I had few days so I integrated the new GPS and created a stand to aid to create a math model of the heli and test control algorithms without any fear of crash (never test control algorithms without previous verification in a safe environment no matter how confident you are about your work – proven by experiments …).
So, here is the stand
It is home made from waste I found around the house but for now it is more than sufficient.
It enables free rotations only around yaw and pitch axis (yaw is without limitations and pitch is limited to +-45 degrees) and is “mounted” at the center of gravity of the helicopter.
It is firm enough to handle 100% engine throttle – which in fact is a bit terrifying. When you see it and feel the wind you realize how powerful and potentially dangerous it is.
I am planning to add rotation around roll axis to have free rotations in all axes but it will need more sophistication and some new tools.