Grasshopper

algorithmic modeling for Rhino

# writing a function, clothoid

Hi there, I was wondering if I could get some help with this.

I have the parametric formula of a clothoid:

{ Integrate[ Sin[(x^2)/2], {x,0,t}],Integrate

[Cos[(x^2)/2], {x,0,t}] }

or an eural loop (see image attached)

but I'm not able to write either of them well in the function/expression component of grasshopper, and cant get something to draw it! Any thoughts?? Thanks in advance for any help on this

Views: 1894

Attachments:

### Replies to This Discussion

hi andrew

you have to write a routine to perform the integral .search for quadrature on google.

basically the integral is converted to a sum of terms so you need to write a small script

gerry

Gerry thanks for taking the time to reply. It's been helpfull, but I have no experience on scripting, and terrible in maths! do you have an example I can see just to learn quicker??

Hi,

I thing you should check Mårten Nettelbladt's blog for inspiration on clothoids: http://thegeometryofbending.blogspot.se/

Not only Julijonas Urbonas' Euthanasia Coaster, but all modern looping roller coasters use the clothoid shape for a pleasant thrill.

What are you going to use the clothoid for?

The blog looks awesome. I'm doing some research on highways and need to figure out a way to parametrically control the clothoids used in highways.

Could this be of any help?

wow that does the trick, it looks amazing and clever

Thank you Ola!

Apparently I have this from 2009 (I updated a couple of components so it works on the latest release). I have no idea from where I got the code for the fresnel integral, I don't know who to credit.

Attachments:

I probably got it from here: http://www.alglib.net

It says Copyright 1984, 1987, 1989, 2000 by Stephen L. Moshier

Thanks for the reply Vincent, I'm going to get inside the script to learn how it works (while learning how to script)!

by Fernando

by Fernando

• View All