Known simplifications in ACD geometry
- Curve and outer vertical volume of top tiles in columns 0 and
4 is ignored. Instead, xml description simply has a box of thickness
(z-dimension) 10 mm and x-extent = true x-extent of 355 mm.
One could add an additional box for each such tile which would more
or less be the projection of the vertical volume onto a plane perpendicular
to the x-axis. The geometry would be simple enough to add, but we'd
also need to add another field to tile identifiers for "segment" since
some tiles would now consist of two pieces.
- Slant in side tiles is ignored. All side tiles in a given face will
be aligned in the same plane, perpendicular to either x- or y-axis, depending
on face. Vertical dimensions will be adjusted for
the two middle rows so that there is no overlap but also no gap.
- Face sheets for the top and side supports will have the same long
(non-thickness) dimensions as the corresponding core volumes, even though
the 3-d model shows small differences.
- Old value for ribbon thickness (4.5mm) changed somewhat arbitrarily
to 2.5mm since thicker ribbons wouldn't fit between top and side tiles.
Awaiting accurate number from ACD folk (haven't found a way to get it
out of the model).
- Reduce old value of ribbonGap (2.5 mm) to 0.5 mm for minimum distance between
ribbon and a tile since can't make things fit with the larger gap.
(Model apparently has top edge of ribbon
immediately adjacent to bottom edge of top tile with no gap whatsoever.)
- Ribbons which "measure X" (in a plane perp. to X axis) will be modeled
as 3 segments: one along the top face and one along each of the sides
perp. to the Y-axis. Ribbons which measure Y will be modeled as 7 pieces:
one for each affected side and 5 across the top, since different parts
of these ribbons are at different Z. Or, perhaps 9 pieces. Might need
two pieces along each side: one inside the ACDTop volume and one below.
- The only components included in this draft of the model will be:
- The 89 tiles
- The 8 ribbons, segmented as described above
- Top and side supports, each consisting of a core volume and two
face sheets.
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J. Bogart
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