dcruze

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Re: Easy Tune???
« Reply #15 on: April 09, 2016, 02:02:21 pm »
Who or what is Dronin?

dcruze

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Re: Easy Tune???
« Reply #16 on: April 09, 2016, 02:06:40 pm »
I found the Dronin Autotunner. I will take a look at it. Thanks

dcruze

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EasyTune Min Max?
« Reply #17 on: April 09, 2016, 02:45:01 pm »
I started this question under post Easy Tune??? and I appreciate the feedback I received, but I don't understand some the answers I received, so I will try and restate my problem.

I am trying to set up a Eachine Racer 250 using EasyTune. I have EasyTune assigned to a rotary knob ona FS_TH9 controller, but where do I get the numbers for the Min and Max settings? I tried flying with numbers I made up and see no difference in the flight.

I read the posts and watch video and people just plug in numbers. Do they make them up or do they come from somewhere? Sorry I keep asking this, but I feel like I am missing a step in setting this up.

Moved: No need to start another thread. Thanks
« Last Edit: April 09, 2016, 02:57:37 pm by f5soh »

Mateusz

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Re: Easy Tune???
« Reply #18 on: April 09, 2016, 02:50:31 pm »
Dronin has a really nice autotune that I used on my ER250. Worked like a champ.

Sent from my iPad using Tapatalk

I would like to strongly emphasize that using Autotune is not a fool prove method to be used blindly and does not under any circumstances remove from user the burned of learning and knowing what PID tunning is and how to perform it or how to inspect obtained PIDs.

Autotune was first developed in OpenPilot, then continued being developed in TauLabs, then forked into dRonin and it improved over time. It was ported "back" to LibrePilot recently and gives same PIDs as dRonin module. However it does not always give optimal PIDs for some of FTT pilots (despite testing with dRonin firmware or LibrePilot firmware), and they prefer to use old school tunning. Sometimes PIDs are just wrong. Additionally, if PIDs are off you might have miro-oscillations and your motors might get hot (like it was in my case with Yaws too high with this module). Of course it can be fixed by changing parameters manually, but you have to understand what are you doing, and you just can't use it blindly.

It's a very nice feature, which I hope will be integrated with LibrePilot soon, but especially with this module, user should really check PIDs before flying them, do they make sense.

dcruze

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Re: Easy Tune???
« Reply #19 on: April 09, 2016, 03:19:58 pm »
I found the Dronin app. It looks just like EasyTune so is there any difference?

dcruze

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Re: Easy Tune???
« Reply #20 on: April 09, 2016, 03:31:55 pm »
I am starting to understand PID's but when I watch videos of people tuning they just start plugging in numbers without showing where they get the information they are using.

I see a advantage to EasyTune to turn a knob and get numbers instead of flying, change number, fly, change number etc.

So where do I get Min Max settings for EasyTune?

Is there a step by step procedure for newbeeies.

I appreciate every ones input, but I have been working on this for days, and it gets very frustrating trying to find the right info.

Mateusz

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Re: Easy Tune???
« Reply #21 on: April 09, 2016, 04:52:49 pm »
I am not an expert but maybe min / max values depend on the properties of the system you are tuning and input/output values.
Here you can read about Starting parameters http://innovativecontrols.com/blog/basics-tuning-pid-loops

The Min of 0.0015 and the Max of 0.0095 are values where most tunings end up. If your PID values are absurdly large or way bigger than what other people tend to get, then you should stay alerted and be careful.

Here is a good video explaining why do you tune PIDs

Also imagine example where process variable (PV) is measured by barometer air pressure, the desired altitude also in the same units as pressure called set point (SP) is known, and the PID controller adjusts output (OP) that is directly affecting the speed of motors and thus generated thrust that lifts up or down the quad-rotor. Now output (OP) affects process variable (PV) and loop is closed. In LibrePilot those PIDs are called VerticalVelocityPIDs and they are used in Altitude Vario or Altitude Hold thrust modes. Other PIDs like inner-loop (which is the loop you should tune) by flying in Altitude mode, are the stabilization PIDs.