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Jan21-13, 01:23 AM
P: 19
Quote Quote by haruspex View Post
you can't get that result just by moving faster one way than the other, but you can get it by moving the arms one way while extended and the other while drawn in. It's how cats land on their feet.
I didn't think so. I believe I'm misreading or misunderstanding the source document. It discusses a satellite performing planar motions to defeat an external torque. Perhaps disturbance torque or something, the source doesn't really matter.

Neglecting the modes of the flexible arm, the equation looks like this:

##J\ddot{\theta}+ {\sum}({\rho}\ddot{\theta}qin^2 + 2{\rho}\dot{\theta}qin\dot qin + Jn\ddot qin)##

Where J is the inertia of the hub, Jn is the inertia of the arm, and qin is the motion of the arm. The summation (I'm not versed in Latex) is i=1 to k, I think this is for point mass along the arm.