since installing AC 2.5 things are going frankly very well - im not affected by the magnetometer problems and i have been able to get a lot of really good flights in with only very minor problems.
i fly a fairly standard jDrones hexa with 880kv motors and 12x4.5 props (12x3.8 APC on their way). i have recently built a relatively heavy, aluminium landing gear with camera tray, this has increased my all up weight from 1.8kg to something close to 2.0kg and obviously lowered the CG. to get it flying i concentrated on the RATE loop, and ended up with P:0.095 I:0.025 D:0.002, which was certainly not perfect but i could fly it.
i then added 380g of camera, bringing my AUW to between 2.3 and 2.4kg and again lowering the CG quite a lot - this caused a considerable rebound when returning to level. again concentrating on the RATE loop i tuned to P:0.08 I:0.025 D:0.006 which is, in most situations, really _really_ nice and smooth. as long as i maintain steady flight its absolutely great, but it the case of hitting turbulence, or dropping into my prop wash the oscillations are quite pronounced - even scary.
i downloaded marcos heavy X8 config, mainly to try the loiter parameters, and spent a good while last night comparing line by line the differences. what stands out the most is the difference in our STAB values and how they interact with the RATE loop. in my case im flying with STAB P of 4.2 and a very slow RATE P, yet marco has STAB P of 3 and RATE P of 0.14.
in light of this i wonder if i should try the same, lowering my STAB loop and upping the RATE - perhaps i can maintain the excellent, fluid flight in normal conditions and at the same time make it more able to cope with turbulence. i have a few days of landing gear construction ahead of me so wont be flying this weekend (now updated to 2.5.3), can anybody comment on the relationship between these two loops - i was surprised to see such a heavy beast with a rate loop that high and it strikes me that i should try along the same lines.
regards,
james
Replies
Hi James!
I personally work with a fairly low STAB_P because my X8 has a tendency to go too in level flight during turns, working with RATE_P high enough I can have more control and feeling during real flight.
It also depends on what we do with our quad, I make photos and movies and I'd rather be able to work better with the flight stick of pure quad, without the electronic tent too keep it level.