I am trying to find out if gravity plays a role in the value of the vibration frequency of a system. I do studies on a telescope, and whatever the inclination of the main axis (bottom right on the image), inclination that I adjust by changing the direction of gravity, I always come across the same values. Is this normal, or is it Solidworks that is turning gravity? Intuitively, the more inclined the axis, the more the whole thing deforms, the lower the frequency. But I may be making a mistake in my reasoning.
Have you activated the "stress stiffening" in the properties of the study? It seems to me that this is the option that takes into account the loads in the calculation of eigenmodes (to be confirmed).
Your set deforms as long as the bars that hold the top top are slightly soft.
If they are very stiff, it will not change much when leaning.
Without gravity you can put a lateral force (at a distance in a vacuum SW allows it) and in your simulation you will see how much the bars deform.
Your lateral strength must be about the height of the CG of the upper part.
In fact it depends on whether your cg is very high or very low. Is the cg the result of the whole telescope and not only the upper part.
But be careful for the cg you have to neutralize the lower parts. We can discuss the CG because I have a good experience on moving cinematics.
Kind regards
PS: in the case of a telescope the two most important things are stability at standstill and temperature variations which must be banned. The natural frequencies for a system at a standstill don't make much sense, on the other hand if the vibrations come from the ground you can have an amplification at the top (infrasound most of the time unless a fool puts a generator at 5 meters) or from the wind which pushes on the upper part and causes oscillations that are difficult to determine.
EDIT Spelling correction and addition of clarification on vibrations
