Crimping a stent with a rigid cylinder and equation constraint

[Ciara895]

I am using a rigid cylinder to crimp a covered stent. It works perfectly when I apply the radial displacement directly to the crimper geometry, but I want to get the radial force output from one node. I have tried using an equation constraint but when the crimper makes contact with the stent the elements on the crimper massively distort.

Does anyone have any experience on exactly how to apply the equation constraint?

Thanks

a related thread - thread799-408166

 

[Dave442]

this is what i would do:
[ul]
[li]create a reference point[/li]
[li]create an assembly set using the reference point.[/li]
[li]use *equation to link radial displacement of nodes on crimp surface to radial displacement of reference point.[/li]
[li]specify radial displacement at reference point.[/li]
[li]remember to constrain motion of crimper nodes in circumferential/axial directions.[/li]
[li]request history output at reference point for radial reaction force.[/li]
[li]run your analysis[/li]
[li]plot radial reaction force at reference point to see total radial force during crimp[/li]
[/ul]

this is not necessary though. if you just want total radial crimp force you can just sum the radial components of reaction force at each node on the crimp surface. Using *equation just allows you to skip this summation step.

 

[IceBreakerSours]

I am beginning to forget my Abaqus terminology but you could try using a kinematic constraint, instead. Or, try playing with simple toy models so you can make lots of mistakes quickly and learn.

*********************************************************
Are you new to this forum? If so, please read these FAQs:

http://www.eng-tips.com/faqs.cfm?fid=376

http://www.eng-tips.com/faqs.cfm?fid=1083