How to draw a precise s curve that will meet parallel lines

Hello,

I am trying to draw a series of S curves that will travel back and forth between two parallel lines, like in a webbed truss, but curved (see attached image).
When I try to draw it with control points, there is a lack of precision with the method, and so I cant get the curves to touch the parallel lines perfectly…
I am still new to Rhino, is there a way that I can achieve this (please be descriptive)?

Thanks!

Hello - probably InterpCrv will help here - I’d try that - you may want to make an extra wave or two at each end then Trim or Split or SubCrv to get the bit you want, this to make the end shape consistent with the middle bumps.

-Pascal