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2016 Prius uses Regen for ABS braking!

Discussion in 'Gen 4 Prius Technical Discussion' started by chughes123, Jan 8, 2017.

  1. chughes123

    chughes123 Junior Member

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    The 2016 Prius really surprised me, in that it definitely was using the electric motor to micromanage the ABS if not doing it entirely in slick conditions at low speeds. I saw the regen bar go to full. I should have tested more to play about the ABS boundary. Maybe if it ices up again tonight. Also to test to see if passive regen (regen if no pedals pressed still happens immediately after ABS activation), because I've long heard the tales of loss of regen when you go over a speed bump. I have a feeling that wouldn't happen with this car.


    I would have thought any EV or hybrid would go to pure brake pad oscillation for ABS. Really nice surprise. Wonder if at higher speeds it'll do that too. I assume not at all with dry pavement ABS of course.
    So question is if that was full electric motor ABS or a blend of the brake pads and regen.

    Regardless, felt very confident. Tires that came with it aren't horrible either, though need to test in pure ice/compacted snow to really tell.

    Anybody know the details of the ABS braking algorithms for the 4th gen?
     
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  2. RCO

    RCO Senior Member

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    Interesting. Do you have a Gen 4 more, as your profile suggests another non-hybrid?
     
  3. chughes123

    chughes123 Junior Member

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    I have this car, and also a 1999 Civic. With goals of a Chevy Volt and/or high end Tesla eventually.
     
  4. Prodigyplace

    Prodigyplace Senior Member

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    What trim level & tires? I have a 2017 Trim Two with Ecopia 442.
     
  5. chughes123

    chughes123 Junior Member

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    Toyo Nanoenergy. I think a '3' but shouldn't make a difference.
     
  6. Prodigyplace

    Prodigyplace Senior Member

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    Thanks. 5 inch tires like my car but different brand. I know people have talked about noise differences with the various tires so I assume there are traction differences too.
    I guess I will find out how mine handles snow & ice this week. It will likely be Tuesday afternoon before temperatures venture above freezing here.

    Keep safe.
     
  7. kithmo

    kithmo Couch Potato

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    My Gen 4 definitely loses traction on regen over rough surfaces, the same as my previous Prius+ and my Gen 3 before that did.
     
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  8. Trollbait

    Trollbait It's a D&D thing

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    Bumps and rough roads could cause a wheel to lose contact with the road surface. if that happens, the braking system might assume things have gone bad, and switches to friction brakes for better stopping.

    I though ABS would modulate the braking between the left and right sides; that's not possible with regen on the Prius. Then there is the issue of the rear brakes. I know most of the braking force is carried by the front brakes, but if conditions are such that ABS activates, I would think you would also want the rear brakes to be used too.
     
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