Author Topic: Question about Quadcopter PID Control.  (Read 717 times)

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Offline ammjyTopic starter

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Question about Quadcopter PID Control.
« on: October 23, 2019, 06:38:29 pm »
Hello, EEVBlog peoples.

Thanks you for your time.

Now, to design my own Quadcopter simulink model, I am studying one model that I have found in Github.

About it I have a few questions.

first, Please see the attached 1-st and 2-nd screenshot. The developer of this model have made PID controller as follows.

Still I am not sure why developer have connect P(Angular Velocity) with "D" controller.

and also at same time I don't understand why developer have used P signal for D controller.
(I guess P should be needed connect with D controller to make connected result between each dynamics channels such as PQR PhiThetaPsi UVW XYZ 12 states.
but, I am not sure about it...)




and my second Curios is Correction circuit part. Please, see the 3-rd screenshot.

PID controller of this model making 4 output signals, "Phi, Theta, Psi, Altitude" like this from the Inputs.

and this model convert that 4 output signals to 4 RPM signal with this correction circuit after PID controller.

I fully understand why this correction circuit is needed.
but, I can't make definite mathematical base about it.
I can just use this circuit and equation(right side) for my own model. but, minimum I want build some mathmatical clue in my brain.

If you don't mind, Could you give some clues for it ?

Please, let me know.
Thanks you for reading it !
« Last Edit: October 24, 2019, 02:01:16 pm by ammjy »
 

Offline pwlps

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Re: Question about Quadcopter PID Control.
« Reply #1 on: October 24, 2019, 12:28:52 pm »

Still I am not sure why developer have connect P(Angular Velocity) with "D" controller.


The angular velocity is the time derivative of the angle, so it is normal to use it as the derivative term of the PID.
« Last Edit: October 24, 2019, 12:32:34 pm by pwlps »
 
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Offline ammjyTopic starter

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Re: Question about Quadcopter PID Control.
« Reply #2 on: October 24, 2019, 01:58:48 pm »
Thanks you for your time, Mr. Pwlps !

oh yes.. I missed that point during looking up clue of it.

Thanks you !
 


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