RigidBody Issue

Altair Forum User

Hi, 

 

I have a wired issue (see image): I apply a rigid body to the upper surface with a master node in the center or rotation (COR). I then apply a moment in XX to the master node. I further constraint the master node so that it only has one DOF around the X-axis. However, the result is not a bending motion but rather a minimal torsion without much moving. I tried a whole punch of settings and it never really works. Is there an issue with the RigidBody?

 

Thanks in advance!

 

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Altair Forum User

Hi,

In the boundary condition applied on the master node, can you uncheck the rotation in X direction and try running?.

Altair Forum User

I tried that and had the same issue. However, the reason might was that I used an Rbody instead of an RBE2? Could that be the reason (because now it works)? I thought the only difference is that one can associate mass and inertia to a Rbody but the function stays the same. Could you explain me why this might cause an issue? 

 

Thanks for your support! 

Altair Forum User

Hi,

This seems bit strange. In RADIOSS both RBODY and RBE2 element types are same. So, changing the element type here will not make any effect in the results.

If you can share the model files (both model files, RBODY and RBE2) we will check and update you.

 

gopal_rathore

Hi,

Both RBE2 and RBE3 do act as same element in terms of stiffness but in rbody the option of ICoG (from 1 to 4) along with mass and inertia can change the behaviour. 

Have you tried the same with ICoG:3 for the rbody on which you were applying moment.