About natural frequencies
About natural frequencies
(OP)
This is the first time I use the frequency analysis module of Catia. I have performed a normal modes analysis to determine the natural frequencies of the support you see in the next picture

This support will sustain a mass of 600 kg and this mass cannot vibrate, to place this support with its mass I will use precise rails. After the modal analysis the frequencies I obtained were:
5.85242 Hz
22.7846 Hz
38.5786 Hz
52.584 Hz

What frequencies should I compare these with? How can I obtained them?

This support will sustain a mass of 600 kg and this mass cannot vibrate, to place this support with its mass I will use precise rails. After the modal analysis the frequencies I obtained were:
5.85242 Hz
22.7846 Hz
38.5786 Hz
52.584 Hz

What frequencies should I compare these with? How can I obtained them?





RE: About natural frequencies
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RE: About natural frequencies
Examples would be: attached motors (what rpm do they run at?), vibration from the floor or building columns.
I would also consider, if you haven't already, the pendulum effect frequency of the mass and the torsional stiffness of the bracket, to make sure they don't coincide.
RE: About natural frequencies
RE: About natural frequencies
For what it's worth, and to add to Tmoose's concern, a 4in thick, 40in wide, and 160" long beam (roughly the dimensions of your part, as per the drawing), made of steel, will deflect about 1/4 of an inch simply supported if the end load is 1300 lbm. With a simple point mass assumption (IE that all of the mass resides at the tip of the cantilever), the natural frequency of that beam in the vertical direction is in the ballpark of 6Hz. In other words, it is far from infinitely stiff.
RE: About natural frequencies
You have to tell us what frequencies "you" are worried about. It's your part. Does your mass vibrate or is there a dynamic load (shock) that you are concerned with? The Fn is a good place to start, but we also have to know the response.
Tobalcane
"If you avoid failure, you also avoid success."