that's so cool! what do you do to keep the screw cores from freezing up solid? I've found myself blowing them out, sometimes unsuccessfully to evacuate the ice core.
You are right on the money. We never really solved that problem for cold ice. The fumarolic ice caves we tested in were close to 0C, so it wasn't a problem. But we did a test campaign in a -25C walk-in freezer, and had to use a hot air gun to clear the end effector manually every step. If we got funded to do another version I think we would try to incorporate some kind of heater.