Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Damped mass spring system with with external forcing function

  1. Jan 14, 2012 #1
    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.

    Attached Files:

  2. jcsd
  3. Jan 15, 2012 #2
    Is this really as simple as: ??

  4. Jan 15, 2012 #3
    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:
  5. Jan 15, 2012 #4
    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!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook