I have a spring that I need to be able to compress and extend. I did a little searching, and I found this tutorial that shows how to animate a spring that was modeled with NURBS curve deformers, but my spring is modeled with the screw tool. I tried to apply my simple rigging knowledge to the problem, but just a simple two bone armature with a stretch to constraint and some scaling constraints on the spring doesn’t work as I’d hoped (and logically so, after some thought.) spring.blend Is there a simple way to accomplish this, or do I have to re-model my spring with NURBS curves?
From just glancing at the tutorial - yes you probably should follow it … unless you want to add a bunch of bones so you can keep the radius of the spring wire itself to be intact … or you could just add a curve (of any flavor) make it coil along your spring and make it be a curve modifier for the mesh and then parent the curve to the stretch to bone … though even with that you won’t get the side to side motion that you can key with the method in the tutorial … but it would be just simpler to modify the very thing that models the spring (the NURBS curve) then mess with adding more modifiers …
You can also use a lattice over your spring. Also, try taking each plane of the lattice that cuts perpendicularly through the spring’s axis and hook each to an empty. If you’re determined to use bones, try hooking those instead of the empties, although I haven’t tried that. You can also use the “slow parent” function to simulate a spring’s movement, if that suits your needs. 3dGuru had some comments on this a long while back. Try searching his threads.
Ok, I’ll just re-model with a NURBS curve. Thanks to this awesome script I found it should be easy! link