Freefall in color by many folks.
Perth Hillman: Another factor is robots can't do this job. Not all of it. This station was designed and built by humans. There are some areas that are very hard to get to.
Perth Hillman: No robot yet has the physical agility to climb a vertical ladder, worm its way through wire bundles WITHOUT damaging them and then wedge itself between a pipe and a wall in order to troubleshoot a valve.
Sam: Why would anyone put a valve in such a location?
Perth Hillman: Two reasons. It looked good on the prints and the people who put it there knew they would never have to work on it themselves.