For those interested to develop control systems for rotor crafts:

http://johnson-aeronautics.com/documents/CAMRADIIoutline.pdf   

I was told  that the simulation aspect and calculations for the phase-space can be obtained from this software, rather writing my own which is reduntant. 

This took might be quite useful for the community here, since slight alterations to the Arducopter is difficult to debug and maintain. 

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