Dyne's LD-F1 (D-O concept) build

[Dyne]

I've been pondering this droid a while (since the concept pictures were posted).  For the size, I was thinking more in line with BB-8 scale, maybe because of the color scheme.  The neck, lift, and head motions are going to be the trickiest part and what have been holding me back.

We aren't too far off BB-8's bounding box.  This just occupies a lot less volume.

IIRC, BB-8's body is nearly 20 inches in diameter, and about 26 inches tall counting the dome but not the antennae.

With a base at 15 by 20 inches, LD-F1 has a similar footprint.  Then the height is the sum of:

• the head itself (I'm eyeballing at roughly 4.5 to 5 inches without antenna)
  
• the 4 inch height of the tank base
  
• the double piston neck length (8-10 inches judging relative to the base's height)
  

So the top of the head is circa 16.5 - 19 inches high. Here's a size comparison with a roughly BB-8 sized sphere:



On top of that we can add whatever height trigonometry says we can get from the bit of neck that's covered by the panel when at its maximum angle.  I'm figuring on something like a 45-60 degree upper limit.  Too steep an angle will mean the droid risks tipping over (or requires adding weight in the base to prevent that)

I've placed the mid neck hinge 5.5 inches forward of the midline, so the maximum possible length of the lower neck section is 13.5 inches (15.5 for the body aft of that point, minus 2 inches because the cover starts curving around a 4 inch circle directly above the rear axle, so the neck can't protrude further back than that.)

That lower end drops as it rotates backwards around the circle, so you'll lose a bit of height, but the most you'd lose is another two inches if the neck was completely vertical (circle rotated 90 degrees).

This lower neck sizing gives me a maximum head height of 25.46 to 27.96 at 45 degrees (depending on the height of the other parts) and 27.191 to 29.691 at 60 degrees.




As for the mechanism, yeah, it'll be tricky.  I'm still thinking Wall-E might be a good model to use for the lift ... if the mechanism can be adapted.

As shown in Matt's video that I linked in post 1, Wall-E has a linear actuator that pushes a slide at the base of his neck to raise his head.  You can see the movement around 1:40 here to see what I mean about it possibly being a good starting point:





I really need to touch base with Dave Ferreira (who designed that), or look around more on the builders club forum to see if there are any details beyond the blueprints for the external parts.  I suspect he has a parallelogram in the lower neck section and that'll be hard to fit, but maybe not impossible.