Rocket pitch and yaw control question : is is decoupled from roll control?

[DanyloMalyuta]

Hello,

I'm designing a controller for rocket Pitch and Yaw control (aim is for rocket to remain upright, so zero pitch and yaw angles). I'm having trouble developing the dynamic equations and can't find existing material corresponding to my needs elsewhere. I've got the following non-linear dynamic equations:

I'm trying to get a transfer function so I need to linearize these. This is where my problem comes in.

The actuator that I will implement will be unable to roll-stabilize the rocket so the rocket is free to spin, and I want pitch and yaw angles to remain 0==> ψ=0 and θ=0. The problem is then that if I linearize around an equilibrium position where roll angle φ=0 and roll rate P=0, then the linear set of equation that I get is:

These contain no information about roll! Can you confirm that effectively pitch and yaw control is decoupled roll control in rockets?

Best,

Danylo.

 

[WKTaylor]

Alphabet...

You might find these useful, this topic..

MIL-HDBK-762 DESIGN OF AERODYNAMICALLY STABILIZED FREE ROCKETS

http://quicksearch.dla.mil/

AIAA ARC may have downloadable tech reports on [AIAA Journal, papers, etc] articles on Missile stability

http://arc.aiaa.org/action/doSearch?AllField=

AIAA Education Series

http://arc.aiaa.org/series/4.es

Regards, Wil Taylor

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