Learning Forum

[Muhammadkhizer]

Structure as Assembling and Dismantling Mechanism

1. Top ring
2. Bottom ring
3. Columns with hinge connection( all three rotation free) along the circumferential direction are attached to the top and bottom ring.

Refer to the image for more detail. A rotation is applied to the top ring. With that top ring will rotate and move up. Consider a cup of a bottle. As columns are attached to the top ring as a hinge connection they will move as well.

[peteroznewman]

Isn't the bottom ring supposed to be fixed to ground in some way? That will give you a much higher first modal frequency.
The rule of thumb is to choose a transient time increment that is 1/20 of the period of the highest model frequency of interest.