Best overall adaptive cruise system

Off-Ramp
,
21

The new Ioniq 5 will have HDA II when they start selling them. On the current line up, only HDA (which is still very good).

22
  1. Supercruise/Hyundai
  2. MB (latest version)
  3. Blue cruise/BMW
  4. Toyota

2 and 3 could switch positions depending on user preference;

23

I hate the cruise control on my 2021 Subaru Forester Sport…it waits too long to brake when coming up to a real slow down and can be really jerky and scary too! FWIW, my other two Subaru (19 Forester, 2020 Outback XT) were worse…so it seems to be improving.

My Bolt EUV has fantastic CC…of course, it’s not even for sale now. And I don’t even have supercruise, which I’d imagine is even better.

24

One of things I really like about the Hyundai system is the ability to adjust how quickly you want it to response/accelerate/decelerate. Most systems just seem to have control over pacing distance, but nothing regarding responsiveness.

25

The BMW seems to follow whatever the drive mode it’s in. If it’s in economy it’s very smooth, in sport its jerky, but there is no specific setting for responsiveness.

26

There seems to be three types of systems 1- your average system with lane keep assist and following distance 2- systems like hda II and Jeeps new Level 2+ which have lane change assist and lane centering based on road conditions, but still require hands on driving (does BMW MB and Audi system fall in this category?) 3- systems like tesla autopilot Supercruise and Bluecruise.
GM says that their supercruise will only work on pre-mapped roads but have heard conflicting reports saying it will work on any properly marked highways and same about other systems that use pre-mapped sytems

27

Let’s be clear in this discussion. The Tesla system, at least for the time being, still requires full hands on the wheel use. They do not have a mass market system out that is designed to be used in a hands-free configuration. The videos you’ve seen of people climbing in the backseat, etc, are after attaching devices to the wheel to trick the system into thinking the driver is still hands-on. This is a critical differentiation between the current tesla systems and something like supercruise, which actually allows for hands free driving.

All of these systems are considered level 2 autonomy.

Back to your statement, there are quite a few more subdivisions to be had in the level 2 autonomy space.

Most basic are adaptive cruise control systems with lane keep assist. These tend to be the ones that ping pong back and forth, etc. The lane keep senses when you’re drifting out of the lane and correct. They effectively will lane follow, but are quite erratic at it.

There are systems above that with effective lane following. These are meant to actually track the lane and keep the vehicle centered. Hyundai, for example, has both a lane following assist system AND a lake keep assist on their vehicles. They do different things.

Then you have the lane change options. This is an expansion on the lane following assist, but still involves driver participation. Yah, you can “trick” a lot of the systems into handling this task without driver participation, but they’re not designed to be used in that manner (I’m looking at you Tesla Autopilot).

With ACC, there are a variety of levels of capability as well, particularly in low speed behavior. Many systems have dropped off at low speeds. The system in my wife’s Honda Passport does this. It’s designed for maintaining speed at speed. You’ll see the addition of “stop and go” to many, which will bring the vehicle to a complete stop. Most of these systems disengage after the vehicle has been stationary for a few seconds and require manual intervention to get going again. The more advanced systems will take back off again after a prolonged period.

The different ACC capabilities within the level 2 autonomy space can be broken up into these tiers:

  • At speed ACC
  • Stop and go ACC
  • Prolonged stopping ACC

Lane centering can be broken up into these tiers:

  • Lane Keep Assist
  • Lane Following Assist at speed
  • Stop and go Lane Following Assist
  • Lane Change Assist
  • Full hands free

As far as Hyundai goes, HDA offers prolonged stopping ACC and somewhere in between lane following assist at speed and stop and go LFA (it doesn’t work amazingly well at very low speeds).

HDA II offers prolonged stopping ACC and lane change assist.

Tesla autopilot offers prolonged stopping ACC and lane change assist.

Supercruise offers prolonged stopping ACC and full hands free lane following.

Audi (at least what I have on my e-tron) offers stop and go acc with somewhere between lane keep assist and very mediocre lane following assist.

Tesla FSD is a different discussion

5 Likes
28

do the systems that take off after prolonged stop know that you are not at a stop sign? I always thought that the grace period of a stop and resume automatically was becase the system has no idea of what the situation on the road is.

29

All the systems that I have used that will hold for a prolonged duration are for use in stop and go traffic. They don’t have awareness of stop signs/crossing traffic, nor would I really trust them to at this point. You’re really talking about level 3+ autonomy at that point.

Audi has a system that is contextually aware of stop lights in certain situations (even displaying a count down on the dash for time remaining on the light), but I don’t know that it feeds into the ACC.

30

Let’s start off by assuming stop signs are posted on single lane roads that are mostly low mph limit, so most systems won’t even operate at all. Now assuming your system is still on, it will stop for one of two reasons, either the car in front of you stopped and as soon as that car moves it will just follow without stopping again for the sign, or you will stop because you braked for the sign manually which will have shut off your system until you restart it, unless you have Tesla fsd or similar of course which isn’t technically ACC.

31

insert ones own opinion here because this is the brand of vehicle I drive or the brand I work for

1 Like
32

stop and go systems will operate at low speeds. For example my BMW will set the lowest at 20mph, but will happily crawl in traffic and 2 mph behind another car. When the car in front of me stops, mine stops but the system remains on. if the car in front will move within 2 or 3 seconds, mine will continue going. If the car will not move for 3 seconds, and then starts again, I have to press the accelerator or “res” button to continue forward.

My MDX prior worked the same way.

BMW system even has a slight tolerance to the brake press. If I gently nudge the brake to slightly slow down, it won’t disengage the system, if I press on it or ride if for more than a second or so it will disengage.

Since there are no standars, all of these systems do whatever the manufacturer thinks is a good idea. For example MDX disengages lane keep assist (not the warning) when you brake. BMW doesn’t. BMW can steer based on a car in front, MDX couldn’t and needed lanes. and the list goes on and on.

33

Very useful info. However, I am a bit confused about the Hyundai system.
HDA seems available only on highest trims for each model. Many base models come with ACC+LFA. How are these two different? Hyudai’s ACC is called ‘Smart Cruise with Stop and Go’. I assume that it does things for stopping as well. How is the HDA better if ACC+LFA (from lower trims) is doing same thing?

34

I heard recently about comma. It’s an aftermarket system that overrides the ACC+LFA from OEM. As far as I see from Youtube videos, their system is much much better than factory system and comparable to Tesla. They seem to have some software update which can do lane change as well.
It costs 1k/2k

35

Hyundai does a horrible job of differentiating what HDA offers offer the system in lower level vehicles.

From playing around with the system, and testing it in a variety of conditions with HDA engaged and disengaged (so I’m assuming that not having HDA acts the same as HDA being disengaged), you gain the following features over non-HDA:

  • ACC automatically adapting to speed limit changes (note: this only works if ACC is set AT the speed limit. There’s no offset available)
  • Extended periods of “handsfree-ness” (takes much longer for the car to yell it you to grab the wheel with HDA engaged than without)
  • Extended periods of sitting stationary in stop and go traffic before the system requires you to tell it to go again

Of those three, only the first is advertised by Hyundai.

2 Likes
36

Got it. Thank You. That makes sense since it mentions Highway in HDA. I am assuming that this doesn’t make much of a difference in freeways. It should be good with ACC+LFA I believe.

37

HDA is only active on controlled access roads.

1 Like
38

so what does it do on a local street?

39

Doesn’t do the three bullet points, so disengages quicker after stopping (still longer than most every other system I have used), makes sure your hands are on the wheel more often, and doesn’t auto adjust the acc speed to changing speed limits. Still does everything else you’d expect.

40

Got it, I was curious if it reverts to some basic thing when not on a designated highway, but it sounds like it just goes more nanny state.