LibrePilot Forum
General Category => General Discussion => Topic started by: dcruze on April 05, 2016, 07:25:54 pm
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I am setting up a Eachine Racer 250. I have loaded Libre Pilot and have it bound to my transmitter. It will fly but drifts and is hard to hover steady. I keep seeing people talk about PID settings and Easy Tune.
If Easy Tune is what I need I cannot find step by step instructions.
How do I tune the Quad to get it to hover. Any help and direction is much appreciated. Thanks
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Try this settings as base:
http://wikirotors.com/index.php?title=Eachine_Racer_250#PIDS
If you are using PWM as input you can just use one Accessory at a time. Need a knob or slider in your radio.
https://librepilot.atlassian.net/wiki/display/LPDOC/TxPID
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Another user posted his uav config file for a stock eachine racer 250 in https://forum.librepilot.org/index.php?topic=1123.msg8189#msg8189 You might try using it as a starting point, he also posted a video of him flying with those settings.
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Thanks everyone, this is very confusing.
HWH, I loaded the ERacer250 UAV settings from the other post, (I never did find his video), but every time I load his settings it messes up my transmitter and I cannot arm the quad. Any Ideas. I am using a FS_TH9x transmitter.
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His video was posted wrong, try https://www.youtube.com/watch?v=uBws1mQiwn8
You'd have to write down your current hardware and input settings before loading his settings. And then put them back after you'd loaded his uav config.
I was originally just thinking you could look at his settings, the stabilization tab mostly, to see what worked well for him.
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Thanks for posting the video. I will see if I can get his settings.
I keep looking at all the PID settings people are talking about, but I,m not sure that is my problem. I don't see it ocillateing like they are saying. When trying to hover it will slowly Yaw to the right and drift to the right. Is this still PID's or something else.
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Remember you need to keep your frame still while wait Gyro init after you connect battery.
Fast led blinking = do not move quad.
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Yes, I keep it still while it is booting.
I am a newbie in messing with settings, so I don't know if I am making the right changes. I don't seem to see any difference. As I said before, I don't see the ocillation like people are talking about, but I have a lot of drifting to the right and it continues to yaw right.
I,m looking for someone to point me in the right direction. PID's or something else?
If I set up Easytune, what is the Accessory switch for? Do you have a standard mode and flip the switch to use the Easytune settings?
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Try loading the config file attached.
It update only PID for all banks and do not overwrite others settings.
You will be able to do some Rolls or flips setting Rattitude, i have increased the rates to 400deg/s but added some expo.
https://librepilot.atlassian.net/wiki/display/LPDOC/Rattitude+Setup
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Thanks, I will look at loading the file, but It might not be until tomorrow.
As far as flips and rolls, I'm new at flying and you already want me to do flips on purpose. Ha Ha.
Right now I am just trying to get it to fly level and slow, then I can fly like you guys and Superman.
Thanks
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Thanks, I loaded that file and it definitely helped. I can see some slight oscillation and it wants to drift backwards. It is also hard to maintain a level altitude when hovering. It seems like the slightest throttle correction makes it bounce up and down.
Is this just the characteristic of these copters?
What settings do I need to change to balance it out now?
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I found another post on Easy Tune -https://forum.librepilot.org/index.php?topic=1106.msg8079#msg8079- and think i'm starting to understand it, but where do I get the Min and Max settings for it?
I thought that I would get them from the INPUT screen for the controller, but the ones for Easy Tune are in decimals. Where do they come from?
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It is also hard to maintain a level altitude when hovering. It seems like the slightest throttle correction makes it bounce up and down.
In the GCS see Vehicle - Throttle Curve to soften/flatten the 'useful' range of stick motion.
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I would like to bind Easy Tune to one of my rotary knobs on my controller. How can I get the Min Max numbers?
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Dronin has a really nice autotune that I used on my ER250. Worked like a champ.
Sent from my iPad using Tapatalk
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Who or what is Dronin?
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I found the Dronin Autotunner. I will take a look at it. Thanks
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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
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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.
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I found the Dronin app. It looks just like EasyTune so is there any difference?
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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.
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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 https://www.youtube.com/watch?v=LtocGBngSrA
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.