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Technical discussion: 2nd row seat design

Discussion in 'Model X: Interior & Exterior' started by scaesare, Oct 1, 2015.

  1. scaesare

    scaesare Active Member

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    I've been thinking about the X 2nd row seats after watching the reveal, in the context of the previous (long) thread that discussed them prior to the launch.

    In that thread it was surmised that Tesla likely had to forego folding seats based on the need for seat belts to be integrated in to the seat structure, rather than the vehicle frame (as a result of the falcon wing doors). Ostensibly ,the forces in a collision would be too great for a folding mechanism to withstand, allowing the seat back to flop forward with the forces of an occupant slamming against the shoulder belt.

    Admittedly, there is a lot of force on the base of a seat back with an adult occupant being slammed forward at several G's in an impact. Assuming the top belt attachment point on the seat back is ~30" from the seat hinge, that's quite a lever acting on that mechanism.

    However, that same belt attachment point is likely ~45" from the seat pedestal base... which does tilt. That's an even longer lever, introducing greater forces acting on that floor articulation point.

    Now certainly, there are packaging considerations, in that designing a mechanism to fit within the area where the seat cushion meets that back may be the significant challenge. But if they were able to design an articulating pedestal base to not fail with the weight of a 250 lb man during a 50MPH frontal impact....

    Thoughts on the engineering or tradeoffs involved? I tend to think the pedestal power tilting mechanism may be a beefy screw-drive on a substantial pivot anchored directly to a chassis cross member. Would a lever-actuated locking mechanism for the seat back have simply been to large to incorporate in to the seats comfortably?
     
  2. Gwgan

    Gwgan Almost a wagon

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    The hing part of the back seats does look a bit hefty and not as elegant as the rest of the seating. I can imagine how reinforcing a hinge at a 90 degree otherwise unsupported lever arm might be even worse (red dot). Would it be less cumbersom to break in the flat of the seat back (green dot)? A hinge there could be at the height of the folded rear seats and the shorter fold part could fit between the rear and front seats.
    hinge diagram.jpeg
     
  3. CHG-ON

    CHG-ON Still in love after all these miles

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    Good point and makes sense. Though too complicated for my small brain.
     
  4. AudubonB

    AudubonB Mild-mannered Moderator Lord Vetinari*

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    As fine a thread-title as any to inject my own query: has anyone looked at how those seats' pedestals are configured, and, as importantly for my own plans, how attached to the deck? Sorry, Tesla: I plan to rip 'em out of my Model X as soon as I get my grubby meathooks on 'em.

    If not all three, then maybe two. Or just one. We'll see...
     

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