This repo contains software required for design and evaluation of a tapered, rotating sling on the Moon, to be made of basalt. The basic idea was presented at ASTRO 2018 in Quebec city on the ISRU track. Here is the slide deck. The submitted paper (draft) was "A rotating, tapered, balanced sling launcher on the Moon made of lunar regolith basalt fiber". There is also this spreadsheet for computing sling mass given sling arm tether material and payload mass.

Included are some POVray sources for generating animations of the sling in operation.

With the .png image sequence generated by POVray, you can use the instructions here

http://www.andrewnoske.com/wiki/Convert_an_image_sequence_to_a_movie

for VirtualDub (Windows) to make a video.