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Users => Vehicles - MultiRotors => Topic started by: flavien317 on January 29, 2016, 07:22:09 pm

Title: Respond time quadcopter
Post by: flavien317 on January 29, 2016, 07:22:09 pm
Hi,
I have a 270mm carbon fiber quadcopter with a CC3D flight controller. The thing is when I go to right (for example, left, front and back are same) and immediately I go to the left, the quadcopter take about 1-2 second to go to the left. How can I fix it ? I need a quick respond time.

PS: I'm in mode 1
Title: Re: Respond time quadcopter
Post by: f5soh on January 29, 2016, 07:27:22 pm
This latency looks strange :)

For left/right are you talking about Yaw axis ?

Please post your config file: File > export UAV settings
Title: Re: Respond time quadcopter
Post by: flavien317 on January 29, 2016, 07:34:12 pm
Thanks for your reply, I'm not talking about the yaw, but the right stock on mode 2 transmitter (left / right and forward /backward)
Here is my parameters.

Thanks for helping me
Title: Re: Respond time quadcopter
Post by: f5soh on January 29, 2016, 07:53:32 pm
- There is something strange with one motor neutral, look Output tab.
- Start using same bank for all flight modes.
- Keep default values (Attitude response is reduced in bank1)
- Try to tune PID using EasyTune.
https://librepilot.atlassian.net/wiki/display/LPDOC/TxPID
Title: Re: Respond time quadcopter
Post by: flavien317 on January 29, 2016, 08:33:13 pm
- There is something strange with one motor neutral, look Output tab.
- Start using same bank for all flight modes.
- Keep default values (Attitude response is reduced in bank1)
- Try to tune PID using EasyTune.
https://librepilot.atlassian.net/wiki/display/LPDOC/TxPID

-I know for the motor, but if i put about same value of other, it not work.
-
-I keep all default for bank 1 i will try
-What is the PID ?

You think something is wrong with my quad ?
Title: Re: Respond time quadcopter
Post by: f5soh on January 29, 2016, 08:42:28 pm
Redo the Esc calibration... this neutral looks really strange.

https://fr.wikipedia.org/wiki/R%C3%A9gulateur_PID

PID defines the stabilization response but it will not take 1 or 2 seconds to move using default settings.

How feel your quad ? Under-powered ?
Where is the Throttle stick when hover ?
Title: Re: Respond time quadcopter
Post by: flavien317 on January 29, 2016, 08:50:01 pm
Redo the Esc calibration... this neutral looks really strange.

https://fr.wikipedia.org/wiki/R%C3%A9gulateur_PID

PID defines the stabilization response but it will not take 1 or 2 seconds to move using default settings.

How feel your quad ? Under-powered ?
Where is the Throttle stick when hover ?

I try to recalibrate the esc, i will see tomorow if it change. But for you it's a esc problem ?
Title: Re: Respond time quadcopter
Post by: f5soh on January 29, 2016, 08:59:22 pm
Not sure... but all esc are calibrated at same time, you should not see this difference from one motor to another.
Title: Re: Respond time quadcopter
Post by: flavien317 on February 05, 2016, 11:42:51 pm
Not sure... but all esc are calibrated at same time, you should not see this difference from one motor to another.
HI, i have try many things, but on mode 2 the response time was better. Can you send me your setup ? Your response time is good ?
Title: Re: Respond time quadcopter
Post by: f5soh on February 06, 2016, 12:07:17 am
Whats the mode2 ?

I don't have any issues with something like 1s latency... :)
Title: Re: Respond time quadcopter
Post by: NicholasDavid on February 06, 2016, 02:58:24 am
ummmm, is this for real.... 
Title: Re: Respond time quadcopter
Post by: flavien317 on February 06, 2016, 10:16:13 am
Whats the mode2 ?

I don't have any issues with something like 1s latency... :)

Bank 2 for intermediate mode
Title: Re: Respond time quadcopter
Post by: flavien317 on February 06, 2016, 10:16:40 am
ummmm, is this for real....

What it's for real ?
Title: Re: Respond time quadcopter
Post by: NicholasDavid on February 06, 2016, 10:40:59 am
Never mind. So do you want it to respond quicker/more twitchy. Is that what your after. Are you in auto level. Are you saying you push the stick forward and it tilts forward and it takes a second to start really picking up speed? What exactly are you asking.
Title: Re: Respond time quadcopter
Post by: flavien317 on February 06, 2016, 12:31:18 pm
Never mind. So do you want it to respond quicker/more twitchy. Is that what your after. Are you in auto level. Are you saying you push the stick forward and it tilts forward and it takes a second to start really picking up speed? What exactly are you asking.

How to know in which level I am ? Yes, for example if I go to the left and immediately I want go to right (not the yaw, haven't try yet) it takes a little time to go to the right. In the first mode is very low, and in the second mode (intermediate) it takes less time, but it's not almost immediately.
Title: Re: Respond time quadcopter
Post by: f5soh on February 06, 2016, 12:48:50 pm
Like i already say in previous post: https://forum.librepilot.org/index.php?topic=721.msg5217#msg5217

In bank1 you reduced attitude response.
Try tuning your frame using EasyTune for Roll/Pitch,  starting from defaults.
Title: Re: Respond time quadcopter
Post by: Mateusz on February 06, 2016, 12:56:33 pm
Never mind. So do you want it to respond quicker/more twitchy. Is that what your after. Are you in auto level. Are you saying you push the stick forward and it tilts forward and it takes a second to start really picking up speed? What exactly are you asking.

How to know in which level I am ? Yes, for example if I go to the left and immediately I want go to right (not the yaw, haven't try yet) it takes a little time to go to the right. In the first mode is very low, and in the second mode (intermediate) it takes less time, but it's not almost immediately.

This video explains nicely theory behind PIDs and how to tune them manually https://www.youtube.com/watch?v=LtocGBngSrA
If your aircraft behaves like elephant and reacts too slow, you PIDs (D term) are likely too high. If you change PIDs it gets more responsive but please watch the whole movie, it explains all behaviours.

LP has EasyTune which makes things much easier https://librepilot.atlassian.net/wiki/display/LPDOC/TxPID

In the two following attached pictures, you can see (I marked with red) the flight mode you choose on your transmiter, and associated with it stabilization and bank.

I suggest you start with setting Flight mode 1 to Stabilized 1 and using [Atitude (pitch), Attitude(roll) and Axis lock for yaw]. Thrust can be set to manual or CruiseControl.
Then make sure you use Bank 1 on first flight mode, and that your PIDs in Bank1 are tuned the way you want your aircraft to behave. Also make sure that when you flip switch to flight-mode 1, that it is selected in GCS.

To do that, the easiest is power battery, plug USB (best without props) and be careful not to arm your quad while doing this. If your transmiter is configured for more than one flight-mode you should be able to switch flight modes with the switch. It does not matter if you have just one flight mode. If your goal is just to set different pids for the bank used in that Flight-mode just make sure it uses that bank.

There is no magic, that works out of the box for all aircrafts. In vehicle wizard it is possible to pick frame that is as close to your configuration as possible, then it might fly better. But if you don't find one and generic stock PIDs are not good for your frame/build, then you need to do the tunning yourself.
That's the case with every flight-controller. Sometimes you get lucky and stock PIDs  work, but many times you need to tune.
Title: Re: Respond time quadcopter
Post by: flavien317 on February 06, 2016, 01:37:32 pm
Like i already say in previous post: https://forum.librepilot.org/index.php?topic=721.msg5217#msg5217

In bank1 you reduced attitude response.
Try tuning your frame using EasyTune for Roll/Pitch,  starting from defaults.
Thanks for your reply.
the attitude is not changing very much, i think its the D of PID.
Title: Re: Respond time quadcopter
Post by: flavien317 on February 06, 2016, 01:39:28 pm
Never mind. So do you want it to respond quicker/more twitchy. Is that what your after. Are you in auto level. Are you saying you push the stick forward and it tilts forward and it takes a second to start really picking up speed? What exactly are you asking.

How to know in which level I am ? Yes, for example if I go to the left and immediately I want go to right (not the yaw, haven't try yet) it takes a little time to go to the right. In the first mode is very low, and in the second mode (intermediate) it takes less time, but it's not almost immediately.

This video explains nicely theory behind PIDs and how to tune them manually https://www.youtube.com/watch?v=LtocGBngSrA
If your aircraft behaves like elephant and reacts too slow, you PIDs (D term) are likely too high. If you change PIDs it gets more responsive but please watch the whole movie, it explains all behaviours.

LP has EasyTune which makes things much easier https://librepilot.atlassian.net/wiki/display/LPDOC/TxPID

In the two following attached pictures, you can see (I marked with red) the flight mode you choose on your transmiter, and associated with it stabilization and bank.
  • Each bank defines PIDs
  • Each stabilization mode can be used for flight mode

I suggest you start with setting Flight mode 1 to Stabilized 1 and using [Atitude (pitch), Attitude(roll) and Axis lock for yaw]. Thrust can be set to manual or CruiseControl.
Then make sure you use Bank 1 on first flight mode, and that your PIDs in Bank1 are tuned the way you want your aircraft to behave. Also make sure that when you flip switch to flight-mode 1, that it is selected in GCS.

To do that, the easiest is power battery, plug USB (best without props) and be careful not to arm your quad while doing this. If your transmiter is configured for more than one flight-mode you should be able to switch flight modes with the switch. It does not matter if you have just one flight mode. If your goal is just to set different pids for the bank used in that Flight-mode just make sure it uses that bank.

There is no magic, that works out of the box for all aircrafts. In vehicle wizard it is possible to pick frame that is as close to your configuration as possible, then it might fly better. But if you don't find one and generic stock PIDs are not good for your frame/build, then you need to do the tunning yourself.
That's the case with every flight-controller. Sometimes you get lucky and stock PIDs  work, but many times you need to tune.

Thank you for this post, I understand the PID. I need to have two more buttons on my fs-i6 to configure PID ? I'm French so I haven't understood all.

In attachment my current setup
Title: Re: Respond time quadcopter
Post by: Mateusz on February 06, 2016, 02:00:47 pm

Thank you for this post, I understand the PID. I need to have two more buttons on my fs-i6 to configure PID ? I'm French so I haven't understood all.
In attachment my current setup

I don't know FlySky radio. But you have 6 channels. Pitch, Roll, Yaw, Throttle (4 channels) and 1 channel for flight mode. So 5 channels are used.
You have 1 spare channel. If you can use 6th channel with the knobs then you can use it to tune pids.

Alternative is to use laptop and bluetooth (or oplink) https://librepilot.atlassian.net/wiki/display/LPDOC/Setup+a+bluetooth+for+telemetry
and someone can help you to tune PIDs on laptop while you fly.



Title: Re: Respond time quadcopter
Post by: flavien317 on February 06, 2016, 02:40:36 pm

Thank you for this post, I understand the PID. I need to have two more buttons on my fs-i6 to configure PID ? I'm French so I haven't understood all.
In attachment my current setup

I don't know FlySky radio. But you have 6 channels. Pitch, Roll, Yaw, Throttle (4 channels) and 1 channel for flight mode. So 5 channels are used.
You have 1 spare channel. If you can use 6th channel with the knobs then you can use it to tune pids.

Alternative is to use laptop and bluetooth (or oplink) https://librepilot.atlassian.net/wiki/display/LPDOC/Setup+a+bluetooth+for+telemetry
and someone can help you to tune PIDs on laptop while you fly.

Thanks for your reply, I will just edit PID with the soft. But today is too windy. I will let you know if it's work after all my new setup :D
Title: Re: Respond time quadcopter
Post by: Mateusz on February 06, 2016, 02:45:23 pm
Thanks for your reply, I will just edit PID with the soft. But today is too windy. I will let you know if it's work after all my new setup :D

Yes, that's easiest. Connect laptop, lower D term in right bank, disconnect laptop. Try flying a bit. Repeat until happy :)
Good luck ;)
Title: Re: Respond time quadcopter
Post by: NicholasDavid on February 06, 2016, 08:40:10 pm
In auto level( if you let go of the sticks it leveles itself and hovers) on the basic tab the 3 sliders attitude, rate, rate yaw. Increase the attitude slider. And the P gain in the outer loop.  In rate mode(manual or non self leveling) it will rotate faster with the rate slider, and adjusting the P gain(on inner loop) will make it move quicker more robotic.  See if any of this makes a difference