Twisted Spiral Problem

Hi! I’m trying to reconstruct the conical spiral ramp of the Meixi Urban Helix structure for a university project. My script defines the spiral curve to gradually increase its radius, like that of the outward slanting vertical support columns. I’ve attached a profile to the base of the curve which I would like to sweep along the conical spiral. However, as you can see in the photo, roughly after the first rotation (blue line), the profile begins to change its orientation and starts to point upwards. I can’t seem to understand why the orientation of the profile is changing and how I can fix this issue so that the position of the profile (selected in green) is the same throughout the entire sweep. I would greatly appreciate your help!

Attached you can fnd a screenshot and the GH file

File ->

Screenshot ->

Thank you in advance!

I’m not sure if I’m allowed to help you with your homework. But since it’s not a big problem and you have made a good effort by your self, I decided to do it.

Conical Spiral (23.3 KB)

Awesome! thanks so much :slight_smile: no worries you can help anytime!