Hi Psygorn

Here are ImgBox views of 3 examples:

The first image is a test image for 6 leaves, with 60 degree latitude. The arcLength of half of the (Red) sphereCap * 6, just about equals the arcLength of the Hinge Latitude.
There is no meat to mound a hinge hole.
Curiously, the arcLength of the hinge latitude is 10 * PI. There must be a reason for this?



The second image is at 30 degree Hinge Latitude, with 6 leaves. The neighbor leaf overlaps the hinge area. So a guide slot is likely needed, and the hinge abandoned...



The next image is with 5 leaves, with the latitude circle at 32.23 degrees from the equator. Sphere radius is 10 units.
Hinges have been placed, but no engineering has been done as to strength. This is not a final model, just a mockup.
Using the line from the sphere center, to the center of the hinge pin, as a rotate axis, permits rotation of the leaf.
In a node, six rotation axi, for the 6 leaves, should result in simultaneous opening and closing of the iris(?).



The next image shows the radius of the SphereCap in Red, along with the Hinge Latitude circle. MoI quickly calculates the arc length of each.
The Red length is to be multiplied by 5, to be equal to the Latitude arclength + hinge radius*5.



- Brian