Danger, Will Robinson...
Actually, from what I could see, it looked like a really tall trash can with holes in each side, and he was cutting a coil of A/C flexduct into long pieces, like they were to put into the holes for arm and leg coverings.
I just came back from the woods-it is starting to rain-and saw the contraption, whatever it is sitting on the patio. He is mowing the lawn (again)-drizzle is falling, but he has got to get rid of the little bit of grass that has managed to grow since last weekend before it pours...