# Homework Help: 3d rigid body dynamics

1. Dec 4, 2012

### xzibition8612

1. The problem statement, all variables and given/known data

I just saw the equation R=R'Ω (where ' is dot, or the derivative) in my notes (unorganized obviously), and can't remember what it stands for (rotation matrices?).
Can somebody please tell me what this equations means thanks. I know R is some position vector and Ω is the angular velocity, but I don't get what this equation is saying. Thanks.

2. Relevant equations

3. The attempt at a solution

2. Dec 4, 2012

### cmmcnamara

That seems a little ambiguous without context. Equations of motion are different depending on different coordinate systems used. $R=\dot{R}Ω$ doesn't look familiar to me at all for any coordinate system. Perhaps take a look at one of my professor's course outline pages and see if you can identify what you are talking about possibly. This page from my old professor's website list the vector equations of motion in four different coordinate systems: http://www.csupomona.edu/~padashner/316/GCO/C.Outline-2.pdf

Hope that helps!