LibrePilot Forum

Users => Vehicles - Helicopters => Topic started by: jairbj on March 31, 2017, 10:31:22 pm

Title: PIDs for a 250 helicopter.
Post by: jairbj on March 31, 2017, 10:31:22 pm
Hi friends, I'm trying to tune my first CC3D Helicopter and it's hard to start (a 250 quad is easier).

Could you share the PIDs you are using in your 250 calss helicopter?
Title: Re: PIDs for a 250 helicopter.
Post by: daveapplemotors on April 01, 2017, 03:23:48 pm
did you see this page?

PIDs are down under "StabilizationSettingsBank1".  'bank2' and 'bank3' also.
Title: Re: PIDs for a 250 helicopter.
Post by: jubjub on April 01, 2017, 07:01:05 pm
I am not sure if this work for you, but for my QAV250 carbon fiber model it worked.
I inform you that the default (factory) PID values were NOT working on my drone, so i had to change them.
You can also use the TxPID and use your 2 knobs on your transmitter to calibrate the PIDs and be able to take off, for example knob 1 = EasyTunePitch, knob 2 = EasyTuneRoll. The Yaw is automatically calculated based on Pitch and Roll combination (i suppose). It worked for me and i am able to fly and take off easily now.

My values are (Stabilization tab => advanced => Bank 1):
  Roll => P = 0.00196, I = 0.00587, D = 0.000026
  Pitch => P = 0.00465, I = 0.01395, D = 0.000063
  Yaw (auto calculated) => P = 0.00496, I = 0.00941, D = 0.000042

Also, reduce your motors max power to 45 - 50%, this helped me, made my quad slow but strong enough to take off slowly, for better handling until i achieve a good balance.
Fly on a grass field in case you drop down the impact will make NO damage.

Hope i was helpful for you.
Happy fly.

Title: Re: PIDs for a 250 helicopter.
Post by: jcg1541 on February 08, 2018, 08:37:47 pm
I can hover my blade 230s in my hotel room with everything default except cyclic Pitch and Roll P gain changed from default 25 to 64.

The problem with the default P is that it is so small that the servo correction actually comes from D derivative , meaning that when you tilt
the heli body, the swinging action generates D that produces a correction, but when the body settles at the tilt angle, there is almost
no first order correction for this tilted angle. So, the result is that the servo arm comes back to neutral while your heli is still out of
level. FlyingboatRCG has the video to show this problem,
Title: Re: PIDs for a 250 helicopter.
Post by: TheOtherCliff on February 08, 2018, 09:26:02 pm
Many people get confused by the small amount of control.  The key is how does it fly.  In the air, that small amount of swash plate motion (or for instance aileron throw on a fixed wing) may be plenty to move it back to where it should be.