EOMs for T Shaped Pendulum with Non-Conservative Force

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The discussion focuses on deriving equations of motion for a "T" shaped pendulum influenced by non-conservative forces. The system consists of a base mass constrained to move in the x-direction, connected to a linear spring that restores it to the x = 0 position, while friction is neglected. The top mass can rotate around the base, with a torsional spring providing restorative forces to maintain vertical alignment. The user seeks feedback on their virtual work calculations and whether moment-work considerations are necessary. The thread aims to clarify the correct approach to modeling this dynamic system.
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EOMs for "T" Shaped Pendulum with Non-Conservative Force

I have a set of equations of motion I'm trying to derive. This problem represents a 2-d approximation of the real system that I'm trying to derive equations of motion for modeling purposes.

There is a base mass and a top mass.

The base mass is constrained to move only in the x direction and is connected by a linear spring to ground which is meant to produce forces that restore the mass to the x = 0 position. Friction is ignored.

The top mass designated (the "T" shaped pendulum) can rotate about the point at the center of the base coordinate system. A torsional spring is operating on the pendulum to produce forces that restore it to the vertical position.

I've chosen my generalized coordinates to be x (corresponding to x-base) and theta (rotation of pendulum from horizontal).

I will include my derivations in reply to this post but my main question is whether I did the virtual work properly? Do I need to for any sort of moment-work?
 
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