Gentlenav VTOL

https://groups.google.com/group/uavdevboard-dev/browse_frm/thread/d88151f4f36e2320

I am excited that you looking at continuing this project. VTOL is a particularly good project to exemplify Bill's approach of not using Euler Angles (with reference to the earth) and of using the Direction Cosine Matrix and Vectors for the computations (avoiding angles). VTOL does the very worst it can to Eulers. It regularly occupies the singularity space of Eulers (Pitch straight up or straight down). I suspect that other projects do use Eulers, and this is one reason why VTOL is not easy for them (or they have to use kludgy logic to avoid the singularity).