vibration analysis / tuning

Hi Everybody,

Very much enjoying the capabilities of rhino/grasshopper/large cnc milling machine.

I just finished a piece out of 6061 aluminum. And, a pleasant surprise, the piece generates a very nice ring tone (like a bell) when struck - with a sustain of almost 30 seconds.

So, now I am curious, how to 'tune' the bell, at least for a major harmonic. IS anyone aware of work in this area, using grasshopper, or rhino, or whatever, to model the musical tone of a physical model?

Replies to This Discussion

Permalink Reply by David Rutten on May 8, 2015 at 10:22am

A cursory internet search leads me to believe it is ridiculously difficult to simulate bell sounds based on shape and material properties (and impact characteristics).

Permalink Reply by mark zirinsky on May 8, 2015 at 11:56am

Thanks David. Well, could do a) 'pendulum' ringing around a cross sectional area about centroid, b) reflectance analysis off of air/material interface (like an optical refractive index calculation for transparent materials), probably a few other approaches, but heck, I don't want to do a masters thesis, just tune a few sculptures.

Perhaps I need to do a more modest approach, trial and error and scaling. I.e, if a model 6" long gives a freeuncy of 4000 HZ, and a 9" model give a frequency of 3500 Hz, then to get 3200 Hz we need a size of y. hmmm.

Anyway, great tool - my application is trivial, i.e., tuning a few bells, who cares. but other applications, standing wave analysis in trusses ala galloping girdie, wind induced vibrations in panelized domes, and others, perhaps aren't so trivial.

So, perhaps one of the group will have an idea.

RSS