Damped mass spring system with with external forcing function

AI Thread Summary
The discussion focuses on modeling a damped mass spring system influenced by an external sinusoidal forcing function. The user seeks to calculate and plot the mass's motion relative to the system. A suggested approach involves finding both the homogeneous and particular solutions to the system's differential equation. The user specifically aims to understand the steady-state motion of the mass displacement, excluding the amplitude of the forcing function. Clarification is sought on whether the combined solutions will suffice for this analysis.
kstylian
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Hi All,

This is my first post here, and thanks in advance for any help and direction.

I'm trying to model an enclosed damped mass spring system with an external forcing function acting on the system (not on the mass directly). Ultimately I would like to plot/calculate the motion (y) of the mass relative to the system, supposing the forcing function is sinusoidal.

Please see attachment.

Thanks again.
 

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  • Mass Spring System.jpg
    Mass Spring System.jpg
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Is this really as simple as: ??

4bc6ebfe10ca3133701a6761bd5cc324.png
 
yes, now find the homogeneous solution (easy) and the particular solution (guess Acos(wt)+Bsin(wt) and solve for A and B) and add those up.

You can also do this by finding the system's transfer function, but in this case its not worth bothering yourself with that:
http://en.wikipedia.org/wiki/Transfer_function
 
Thanks. I'll try that...

The reason I posted is that I'm interested in steady state motion of the mass displacement relative to the system ONLY...not system + forcing function amplitude.

Will the homogeneous + particular solution provide this, or is there more to it...?

Thanks again!
 
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