Missing Reference Point 1

[OptiEng]

I am trying to run an analysis, but I recieve an error message when I submit telling me that the rigid part instances back plate does not have a reference point. However I have defined a reference point (RP-2) to this part with boundary condtions. I have uploaded the cae file. Any input would be much appreciated.

Thanks

 

[rstupplebeen]

I believe that the error is because it wants you to have the whole body in the constraint not just the 1 face.

Why do you have 2 rigid bodies? There will be no deformation.

You are holding the one face of the plate and also applying a pressure to it. The constraint will act as a sink for the load.

When my current job's complete I can try to make these changes and run it here but that might be a while.

I hope this helps.

Rob Stupplebeen

 

[rstupplebeen]

I noticed that you had a rigid plate that the other RB constraint was to. I modified your model removing that rigid plate and also solved it in Standard. I added another step with some rotation. I also added stabilization in the first step to prevent RBM. I hope this helps.


Rob Stupplebeen

 

[OptiEng]

Thank-you so much for your input. I was trying to recreate a problem from 6.9 training manual. I can't see how they set the rotation, I remember from a previous post from you that this is likely to be from an input file which they don't post with their manuals. I have attached there cae file.

Also, they seem to model the problem in explicit and use orphan meshing. Any reasons for this?

Also, sorry does RBM mean Rigid Body motion? Why would we need stablization if we already defined something as a Rigid Body?

Thanks again

OptiEng

 

[rstupplebeen]

I did the rotation in a boundary condition.

This is probably to reduce the file size. I almost always import geometry unless it is simple like a plane or a sphere.

Yup. The break pad could translate in the U1 direction if the contact was not occurring. This removes the issue of an infinitely small force causing an infinite displacement. I use is by default in contact problems and then check if the energies are excessive.

I hope this helps.

Rob Stupplebeen