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Road-rager's attorney mentions regenerative braking during case

Discussion in 'Model S: Driving Dynamics' started by yobigd20, Jan 21, 2016.

  1. yobigd20

    yobigd20 Well-Known Member

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    interesting - Tesla driver pleads guilty in road-rage conflict with Marin cyclist - San Jose Mercury News

    i've always NOT been a fan of the regen causing brake lights to come on, as on the NJTurnpike I get the middle finger a lot from people thinking that I am brake checking them when I am not and they get mad and try to cut you off etc etc (typical jersey driving). I'm not really sure what happened in the above incident, but the guy said he didn't apply the brakes but instead regen came on the brake lights activated and the cyclist crashed into the back of him. his fault of course was driving off after the cyclist hit him (hit & run).
     
  2. Max*

    Max* Autopilot != Autonomous

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    I think it's smart for the brake lights to come on, you're decelerating, the person behind you needs to know. If you want to coast, keep the power meter at 0kw.
     
  3. DDarrow

    DDarrow Member

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    I actually think Tesla does a pretty solid job of determining at what point the regen braking force is enough to activate the brake lights. If you keep an eye on the dash you can see at what point your brake lights activate.

    It does seem that some Tesla (and hybrid) drivers, get a little too aggressive with the use of regen. Keeping a slight amount of pressure on the accelerator is obviously going to reduce the regen level, however it also lengthens the time you're regenerating since you are decelerating for a longer period of time. So ultimately you're getting approximately the same amount of net energy, but doing it without sudden speed changes that are going to irritate other drivers.
     
  4. McRat

    McRat Active Member

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    Regen braking probably had nothing to do with that.

    If you ride a bicycle or motorcycle on public roads, you learn that. A small percentage of car drivers are not good at sharing the road. They do not believe 2 wheelers belong on the roads and they let you know it.

    I'm guessing the driver is that kind of person, and is good with hit-and-run, he most likely lied in court. He probably brake checked the bicycle to make him crash, it probably wasn't his first time, just the first time caught.
     
  5. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    People with non-Teslas activate their brake lights far more than my Model S does.
     
  6. LetsGoFast

    LetsGoFast Active Member

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    A) I'm not sure I believe his story anyhow.
    B) Having the car slow down and not activate the brake light would have just made the situation worse.
     
  7. RedSoxFan18

    RedSoxFan18 Member

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    +1, agree entirely.
     
  8. Zextraterrestrial

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    not sure about the story but I have witnessed some rage when someone thought I was brake checking them. I am really good at keeping just under the brake light limit w/the car image on the dash. just a small indicator would be far better than the car image though - especially for red car owners!
     
  9. AWDtsla

    AWDtsla Active Member

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    I'll say it again. Regen brakes lights are stupid. There's only a very narrow region where the car might slow down faster than engine braking in any car.
     
  10. ICUDoc

    ICUDoc Member

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    Ridiculous claim- that the brake light made the cyclist MORE likely to hit him than if the light didn't come on? Utter rubbish.
    And every Tesla driver should be able to modulate the accelerator to slow exactly as they wish . (Which I think is probably EXACTLY what happened here....)
     
  11. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    On my car it's just the opposite, there is only a very narrow region where regen causes the brake lights to come on.
     
  12. rns-e

    rns-e Member

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    Decelerating at a speed where other cars, bikes or whatever also need to apply brakes in order not to hit you, should always active the brake lights, since that is the very purpose brake lights are on the car for - to warn others behind you that you are decelerating.

    Full regen does not stop the car at a speed where a bike does not have time to avoid hitting you, expect if they are going downhill at 50 mph and you pull in in front of them.
     
  13. GSP

    GSP Member

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    I think you and AWDtsla are talking about the same narrow accelerator pedal region. Where the car slows down faster than normal engine braking is the same region where the brake lights come on.

    GSP
     
  14. DFibRL8R

    DFibRL8R Member

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    How do you know it was your regen braking misinterpreted as brake checking that brought out this oh-so-rare gesture in ...New Jersey. My experience is aggressive hostile drivers can choose any number of perceived offenses to justify their behavior.

    I tend to agree that heavy regen should be enough to trigger the brake light because the car is indeed slowing down. Model S drivers need to be aware of it so they are not sending a signal to other drivers unintentionally.
     
  15. scaesare

    scaesare Active Member

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    Disagree.

    Compared to the 3 other non-EV's in the family, I can decelerate with my Model S without brake lights activating faster than either of the automatic transmission gasoline vehicles. My daughter's manual transmission diesel can about match it on a downshift, but it doesn't noticeably "beat it".

    I'd suggest the vast majority of the cars on the roads don't provide engine braking to a greater extent than possible with regen without brake lights on the S...
     
  16. Max*

    Max* Autopilot != Autonomous

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    She's not downshifting enough ;)


    Hmm... this has me thinking, and I think you're right. Even if I downshifted my previous car to 2nd gear going 60mph, I still think the Model S would have comparable deceleration with me just letting go of the accelerator.
     
  17. scaesare

    scaesare Active Member

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    Hehe...

    I can force it to decelerate faster if I want to crank the RPM way up with each shift... but I was referring to "normal" driving... not the race car experience. :wink:
     
  18. SomeJoe7777

    SomeJoe7777 Marginally-Known Member

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    I'd like to see a small tick mark on the regen side of the power meter that delineates when the brake lights would come on. That way I could modulate the go pedal and stay within the non-brake light region if I wanted.

    As it is now, if I want to do that I have to quickly look from the power meter to the car image in the center of the dash and watch for the (very subtle) brake light indication.
     
  19. Max*

    Max* Autopilot != Autonomous

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    I believe it's speed dependent, so the tic would have to be dynamic.
     
  20. Zextraterrestrial

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    wait, but
    normal driving = race car experience...
     

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