Picking Up Upside-down Totes?

[Deucalion]

For the past couple of days I have been hearing mutterings from my team (STEMpunk 4531), as well as from many here on Chief Delphi concerning the difficulty of picking up an upside-down tote as compared to one found rightside-up. So to put the speculation to rest I ran a few experiments 10-12 times each, and determined quite reliably that at a contact pressure of no less than 6 pounds, any arbitrary end-effector should be able to grip the sides of an upside-down tote so long as the friction coefficient between the surface of said end-effector and the plastic walls of the tote is made equal to or greater than the coefficient between plastic and a pair of sweaty boy hands.

I didn't even need a calculator for this one, but if anyone else has a spread sheet or a graph or something showing exactly what it takes to grip a plastic bin at varying distances and with different materials, I would certainly like to see it, even if I wouldn't necessarily make one myself.

Now, of course there are other problems involved with upside-down totes aside from simply picking them up. For example; How do we flip them right side up for stacking quickly and efficiently, why not stack them all upside down, and how do we get our robot to recognize and accept both orientations in auto or even tele-op are all tricky issues and I would love to hear what you guys have to say about them!