Hello,

I am trying to create a generic model for a spring-damper system that is experiencing base excitation. I want the function input to be the position/displacement function rather than a known velocity or acceleration.

I see a lot on here for ODE 45 for differential equations and integrating with a known velocity or acceleration. Is it possible to set it up to go the other way? I was hoping to see if there was a way to do this with ODE 45 instead of now just stating my function as the acceleration. I essentially want to create something that models the force transmitted to a mass from a known input. I thought there would be something already out there, but I just haven't found it yet. I may have just been staring at the problem too long.

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