Help with generating a grasshopper script

Hello Everyone! 

I need some assistance with a grasshopper script I am lost on how I can create this script. Basically I want it to resemble this image. I am thinking of using a piping command and a kangaroo component to relax the bottom half of the area and I can control the size of the object, moving it up down or applying different size objects to it like a box, sphere or a plane and that will change the outcome of the relaxed bottom half of the piping. I would really appreciate any help on this. Thank you all in advance!