The idea of a continuous loop is a good one, then users could just hold on to the rope until they get to the position they want and let go. For single users I'd need to figure out how to wire up a remote control for the power drill.
I'm planning to use my Rollgliss R500 to get myself and others back up a 200' backyard zipline. Currently someone has to be pulled all the way back to the top (in a tree), I'm hoping this will let people get themselves back up to the start so they can just release and zip line over and over. See...
Hi Burrapeg, I just purchased a Rollgliss R500 on ebay: https://www.ebay.com/itm/143177649662
Question for you: how did you get the manual handle off and replace it with a drill?