# EOMs for T Shaped Pendulum with Non-Conservative Force

1. Dec 16, 2008

### bcarlson

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?

2. Dec 16, 2008

### bcarlson

Re: EOMs for "T" Shaped Pendulum with Non-Conservative Force

System Figures

#### Attached Files:

File size:
19.5 KB
Views:
223
• ###### TShapedPendulumMovment_Vectors.png
File size:
14.4 KB
Views:
233
3. Dec 16, 2008

### bcarlson

Re: EOMs for "T" Shaped Pendulum with Non-Conservative Force

Pages 1 through 3

#### Attached Files:

File size:
44.3 KB
Views:
208
File size:
18.5 KB
Views:
226
• ###### 2DStrikerMovementEquationDerivation_page3.png
File size:
46 KB
Views:
204
4. Dec 16, 2008

### bcarlson

Re: EOMs for "T" Shaped Pendulum with Non-Conservative Force

Pages 4 through 5

File size:
58.8 KB
Views:
191
File size:
45.2 KB
Views:
188