This is an interesting piece of tech that gets a fair amount of usage. I think some everyday industrial objects hide a complex mechanical layer and present it as simplicity. To understand this piece, think of the single-use paper towel dispensers inside public toilets. This has been raised this to the next level, providing a continuous textile towel - which possibly gets afterwards washed and repaired - guessing around 50 meters in length. You pull the towel piece facing you, from the top, it allows about 30cm to be drawn out, after ~10 seconds it draws the slack (30 cm) back into the unit. This has to be experienced in order to understand the mechanical clockwork hiding inside. There are no electronics involved here. Fortunately, there was a broken unit waiting for repair, complete with refill instructions. The upper roller supplies the towels. The lower roller is the take-up roller. The green cylinder, spring-loaded, flattens up the take-up so that it's as tig
Electronics and programming interspersed at various levels of difficulty.