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Active Member
SICAD
Posts: 9
Registered: ‎02-17-2012
Accepted Solution

Unidirectional release

347 Views, 5 Replies
02-20-2012 04:13 AM

Hello,

 

what I'd like to know is:

 

does "Released direction" mean that there is no restraint in that direction?

For example, does released direction Ux+ mean "no restraint in Ux+"?

In the attached sketch you can see my doubt.

Thank you.

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Product Support
Rafal.Gaweda
Posts: 5,204
Registered: ‎04-26-2010

Re: Unidirectional release

02-20-2012 04:40 AM in reply to: SICAD

Take a look at this help topic:

 

http://docs.autodesk.com/RSA/2012/ENU/filesROBOT/GUID-A65C66FB-20DA-4B7C-BFE2-3A7B0CF54F7-249.htm

 

UX+\- shows different direction depending on bar start \ end



Rafal Gaweda
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Active Member
SICAD
Posts: 9
Registered: ‎02-17-2012

Re: Unidirectional release

02-20-2012 05:29 AM in reply to: SICAD

Oh, yes! ... But I think that it is exactly the opposite!

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Rafal.Gaweda
Posts: 5,204
Registered: ‎04-26-2010

Re: Unidirectional release

02-20-2012 06:14 AM in reply to: SICAD

Take a look below, no compression (yellow diagram , Fx force) on right hand side beam due to release Ux+ defined at the beginning of this bar, tension in left bar

 

fx.jpg



Rafal Gaweda
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Active Member
SICAD
Posts: 9
Registered: ‎02-17-2012

Re: Unidirectional release

02-24-2012 12:52 AM in reply to: Rafal.Gaweda

I think the problem is solved:
let's take a look to the central node; the situation should be

Release001.jpg

this means that the 1st node of the 2nd bar is free in Ux+, while the whole bar is free in Ux-.
Due to the fact that there is a DSC element (is it correct?), the node and the bar move in opposite directions.
So the "beginning node of the bar element" (User's guide) is the node 1 of my sketch, while I intended that it was the "new node" of my sketch (they can move in opposite directions).

Giorgio

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Rafal.Gaweda
Posts: 5,204
Registered: ‎04-26-2010

Re: Unidirectional release

02-24-2012 04:11 AM in reply to: SICAD

DSC algorithm creates connections between phisical node (on your screen capture node 1, on mine (below) node 2) and calculation node (on your screen capture "new node", on mine  - node 10).

In our situation (unidirectional realease UX+) such link does not exist between these two nodes only in UX+ direction so node 1 (or 2 on my example) can be displaced but your "new node" (mine node 10) remains in the same position.

 

displ.jpg

 

In case of opposite direction force these nodes will act toghether:

 

displop.jpg



Rafal Gaweda
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