LibrePilot Forum
Users => Vehicles - MultiRotors => Topic started by: claytonbakerjr on March 07, 2016, 11:26:27 pm
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I remember back in the day a sticky or something with this title. Maybe else where?
Does it still exist and if so could you please direct me at it.
Basically I am flipping and Rolling but I feel the sticks are just too sensitive to touch.
I hardly move them and the quad is kind of herky jerky yet I see guys fly in Rate and
their transition in their stick movement is smooth.
I read something about dialing in expo? to help this but that is another pain point for me
since I honestly have no clue :(
I have attached 2 pics with some of my settings which show my Rate and Rate Yaw is set at 575. Also where it shows Acro+ I increased roll and pitch factor to 50. Truthfully what does this do?
Any way any little bit of knowledge would be great.
Currently I like how she is flipping and rolling I just want to get rid of this herky jerky sensitivity.
When I get better I want to increase the speed just a little :)
Thanks very much
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Currently I like how she is flipping and rolling I just want to get rid of this herky jerky sensitivity.
You want more velocity and you run default PIDs ? Well, why not...
You should tune your frame first, and finally discover new capabilities.
Take a look here:
https://librepilot.atlassian.net/wiki/display/LPDOC/Advanced+tuning
Acro+ factors only applies while using Acro+ stabilization, no need high rates because at full stick motor go into manual mode (direct command from stick to motor)
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https://forum.librepilot.org/index.php?topic=893.msg6490#msg6490 has links to the archive.org copy of Flips n Rolls for Newbies.
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Also you are looking for expo. The second picture on the basic tab. That little graph thingy. Add say(I like a lot of expo) 50-80% and see if that softens it up a tad. But yeah a good tune will do wonders. You probably have a twitchy copter cause your P and D gain are out of whack. But also pitch and roll expo. I run about 72% expo on my pitch and roll for all(2) of my acro quads, With high rates around 550-600 degrees per second.
The acro plus factor is in degrees per second also. So you can run nice easy to control low rates 180-300 I would say and run a 50-60 acro+ factor so when you go full stick it flips at 500-600 degrees a second but general flying, its at the lower 180-300 rates.
I personally like rate mode. with high rates and lots of pitch and roll expo. But that's just what I'm used to so I stick with it. Full control.
My third bird is pretty much for fast cruising. And I run low rates on it, still with about 70% expo on pitch and roll. All my fixed wings are running expo as well. I find it just makes things easier to fly
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I have been told I need to [possibly do some adjustments with my dirivites but from what I can see
the only oscillations I get is when I come down from like a full punch out but other than that
she (to me and my skill level) seems very solid. But I will check out the link and thank you
Currently I like how she is flipping and rolling I just want to get rid of this herky jerky sensitivity.
You want more velocity and you run default PIDs ? Well, why not...
You should tune your frame first, and finally discover new capabilities.
Take a look here:
https://librepilot.atlassian.net/wiki/display/LPDOC/Advanced+tuning
Acro+ factors only applies while using Acro+ stabilization, no need high rates because at full stick motor go into manual mode (direct command from stick to motor)
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So from what I see most of you actually fly Acro+?
After reading more it seems a logical choice especially
with what I am looking to do, would that be a good assumption?
It would be great to see a Hybrid, Attitude while flat lining and Crazy
for the flips and silly stuff we do lol.
I know AttiRoll :)
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The hybrid mode is rattitude mode. Attitude and rate hybrid. But I think most people eventually graduate to rate mode. Or acro+ with high rates and an even higher acro+ factor. Rate mode is the eventual goal, for almost all acro flyers.
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I see, thanks.
One other thing that kind of confuses me is the Flight mode position for the switches.
I see in a lot of videos and pictures that even though people have defined Flight Mode pos 1 pos 2 ect
the Settings Bank remains the same. Should the banks match what you have in the Stabilization tabs?
Would that be for a person who is only flying rate or Acro+ and never flying in attitude? Therefore only using
bank 1 for example?
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My early copter and how I learned was. Use a 2 or 3 position switch. And have them set for different banks. So on a 3 position switch I have. Bank one basically defaults in attitude mode/self level with like 45-70 degree max bank angle. And that's my safe bank that I can switch back to at anytime and be in auto level and it's easy to hover and all that
Then bank two maybe set up as rattitude or acro+ if your so inclined. And start flipping while flying and get used to more banking angle and higher rates. If that's all the positions on your switch then maybe do bank two as a rate mode so you can start learning. And you can always switch back to the first bank with the switch if you get into trouble.
If you have three position switch then I would setup the first two banks as attitude mode so it's pretty easy to fly. One with all default settings. And bank two as the same with a higher max bank angle. So you can kind of feel what banked turns are like. And get used to rolling over farther in a turn. Then set up a third bank all rate mode. Full manual control. No auto level, no accelerometer. That's where these machines really shine. Every acro pilot you see on YouTube doing these crazy acrobatic moves flys in rate mode.
Yeah if you watch thoes old videos thoes people had a lot of mistakes and didn't seem to know much about what they were doing. Most of thoes settings videos were all default numbers anyway
It's better to search YouTube and the forums for how to tune PIDs your self and watch many many hours of video and read a lot and educate yourself on the whole tuning process. Then just start trying stuff. And don't just look for openpilot/LIBREPILOT videos either. There aren't many of thoes. All PID tuning is basically the same. It's just the numbers that will be different. The process and goal are the same.
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Thanks Nick I appreciate it.
Here is a video of me flying today doing some flips and rolls.
You will notice the herky jerky thing I am referring to is more so
me on the sticks, but as earlier mentioned it could also be a result
of poor pids.
Enjoy LOL...at the end I decided to stop the video because I got a bit cocky
and due to this "sensitivity" I either over or under corrected as a result :)
https://www.youtube.com/watch?v=vp_b5taP13I
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hummm where did my link go to?
I can see the link in edit mode but not when published.
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Expo is what you need if it's too "touchy". Can't see the video yet
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https://www.youtube.com/watch?v=vp_b5taP13I&feature=youtu.be
if that didnt work try this
(https://www.youtube.com/watch?v=vp_b5taP13I&feature=youtu.be)
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I see a little bounce after some flips and rolls. And it looks loose. Like its sliding all over the place. Hard to keep tracking in one direction. Some of that is pilot. Some of that may be expo, but 85% of that all over the place feel and sliding about is the tuning. It's looks mostly smooth and doesn't bounce as bad after a flip as it does a roll but it would fly a whole lot better with a solid tune and just fly
By the way positive expo. If you do negative it will be more sensitive.
Set your rates lower and move the acro plus factor up. Generally it should be higher than your regular rate response and max rate limit
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expo is backwards on futaba vs. spektrum.
The video looks like the rolls stop on a dime and that is good. I guess I would have to fly it or watch you fly it to tell.
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Ok as Cliff mentioned it does seem to stop on a dime where ever I release the sticks.
So as per PID tuning, when I hoover with it and slap sticks left, right forward and backwards
she pretty much comes back to attention with very little wobble which to me (correct me if I am wrong)
is essentially what I want? Correct?
when I punch her out she rolls up smooth and seems very stable. The only time I get oscillation is if I drop her very rapidly
but as soon as I get to a level I want to stop her at she reacts without delay and in no way seems sloppy. Thats pretty much true of all of my CC3D equipped quads.
Now then this is with default PIDs in Attitude.
So lets say she was a bit sloppy, do I adjust PIDs in Attitude or do I adjust in all modes I fly in?
Now another pain point is within GCS I see under the Advanced tab the only reference to PIDs. a set for Roll, Pitch and Yaw. I assume this is the correct area to adjust PID's in GCS?
What I read is to adjust P first then I and then D. I have attached a pic of my default PIDs for reference.
This is the area that is painful in light of the numbers. I suppose I could just start raising numbers until she goes crazy but I have also read people stating starting points. For example one video the guy says set all of my P's at 200 and everything else at 0...really?
Anyways...
Tonight I have spent some time looking over videos and reading and what I am planning on doing is setting up all 3 positions as follows.
1: Attitude
2: Rattitude
3: Acro+
I plan on using the same numbers I had with the rate but as Cliff mentioned Expo is different with a Spectrum which is what I have, DX8.
So does that mean instead of increasing the number I should decrease them to smooth out my stick control? I would also assume that this is mostly for Pitch and Roll and not so much for Yaw?
I would be glad to video tape the quad in question but I would ask that you coach me on what I need to do to help you in letting me know if for starters the PIDs need work before I waste a lot of time of tweaking the Modes. With the upcoming weather in my area and the winds we have been having the short term would be something inside. I can compile some video of this past weekends outdoor flights during some playing around with the guys.
Any who thanks so very much for sticking with me on this. I really want to learn and it seems that the only help I am getting is from this site. Seems getting help from the boys is harder than I thought. Seems its some sort of protected information LOL.
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Hi,
Much better set Expo on board, see here:
https://librepilot.atlassian.net/wiki/display/LPDOC/Expo+setup
You should have more precision around center.
You can reduce the Attitude "P" but do not set to 0 or you can loose control in Attitude stab mode.
the Attitude "P" is the last stuff to adjust, tune the Rate PID first using OPTune or EasyTune and a knob.
https://librepilot.atlassian.net/wiki/display/LPDOC/Attitude+Setup
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Ok
So increasing Expo (Input of stick) reduces (output of stick) essentially smoothing out stick control on the copter.
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Aaah , " flips n rolls for newbs" on OP forum , I remember it well - think I even copied some of it into a notebook.
I too use a dx8 , and not often having laptop access , use the expo function on the TX to set a bit of expo when easing myself into a new build.
(I prefer flying with linear response as a norm)
It may be a good place to look , as it does show you exactly what your stick input translates into.
As it were.
Please note , am only a beginner myself and definitely not suggesting I have tech knowledge.
Cheers
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I hope the Expo page on wiki explain the expo feature...
(https://librepilot.atlassian.net/wiki/download/attachments/19890199/expo_multiple.png)
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Once this rain moves through I am going to pack the laptop and quad up and go mess around with the expo.
I will also film some video FPV and external to show flight characteristics to post.
Thanks to all for the info
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Ok so I had time to play around with the Expo and the other flight modes.
In Rattitude I noticed that stick movement was very lax or very slow to respond
which tells me that I should maybe lessen the amount of Expo I put in? Would you agree?
In Acro+ I seen that I was flipping very fast which leads me to think that
I should lower the roll factor? Correct?
Now as per Roll Factor does it apply in Rattitude or only Acro+?
I did some recording but I am at work right now.
After messing around with fast inputs to see how quad reacts
I see that maybe I need to play with the PIDs a bit to make it more snappy.
It reacts good but after looking directly at the quad I feel it needs
to react faster. Recovery from snap that is. It is a smooth to pop back
transition and not so much a snap to attention transition?
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Well I've spent some more time researching and this video kind of sunk in a bit more than the others I have found.
So please correct me if I am still lost.
In Attitude mode it seems pointless to actually tune PIDs since this is a auto level mode?
In Rattitude I would summarize the same since from my understanding until you reach a
specific stick percentage your kind of still in Attitude, so again tuning is pointless?
I gather that tuning should be done in a Rate mode only to actually see the effects of your tuning
without the Auto Level interfering?
https://[size=78%]www.youtube.com/watch?v=JNvA7tutirc[/size]
[/size]
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Correct all the way around
Video link does not work
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First of all, let me say that the best advice is to use default setup until you actually understand what it is you are changing and why you need to change it. Don't just turn something on because it sounds interesting or because someone tells you to. Research it and make an informed decision.
PIDs are like a car's suspension. In a car, the suspension is factory tuned to allow the quickest response the vehicle is capable of. Not that you use hard cornering every day, but there is just zero reason to have a suspension that is tuned less than perfectly. The problem with our quads is that we are the tuners and there is no factory perfect tuning. We have to do it ourselves. Default values usually work pretty well. Cloud configs sometimes are better and sometimes worse.
Besides the tuning, there is a "maximum roll/pitch rate" and a "(rate mode) rate" and a "maximum bank angle in attitude mode". I can't tell whether your slow roll rate is because of these or because of a bad PID tuning.....
For a newbie wanting to do flips I recommend Rattitude stabilization mode on roll and pitch, AxisLock on Yaw, CruseControl on thrust.
Also: In GCS -> Configuration -> Stabilization -> Advanced (for what ever bank you need to adjust) there is a max rate, a rate and a a max bank angle (I forget exactly what they are called :) ). The default rate is 220 which is just too slow for flips. I recommend that you set both max rate and rate to 360 for starters. That is one flip per second. Watch a clock with second readout and imagine flips once a second. It is quick enough to get it done, but slow enough to visually track even the first time you do it.
After setting these to 360, see if the response is more acceptable. If you want Attitude / Rattitude (close to level) to have a fast rate then I recall that max rate is what you want. If you want Rate mode to have a faster rate, adjust rate, but be aware that making rate higher than max rate then rate gets limited by max rate... Acro+ uses rate at close to center stick, so you can adjust center stick for Acro+ with that. It uses Insanity Factor though for large stick positions.
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Hey Cliff
I couldn't agree more with in light of tuning.
I kept looking at things and decided to not touch the PIDs.
I am really just a beginner in light of the experience here on this site
and once my skill level increases to where I truly understand what
is happening I am going to leave well enough alone for a bit.
The more I read the more it was pounded into my head that "you
have to adjust PIDs". I personally don't feel it is necessary in my case.
The bird flys well currently and I'm good with that.
As per flips and rolls, I ended up just staying in Acro+.
Once I did some tweaks to the numbers and speed as well as Expo
I began to feel more in control.
I did try Rattitude and in that I liked it I still felt kind of weird with
messing around with the flips and rolls.
I spent some time Saturday in the field and brought the laptop
and tweaked Acro+ to a point to where I am almost flying as well
in it as I was in Attitude.
I did see some situations during flight that lead me to believe I do
need to play with the PIDs and once I get more experience under
my belt I will mess with them.
Thanks for everything
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Correct all the way around
Video link does not work
Yea sorry I seem to have the worst time here getting links to work.
Sometimes they are there others just text and other times they just dont post :/
Copy and pasting it (address only) did work after the fact. Sorry