Hi,
I've flied Y6 & Tri since 2.1 till latest version. I always set D of Pitch & Roll to 0 as I see its the best damping value for my kits. My copters flies well. Just curious, anybody here flies with zero-D like me, and do I miss something if I always go with zero-D?
Tks!
Is there sth wrong with zero D (Pitch & Roll)?
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Lecostarius
- Posts: 46
- Joined: Mon Oct 20, 2014 11:29 pm
Re: Is there sth wrong with zero D (Pitch & Roll)?
I did a logging of the Gyro values inflight and found that for the default values of D, the motor PWM signals are sometimes dominated by D response, probably due to noise with the Gyros (probably vibrations, I guess). That D induces control signal is very spiky. Therefore I reduced D to very little (5) and then to zero. Works great.
So, now I am flying with D=0 just like you do (and sometimes D=2, but hardly ever more than D=5)
Cheers, Leco
So, now I am flying with D=0 just like you do (and sometimes D=2, but hardly ever more than D=5)
Cheers, Leco
Re: Is there sth wrong with zero D (Pitch & Roll)?
Good to hear that, Lecos 
Re: Is there sth wrong with zero D (Pitch & Roll)?
P and I are stock or did you guys set them up to best suite your machines?
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Lecostarius
- Posts: 46
- Joined: Mon Oct 20, 2014 11:29 pm
Re: Is there sth wrong with zero D (Pitch & Roll)?
Well, I tried to optimize them.
It is embarassing to say, but I do not notice -probably due to a lack of flying experience- a huge difference in performance between P values as long as they are in the range between 2 and 10 or so. Less than 2 or more than 10 is pretty bad though. The response gets "stiffer" for larger values inside my "good" range, but I can fly with all values in the range.
The drawback of large values is that in full throttle, single motors will overshoot over max PWM value of 2000 more strongly due to noise, which will push down the other motors and hence reduce maximum acceleration. So I have to compromise between stiff flying and less max acceleration - this is how I set my P value (I think it is 5.0 now).
For I, value, I tried a bit, but then kept the original ratio between P and I as suggested by the defaults, which seemed OK.
It is embarassing to say, but I do not notice -probably due to a lack of flying experience- a huge difference in performance between P values as long as they are in the range between 2 and 10 or so. Less than 2 or more than 10 is pretty bad though. The response gets "stiffer" for larger values inside my "good" range, but I can fly with all values in the range.
The drawback of large values is that in full throttle, single motors will overshoot over max PWM value of 2000 more strongly due to noise, which will push down the other motors and hence reduce maximum acceleration. So I have to compromise between stiff flying and less max acceleration - this is how I set my P value (I think it is 5.0 now).
For I, value, I tried a bit, but then kept the original ratio between P and I as suggested by the defaults, which seemed OK.
Re: Is there sth wrong with zero D (Pitch & Roll)?
Leo wrote:P and I are stock or did you guys set them up to best suite your machines?
Yes we're talking about PID tuning, ofcourse P & I are tuned to personal flying style, as P & I are easier to tune than D. But zero or near zero D we see that the machine is most stable
Re: Is there sth wrong with zero D (Pitch & Roll)?
My experience is the same when upgraded to 6s and 380kv motors... for some reason even with perfectly balanced props i had strange oscillations and behavior... When i was holding it with my hand i could feel some kind of resonance which i couldn't explain as every single motor was turning very quiet from vibrations... So trying PIDs, found that with D set to zero all these "noises" were just disappeared!!!! I had also the same question if there is something wrong to fly with D set to zero, but other than that the control of my craft seemed the same.. still testing...
thanks
thanks