I have always been fascinated with a mechanical iris, so one day I decided to make my own. I found an animated gif online and reverse-engineered the mechanism. Once I was satisfied with my design of the mechanism, I started printing an octagonal box with a rotating interior cylindrical void. I now use the mechanism as storage for my storage (USB drives, SD cards, etc.).
To analyze the mechanism before printing, I used Creo’s 3D mechanism constraints. I created sliders and pivots to model the various parts. By this order of modeling, analyzing, and then printing, I was able to create the design without relying on trial and error. The final design uses small dowel pins as pivot joints and is kept closed through interference fits around the dowel pin in each of the eight corners of the box as shown in the assembly pictures