This is a pointless machine. It doesn't do anything but it is fun to play with. The machine converts rotational motion(the handle) into linear motion of the bar in the middle.
Check out my youtube video about it for assembly instructions and some of the iteration I did on the design: https://youtu.be/kA3IxCH6imI
Inspiration for this design was drawn from:
507 mechanical movements #93 slotted yoke - http://507movements.com/mm_093.html
These designs were made in fusion 360, sliced with Ultimaker Cura, and printed on my modded printrbot simple metal.