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FSD with “AC induction motor”

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I just installed build 2022.4.5 and noticed Tesla did not implement the “Regenerative Breaking in Autopilot” for “AC induction motor”. This motor is fully capable of using Regenerative Breaking but is badly slamming the brakes 50 yards from stopping. Does anyone testing FSD with “AC induction motor” can confirm if it is still totally relying on brakes or if it is offering a more pleasant gradual stopping experience.
 
I just installed build 2022.4.5 and noticed Tesla did not implement the “Regenerative Breaking in Autopilot” for “AC induction motor”. This motor is fully capable of using Regenerative Breaking but is badly slamming the brakes 50 yards from stopping. Does anyone testing FSD with “AC induction motor” can confirm if it is still totally relying on brakes or if it is offering a more pleasant gradual stopping experience.
BTW, helpful if you put your model in your sig.
So did it happen in multiple instances?
What FW were on you before where it behaved differently?
I'm on 2022.4 and my recent drives seemed normal.

Ye4xetR.jpg
 
BTW, helpful if you put your model in your sig.
So did it happen in multiple instances?
What FW were on you before where it behaved differently?
I'm on 2022.4 and my recent drives seemed normal.

Ye4xetR.jpg
Yes, good idea to add the model in my signature. I am talking about a 2017 model X 100d. I noticed that the 2022.4.5 release note did not include the “Regenerative Breaking in Autopilot”. I am assuming this is because those cars did not have Permanent Magnet motors. Since we are still not eligible for FSD in Canada, I just wanted to make sure we will not be stuck with the same behavior as the Autopilot where the car is maintaining speed until it jams the brakes about 50 yards from a stop sign (very annoying).
 
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Additional details helps with the analysis. I have a 2017 X 100D too.

So did it happen in multiple instances?
What FW were on you before where it behaved differently?
I did not yet try this build with Autopilot in a stop and go situation. I just noticed the “Regenerative Breaking in Autopilot” feature was not included. The last time I used Autopilot, it would detect a stop sign at 200 yards but will maintain speed and jam the brakes at about 50 yards. I understand Autopilot is not designed for city driving and I am ready to wait until FSD is available in my region. The purpose of my question was to know if FSD on cars equipped with “AC induction motor” is taking advantage of the regeneration and is providing a smoother slowdown.
 
The last time I used Autopilot, it would detect a stop sign at 200 yards but will maintain speed and jam the brakes at about 50 yards.
Did it happen at mulitple stop signs? Meaning are you 100% sure that it consistently at various (multiple) stop signs (or lights) did not use regenative brakes? It sounds like it happened once at one sign?

I think if that REALLY was true the forum and twitter would have lit up that regenative braking stopped working. Stop signs are not only recognized by vision but also by navigation data maps (because they can be around a corner, blocked by tree leaves, etc).

What FW were on you before where it behaved differently? I'm on 2022.4 and it definitely is using regen braking.

2022.4.5 is a wide release so it doesn't seem like there are any bugs and nothing significant like regen changes on 'legacy' cars with induction motors.

B6zUQHh.jpg
 
I think OP is referring to this item from the release notes. Not a regression in normal regen braking behavior. It's supposed to be smoother.

Regenerative Braking in Autopilot

Autopilot will now use more regenerative braking at low speeds for higher efficiency and an improved driving experience, especially in stop-and-go traffic. Increased use of regenerative braking results in less brake pedal noise and smoother stops.
I updated to 2022.4.5 yesterday on our P100D and can confirm it looks like the pre-Raven cars are not getting this improvement. It was not in the release notes and driving on AP it does not use any more regen and still uses brakes more than it should. Bummer.
 
I think OP is referring to this item from the release notes. Not a regression in normal regen braking behavior. It's supposed to be smoother.


I updated to 2022.4.5 yesterday on our P100D and can confirm it looks like the pre-Raven cars are not getting this improvement. It was not in the release notes and driving on AP it does not use any more regen and still uses brakes more than it should. Bummer.
Thank you for confirming my assumption. Now we just need somebody with a pre-Raven cars testing the FSD beta to see if it performs better. It would be extremely BAD if FSD is also applying very aggressive breaking as it will be almost unusable in city driving situations.
 
I think OP is referring to this item from the release notes. Not a regression in normal regen braking behavior. It's supposed to be smoother.
I updated to 2022.4.5 yesterday on our P100D and can confirm it looks like the pre-Raven cars are not getting this improvement. It was not in the release notes and driving on AP it does not use any more regen and still uses brakes more than it should. Bummer.
Oh, thank you for clarifying that. Now I understand.

Our legacy S/Xs also can't do complete one-pedal driving to a stop (ala "hold" mode). That is a technical feature/function of permanent motors.
Early vs late 2019 Xs had or did not have "hold" mode because of this. See: Anyone know why “Hold” mode not available on 2019 X?

Ye4xetR.jpg
 
Our 6/17 x100d has a hold mode, you just have to step on the brake. Our 3 goes into hold automatically
Same for my 6/17 X 100D ... the difference is with the permanent magnet motors is that they can regen to a stop and automatically goes to Hold Mode.
Our induction motors only go down to a few miles per hour then we have to apply the brake to stop. Pressing harder puts it into Hold Mode.
 
Thank you for confirming my assumption. Now we just need somebody with a pre-Raven cars testing the FSD beta to see if it performs better. It would be extremely BAD if FSD is also applying very aggressive breaking as it will be almost unusable in city driving situations.

I can't speak for a Model X but I am a FSD Beta tester with my 2019 S 100D (pre-Raven). I can tell you the behavior at traffic signals and stop signs is significantly improved with the beta and feels more "normal". Case in point, prior to the FSD beta, there was one traffic light in particular that my car would come up to at highway speeds (highway with traffic signals) and slam on the brakes just before the light which would cause quite a bit of cheek clenching for me.

With the FSD beta, it's a much more gradual stop although I don't think it's using regen - just a more natural stopping distance. Also (off topic), FSD beta properly continues through green lights and resumes when a red turns green with no intervention.

It's not perfect by any means but it is better than the older FSD stack by a long shot.
 
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I am assuming this is because those cars did not have Permanent Magnet motors. Since we are still not eligible for FSD in Canada, I just wanted to make sure we will not be stuck with the same behavior as the Autopilot where the car is maintaining speed until it jams the brakes about 50 yards from a stop sign (very annoying).
The braking profile isnt related to the method used by the car to brake .. just like a human the car can brake gradually or abruptly using either regen or regular brakes. Any jerkiness is related to the way FSD uses the brakes.
 
Thank you for confirming my assumption. Now we just need somebody with a pre-Raven cars testing the FSD beta to see if it performs better. It would be extremely BAD if FSD is also applying very aggressive breaking as it will be almost unusable in city driving situations.
Regen is graphically displayed on the ICD if the energy graph setting is used. All appears normal on my 2018 X. The only time regen is not used, is if the car is very cold, also normal.
 
I can't speak for a Model X but I am a FSD Beta tester with my 2019 S 100D (pre-Raven). I can tell you the behavior at traffic signals and stop signs is significantly improved with the beta and feels more "normal". Case in point, prior to the FSD beta, there was one traffic light in particular that my car would come up to at highway speeds (highway with traffic signals) and slam on the brakes just before the light which would cause quite a bit of cheek clenching for me.

With the FSD beta, it's a much more gradual stop although I don't think it's using regen - just a more natural stopping distance. Also (off topic), FSD beta properly continues through green lights and resumes when a red turns green with no intervention.

It's not perfect by any means but it is better than the older FSD stack by a long shot.
Thank you for your feedback. This is very encouraging as the current Autopilot behavior would make FSD almost unusable. Since Tesla plan to merge both together, I can only wish Autopilot stopping will also become more natural. As for using regen, I also hope Tesla will make some improvements as, with the weight of those cars, I am concerned having to replace brake pads every six months. Those motors are fully capable of slowing down cars. I am using regen for all my stopping and only apply the brakes when a complete stop is needed.