Melanie:

I can see two issues in your definition....

1- Your initial mesh doesn't have enough subdivision, so you can increase density with any of weavebird's subdivision tools...

2- Your geometry afected by Kangaroo should be distinct than input parameter mesh as it remains straight instead of elastic... because of not enough subdivition or points.

having this modified you can try different stiffnes, damping, restlength, or plasticity in Kangaroo springs to see what happens

also you could use Kangaroo's springs from mesh to try another way of elastic mesh simulation.

this second approach could give you the possibility of using rest length as a factor of initial lengh instead of a unit value (in springs component restlength values are units)

I'm uploading your definition modified.

Remember I'm a new grasshoper/kangaroo user.. so it's just my point of view.

By the way...check your version of  weavebird, kangaroo and grasshopper to be updated to last available...

I think you have an old weavebird release..

Regards..

Ale

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