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Discussion Starter #1
I know that the lack of adaptive cruise control (ACC) in the Bolt it has been discussed a bit in this forum, so apologies if you have moved on. :) However, the lack of this feature originally gave me pause before buying my Bolt, which seems such a no-brainer in new cars. So, I was surprised to learn that its absense was intentional, at least based on the InsideEV article of their interview with the Bolt's Chief Engineer and the lack of "blended braking". (https://insideevs.com/exclusive-inside-the-chevrolet-bolt-with-its-chief-engineer-new-details/)

But, I am just not convinced that there is a hardware limitation here that would prevent its implementation in a software update. The fact that I can manually change the cruise control speed from the steering wheel (yes I know this is true of most any car with this feature ;) ), which is a logical change and not a physical one involving the brake pedal, begs the question: what prevents this being accomplished through software automation? For instance, the same stream of information used for forward collision alert (FCA) and forward automatic braking (FAB) could in theory also be used to automatically increase or decrease vehicle speed based on distance values detected between the Bolt and the car in front. I'm not suggesting "hijacking" the FCA/FAB systems. These should absolutely still operate when the requisite threshold in distance detection is breached as they normally work today. What I am suggesting is that when cruise control is engaged and the threshold is not breached, the values being detected could be continuously processed to determine how much to decrease/increase the car speed to maintain the requisite safe distance between the Bolt and the other car and then adjust the speed accordingly.

Thoughts? Any GM engineers lurking and want to respond? ;)
 

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Level 2 or more 'auto drive' would make the Bolt almost perfect for me, coming from a Tesla Model S with their auto drive system (1st Hardware version), which was quite good in my opinion.

Here is one option that may be possible with hacker help: DIY Auto Drive
 

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I just test drove a 2018 Nissan Leaf, and that adaptive cruise control (Pro Pilot) worked fantastic when we tested it out, going from open freeway to stop and go. Seems strange that Chevy won't enable that on the Premier as it seems it has all the necessary sensors and already offers all the other features that Nissan bundles together as Pro Pilot. I don't get the blended brakes argument against it, especially since the Bolt does have blended brakes, just a different implementation than the Volt had (The chief engineer was either misquoted or misspoke).
 
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The same sensors MIGHT work, or there could be different requirements for adaptive cruise control sensors from collision avoidance sensors.

For adaptive cruise control you may need longer-range sensors as well as sensors with a wider field of view (ones that look to the left and right of the car). Early adaptive cruise controls would have this problem. As the lead car went around the corner in the freeway, the car in front of you would "disapear" from the sensor's field of view. Your car would then speed up, possibly too fast for the corner. Even if it was not too fast for the corner, the car may then slam on the brakes as the road straightened out and the senors re-discovered the lead car, only now much too close since the car had sped up.

I wouldn't assume that collision avoidance sensors would be good enough for a safe adaptive cruise control system.
 

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Discussion Starter #5
Level 2 or more 'auto drive' would make the Bolt almost perfect for me, coming from a Tesla Model S with their auto drive system (1st Hardware version), which was quite good in my opinion.

Here is one option that may be possible with hacker help: DIY Auto Drive
Thanks for the tip! However, I’m looking more for a “baked-in” solution rather than a “bolt-on” (no pun intended! ;) )

Also, they’re charging 1.0 bitcoin or as they list it “$999”. With bitcoin nearly $10,000 per at this point, I’d just pay in dollars. ;)
 

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Discussion Starter #7
The same sensors MIGHT work, or there could be different requirements for adaptive cruise control sensors from collision avoidance sensors.

For adaptive cruise control you may need longer-range sensors as well as sensors with a wider field of view (ones that look to the left and right of the car). Early adaptive cruise controls would have this problem. As the lead car went around the corner in the freeway, the car in front of you would "disapear" from the sensor's field of view. Your car would then speed up, possibly too fast for the corner. Even if it was not too fast for the corner, the car may then slam on the brakes as the road straightened out and the senors re-discovered the lead car, only now much too close since the car had sped up.

I wouldn't assume that collision avoidance sensors would be good enough for a safe adaptive cruise control system.
Yes, different detection hardware requirements seems a better argument than different brake hardware for not including ACC as an option. But that’s not what the article indicates, so that’s why I think there is more to the story (and maybe a glimmer of hope?)

It would be nice if GM could confirm your hypothesis is correct, otherwise give us an expected release date for the feature! :)
 

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Now that Nissan has ACC in the new Leaf, GM has to add it. Everyone wants it and it's becoming more and more common, so they will need to get on it. I guess the 2018s aren't going to have it, but I sincerely hope the 2019s do as by then Nissan will have the Leaf with the bigger battery available and there will be less and less reasons to buy a Bolt.
 

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I’m starting to wonder the same, but I’m assuming he was quoted from a transcript of the interview, and he seems pretty emphatic.
Bosch confirmed the Bolt has blended breaking (they provide the hardware), and it is easy enough to test yourself. Get up to speed in D mode, apply the brakes. Does the car generate regen? If yes, the car has blended brakes. If you didn't have blended brakes you wouldn't get any regen when applying the brakes. It was hashed out pretty thoroughly on the GM Volt forums (talking about the Bolt), but easy enough to test for yourself. They also get into exact numbers of the level of regen you get in different modes.
 
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{Speaking from never having driven with adaptive cruise control}: It would seem that ACC would work better if other drivers would not jump into that space between you and the car ahead. Even on the ">>>" setting, the collision avoidance lets me get pretty close before the beeps and blinks begin. If I stay back a "reasonable" distance in ACC, will other drivers leave that space alone? Will it work best if ALL drivers are using CC, even if not ACC? Will it work best if ALL drivers are driving at or below the speed limit? If we ALL drove the speed limit, ACC would be a easy adoption.

Which brings me to an autopilot question: My GPS (Garmin) knows (and displays) the speed limit on all the streets on which I drive. It visually warns me if I exceed this limit. Will autopilot mandate the EV to drive at or below the posted speed limit? I cannot believe that you could get up to 80 (or >) mph and put it on autopilot. Will it allow 5 mph over? Will it allow a certain percentage (say 10%) over the limit? Will it have limited usefulness until "everyone" has autopilot?
 

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Will autopilot mandate the EV to drive at or below the posted speed limit? I cannot believe that you could get up to 80 (or >) mph and put it on autopilot. Will it allow 5 mph over?
AutoPilot on the Tesla works up to 90 MPH with no limit on highways with center median and 5 MPH above speed limit on roads without center median. Generally, works well in my experience with their 1st Gen hardware.
 
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If there's the slightest chance of an accident caused by the combo of ACC and regen braking, GM will hold off. Had ACC on my Cherokee: Not that special.
 

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Discussion Starter #14
Bosch confirmed the Bolt has blended breaking (they provide the hardware), and it is easy enough to test yourself. Get up to speed in D mode, apply the brakes. Does the car generate regen? If yes, the car has blended brakes. If you didn't have blended brakes you wouldn't get any regen when applying the brakes. It was hashed out pretty thoroughly on the GM Volt forums (talking about the Bolt), but easy enough to test for yourself. They also get into exact numbers of the level of regen you get in different modes.
Yup, tested it out myself and confirmed: blended braking in my Bolt! I guess I never noticed this since I’m always in “L”! ;)
 

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Discussion Starter #15
that insideevs article is two years old (i really wish they'd put an actual date on things...). anyway, i'm sure it was too late to make changes to the brake system at that point.
I guess I should check my sources and how current they are before trusting them! :) So, yes the whole blended braking thing is a red herring as I had already suspected.

But back to my original inquiry: is ACC possible via a software-only update?
 

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But back to my original inquiry: is ACC possible via a software-only update?
Even if it were, I doubt GM/Chevrolet would allow it (too many legal concerns)

But I bet Elon Musk would :)
 

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The lack of ACC on our Bolt is one of the reasons we won't be doing any long distance driving with it. My Prius Prime has it and makes long distance driving such a pleasure. It's even usable in traffic on the HOV lane in So Cal.
 
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