Relating pavement roughness in frequency to displacement

[KToal]

Hi all,

I'm attempting to optimise a suspension system's spring and damping rate via vibrational analysis.
Working in the frequency domain, I have calculated the input-output relationship as a ratio (i.e. ground to body, x/q2 in the attachment) and the mean square acceleration response based on an input modeled using an exponential power spectral density.

From here I want to calculate the corresponding stroke of the suspension components and the separation between the road and the suspension system as a measure of road adhesion. My intention is to optimise the k and c values based on these three measures.

So what I'm asking is how do I relate the frequencies I've used in my MSAR calculation to the change in vertical height of the road or vice versa? Or am I going about this in the wrong way?

Attached is the half car model I'm using and the key equations along with my rough spreadsheet used for calculations.

Thanks in advance.

 

[Nidum]

What you are attempting to do has already been done many times over .

Try researching the subject :

https://www.google.co.uk/search?q=a...&oe=utf-8&gws_rd=cr&ei=qlrIVbHwAunX7AbdvJ24Ag

As regards your actual questions I and probably others would be happy to discuss these if you can't find what you need in published material .

 

[KToal]

Thanks for the reply. Perhaps I need to be a bit more specific.

What I'm after is a way of finding q2 or x for a given frequency. So would it be valid to divide the Mean Square Acceleration Response by -omega^2 to get the displacement? I.e. x(f).

I have delved into a considerable amount of the literature but I can't find an adequate answer.