Hi Brett --

Nice to hear from you again.

I have constructed a 1:1 model of the STS-1 leaf spring, based on the
sketch in the paper referenced by Sean-Thomas.  By the way, I can send
electronic copies of the article to anyone that wants them.  I have done
testing with several variations in dimensions and don't see any significant
"zero length" effect (which, incidentally, I think might be more properly
termed infinite length).

I did see the many spring attachment screws in the photo in the paper, but
I don't know how that works.  Sean-Thomas, do you think they adjust the
moment imparted to the spring at the attachment point?

I was rather disappointed that the spring showed no zero-length effects,
and have gone in the direction of investigating period-lengthening
over-center auxillary springs.  This seems promising, but kludgey.

I am very interested in any changes I might try on the prototype that could
improve its performance.  I'd be happy to do any tests.

Karl


At 01:52 PM 3/22/2000 -0500, you wrote:
>To the hardware folks,
>
>Does anyone have any mechanical specs, dimensions or operation/service 
>manuals for the Streckeisen STS-1 vertical?  I recently finished up the 
>preliminary analysis work on the fixed-end leaf spring like it uses, and 
>would like to try out some calculations with data that's a little better 
>than my guesses of its dimensions, etc.
>
>Also what I'd like to find out are things like how they attach their LVDT 
>and forcing coils to the boom.  With flexures? Rigid connection?  And what 
>are the effective mass, spring dimensions and thickness, etc.  Info on 
>their adjustment procedures would also help figure out some of the details.
>
>I'd be happy to pay for copies and postage for whatever anyone has.
>
>The side-plate boom design with a fixed-end spring looks like an 
>interesting approach that might not be too hard to build if the spring 
>analysis proves to work out OK.

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