Level 4 and 5 differences.)