I was tasked by my physics teacher to make an unchangeable mechanism that would allow a water balloon to survive drops from 10, 15, 20, and 25 feet while staying in a 1 meter radius circle. I recommend printing the bumpers and gasket out of TPU(95A @10% infill) and the center out of PETG(with as low of layers as you can get, I did 0.12 and 30% infill) while everything else can be PLA @.2 mm layers. I also made a parachute out of some old twine and a plastic bag. to assemble, use threaded inserts in all the holes(M4/M5) I used CNCKitchen's longer variant. I attached 3 rubber bands to the top and 1 to the bottom of each loop. leave a comment if you have any questions

optional: I had a friend CNC me a polycarbonate piece so I could see the balloon without having to take everything apart. totally optional but was definitely very useful, so i totally recommend making either that or using a clear pla or something, otherwise you may just want to print it with whatever else(this is the rounded square).

This design won me best design and was fully successful