trouble to draw protein helix

[landmak2]

hello everbody!!!

I need help

I usage this formula to draw helix

http://mathworld.wolfram.com/Helix.html

But I need draw helix in this format with twists and curves along the route

http://www.postyourimage.com/view_image.php?img_id=92mJqL2pHvURq321216910960

This helix have control poinst (Alpha carbon)

how should I proceed?

Thank you for your attention

[pkleinod]

Hello. The attachment contains a sketch of how to proceed. The equations have not yet been checked numerically, so use with caution.