Frequency content of shock 1

[izax1]

I want to know the frequency content of a saw tooth shock according to MIL-STD-810. Is there an easy way to find this out.

Thanks.

 

[IRstuff]

FFT???

TTFN

FAQ731-376

 

[btrueblood]

Or...as tom will tell you, a SRS may be more what you are looking for...

 

[FeX32]

Of the shock itself? Or of the response of a particular system to the shock? ....

Fe

 

[electricpete]

Or could be a spectrum of responses to infinite number of systems....

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[electricpete]

....As I now understand it that's what SRS is. Plot of peak response of SDOF system to a given base acceleration, plotted as a function of resonant frequency of the system (each point on the plot corresponds to a different system).

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[FeX32]

Yes. Just as in the other thread. Mayby the OP should read that one...

Fe

 

[izax1]

Thanks everybody for the input.

yes, I'm talking about the shock itself. I know the natural frequencies of the system exposed to the shock, and have to consider: Will it be able to withstand a half sine or a T Sawtooth shock better. Same max.level, same duration.

 

[FeX32]

Well it sounds like it's not of the shock itself. SRS may be suitable as electricpete mentioned.

Fe

 

[IRstuff]

If you already know the natural frequencies of the system, then you can model the system as one or more RLC networks, and simply throw the different waveforms at the network and see what the response is. If you have your system in CAD form, then that could be done completely with the CAD system.

TTFN

FAQ731-376

 

[electricpete]

Attached is an excel file that will solve the acceleration response of a SDOF system to an arbitrary acceleration of the base.

Instructions are shown in the instructions tab. Input your arbitrary waveofrm in "input definition" tab, then define your SDOF system natural frequency and damping factor in the "main" tab. Main also has program controls.

The outline of solution method is shown in tab "ProbDefn". The problem is formulated in state space form x' = f(x).

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[izax1]

Thanks alot, electricpete.