Conex size (specifically height) does however affect stacking ability, and I really really wanted to be able to stack three containers. Which is possible, just requires a long (and strong) arm.
But the end result is not only impressive, it meets the stamp of approval:
Two seconds, I tell ya. I turn away for TWO SECONDS to grab the camera and FOOP, up she jumps. Amazing it didn't all come tumbling down, but she is the most nimble of the the lot despite being the largest.
Unfortunately, I couldn't sort a way to make the arm telescope, or have the grabber move up and down on the arm, and still retain enough strength to safely hold stuff. The big container is like 6 pounds empty, and more than a bit unwieldy. After a few months of being totally unable to store this machine properly, I had an epiphany that the end could be removable, which makes the thing infinitely easier to handle. Basically cut off the end and printed up a socket for it:
with a set of plugs for power, lighting, and an Arduino up top. A further epiphany occurred shortly thereafter, which was the ability to have multiple heads, for instance a traditional crane:
I was debating also doing a high-lift fork, but (1) the arm is really far off the ground, so the mechanism woulda been kludgy, and (2) I have a fork already, so designing one wasn't shiny or exciting.
With some of Actuonix's longest/strongest actuators, the arm has tons of power and a good reach:
and the crane has decent lifting power:
