Model a compression spring that moves

[tjstephens]

Hi,

I've modeled a system that contains a slider and compression spring. My model includes a contact set that allows a pin and slot to retain the slider within an outer body, but now I'd like to be able to animate the assembly to see how the spring moves. 

My spring was created with the revolve profile command, so I have access to the parameters that define that, and can modify the overall length to simulate compressing the spring.

Is there a way to get at either:

1) The distance between two faces programmatically so that I can then set the spring length based on that value

2) Find how far a slider joint has moved from its rest position so I can use that to set the spring length

 Thanks,

Tim

[Anonymous]

Hi Tim, in Fusion 360 assembly animations are done by way of joints, and there is currently no flexing type joint as you would likely need for a spring.  I think the best you could do is a slider joint and just ignore the spring for now. 

By the way I'm curious how you made a compression spring using the revolve tool!  Since from my understanding it can only revolve a profile at a single elevation, not an advancing elevation like a helix. 

Jesse

[JFKANSAS]

Probably easier to use the Coil tool to do a Spring anyway. 

[tjstephens]

Durr. Yes, that's what I used.

[ScottWertel]

I don't have Fusion loaded on this machine to be able to describe the technique, but there is a specific modeling technique for compression springs to make them function for rendering.  It's not something you'd want to do for an end-item design package.

In short, you break up each coil into 180deg segments.  Then, assemble them together with the proper connections and planar alignments.

Here's a video on how to do it in Solid Edge.  Obviously the commands will be different, but the technique is the same.

https://www.youtube.com/watch?v=TolbV-dZHrc&feature=youtu.be

[Anonymous]

Yep, that's a very cool idea for animation!

Jesse

[tjstephens]

It is a neat idea for animation, but I'd rather not have to make multiple components in a subassembly to have to do this. I've created a feature request in the ideaStation, which is here (http://forums.autodesk.com/t5/fusion-360-ideastation-request-a/access-to-joint-positions-as-paramete... ) Please vote for it if you think it would be useful.