Aung Ko

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Throttle doesn’t increase gradually...
« on: October 22, 2018, 08:20:51 pm »
My quadcopter, Q450 doesn’t fly gradually when I increased throttle. It’s is like too responsive. Where can I Tune this? I tried calibrating ESC with GCS, still don’t work. Even worse, motor increased its self and hit the ceiling. I am not a very bad pilot. Already built 2 quad and flied well. Please help me, any answers? sources? Link? (modified by TOC to use youtube.com instead of youtu.be)
« Last Edit: October 23, 2018, 12:25:14 am by TheOtherCliff »

Re: Throttle doesn’t increase gradually...
« Reply #1 on: October 23, 2018, 12:35:26 am »
How much throttle stick was that?  What happens if you give 1/10th stick?  Same thing?

Is this CC3D or Revo?  How did you tune the PIDs?

I would guess either:
- Input Throttle min/neutral/max is not good.  It should usually be about 1000/1040/2000 (not 1000/1500).  Sbus numbers a little lower.
- D term of PID is too high and you are getting D term oscillations (invisible oscillations).
- Output mins/neutrals/max are not good (should usually be 1000/1080/1900) or ESCs are not well calibrated.

Aung Ko

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Re: Throttle doesn’t increase gradually...
« Reply #2 on: October 23, 2018, 09:03:54 am »
I am using CC3D atom. The pos of throttle sticks was just Min. I didn’t know much about PID, so they were all in default. Throttle Input is 997/1045/1990
Output config is 1000/1043/1900

I think it’s about PID because I found that In flight mode 3 which is rate and manual. The motors spin well...

Here is the video
https://m.youtube.com/watch?feature=youtu.be&v=mXDBW1f_oqE


I don’t know how to tune PID, so if you have any good document or video please give me or any answers?

Re: Throttle doesn’t increase gradually...
« Reply #3 on: October 23, 2018, 09:27:58 am »
Do all your flight modes use the same PID bank?  Input -> Flight Mode ... page

You could try setting all your D terms to zero for a test.  You could also cut all your P's and I's in half at the same time. just for a test (it will be very mushy, hard to fly, but throttle may work well).

If Rate and Manual works, what is the mode that does not work?

If you attach your settings UAV file, it would help.  File -> ExportUAV...

Aung Ko

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Re: Throttle doesn’t increase gradually...
« Reply #4 on: October 23, 2018, 10:11:17 am »
I really don't know where is I where is D and where is P. I don't know how to tune. Here is my UAV file. I just reset the vehicle setup again. But didn't solved the problem. In throttle neutral motor spin more than proper speed. I have no idea what to do next. Please help. Here is my file

f5soh

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Re: Throttle doesn’t increase gradually...
« Reply #5 on: October 23, 2018, 11:18:57 am »
You need to check the option "Zero the Integral when Throttle is low" in Stabilization tab > bottom of page.


Aung Ko

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Re: Throttle doesn’t increase gradually...
« Reply #6 on: October 23, 2018, 12:20:05 pm »
Already did and still not fixed

« Last Edit: October 24, 2018, 03:55:58 pm by TheOtherCliff »

f5soh

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Re: Throttle doesn’t increase gradually...
« Reply #7 on: October 23, 2018, 12:41:56 pm »
Try the settings file attached and try flying outdoors, indoors testing in never a good idea.
If you increase Throttle slowly the "Zero the Integral when Throttle is low" option has small effect, especially if I terms are high.

Aung Ko

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Re: Throttle doesn’t increase gradually...
« Reply #8 on: October 23, 2018, 04:45:00 pm »
I have not test outdoor flight ye because it’s already Night in my country. That’s what I get when I import the UAV file you gave. Still the same answer. When I increase throttle, motors spin fast and reach to like 30% it’s self. But in flight mode 3 motors responsed well. So, I think I have to tune ESC and throttle well. But I don’t know how to tune. Here is my demonstration video...

« Last Edit: October 23, 2018, 09:14:02 pm by TheOtherCliff »

Aung Ko

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Re: Throttle doesn’t increase gradually...
« Reply #9 on: October 23, 2018, 04:58:15 pm »
I saw that video, the situation seems same with mine. I need to go out and test bravely 😁 first
I will reply after I fly

« Last Edit: October 23, 2018, 09:14:31 pm by TheOtherCliff »

Re: Throttle doesn’t increase gradually...
« Reply #10 on: October 23, 2018, 09:32:04 pm »
Motors increasing slowly in Attitude mode is normal when on the ground or with props off.  When Attitude (bank angle) is a little wrong, it speeds up some motors to make the Attitude correct.  Because it is not in the air, it does not move, so it tries harder and harder.  If props are on and it is flying, then the first smallest motor change will cause the Attitude to change and it will not have to spin up faster and faster.

In Rate mode it does not care that it is not perfectly level so it does not spin the motors faster (a simplification of what actually happens).

I think maybe that you don't actually have a problem, but you are not used to controlling the quad throttle.  :)  The first thing you must learn is how tiny tiny changes (like just 1mm) in the throttle is the difference between slowly (which is what you want) climbing and slowly descending.  In order to keep it at waist high, you will always be adjusting the throttle up and down by the tiniest amount possible, just like when driving a car on a straight road, you use the smallest amount of steering to keep it centered in the lane.

As long as your quad is not super super powerful then reducing the throttle to say 1/4 should cause it to descend (with motors still turning); and as long as your quad is not weak, then increasing the throttle to 3/4 should make it climb.  The key here is to find the place where it is not climbing or descending and from there, only use maybe plus or minus 2mm of throttle stick movement.  If you use more, you over control.  As @f5soh said, do this outside until you "get the feel of it" and can control altitude.

Aung Ko

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Re: Throttle doesn’t increase gradually...
« Reply #11 on: October 23, 2018, 09:42:13 pm »
I am not pretty sure yet that it is an error or normal because as I said I have built 2 quadcopter and I flied well. I am sure I am not bad at handling throttle control. I first built a quad with QQ super and other with CC3D atom which is the one I am using now. With the previous CC3D one, I was able to fly well indoor. Without tuning anything only with default setting. Now I did the same, setup same motor  and ESC values, same frame but the present one doesn’t response same as the old one. So, I thought it is a problem. Because typically it should fly well indoor right? I will try outdoor flying and I will reply the result. Thank you for all your help. I attached my UAV setting file. Please I request you to view it if something is wrong. Thank you all for all your discussion and I will stay tune.

Re: Throttle doesn’t increase gradually...
« Reply #12 on: October 23, 2018, 09:57:28 pm »
It sounds like you have experience.  That leaves 3 things I can think of:

ESC calibration:  You said you did it, but here are instructions you can try:
https://librepilot.atlassian.net/wiki/spaces/LPDOC/pages/12058743/ESC+Calibration

FlySky transmitter has a problem that can be fixed.  Here is a way to see if you have the problem and how to fix it:
https://www.rcgroups.com/forums/showthread.php?2145070-New-Flysky-FS-i6/page117#post38300831

More powerful than you are used to will make altitude harder to control.  You can add some "expo" with a curve on throttle, but beware that it will not be centered on center stick, but on hover power location, where ever that is.

------------------------

You can plug in USB and flight battery and turn on transmitter and go to GCS Input page (or HITL page or System->Objects->ManualControlCommand) and watch to see if throttle responds correctly.

Is it possible that you have some throttle curve or throttle mode set in the transmitter?
« Last Edit: October 23, 2018, 10:03:23 pm by TheOtherCliff »

Aung Ko

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Re: Throttle doesn’t increase gradually...
« Reply #13 on: October 23, 2018, 10:21:03 pm »
I said I did ESC calibration was according to the exact same link that you have mentioned. My throttle curve from transmitter was normal, linear graph. HTLM aslo work correctly. Do you mean try to add expo to throttle curve mean change output throttle curve ( vehicle setting) or on thrust PID scaling (stabalizing advances setting) ?

Aung Ko

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Re: Throttle doesn’t increase gradually...
« Reply #14 on: October 23, 2018, 10:22:21 pm »
My throttle curve from tx

And tx display showed correctly