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Old Jul 11, 2013, 07:14 AM
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The Twitching may also be related to Deadband although I never had to use it.

Code:
/* introduce a deadband around the stick center
Must be greater than zero, comment if you dont 
want a deadband on roll, pitch and yaw */

//#define DEADBAND 6
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Old Jul 11, 2013, 08:11 AM
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No I disabled the LPF and then just uncommented the first 2 lines in the moving average section. Just left the default values 15 and 10 From memory.

Did not muck around with dead band... Do you think it could be the control doing it. I'm more inclined to believe its just cheap noisy gyros ?
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Old Jul 11, 2013, 11:57 AM
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Well the deadband is aimed more to radios that can't center preciselly.
I'll throw the 9X in the list as it's giving me some hard time with that. The YAW pot in mine is really getting bad. Can be notcied as drift in the multicopter behavior when we leave the sticks.

For this twitching it is commonly caused by noise in the sensors or PID settings.
For example if it happens in fast forward flight it' spossible to use the ThrAttenPid setting ot reduce the effect of the PID's depedning on the throttle position.
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Old Jul 11, 2013, 12:05 PM
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I guess it all comes down to how Twitching is defined.
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Old Jul 11, 2013, 04:41 PM
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Originally Posted by IceWind View Post
Also interested in that.
jumped straight into the usual LPF of 42Hz and it got much better, but I could still noticed some very light twitching.
But increasing more it would leave the feel very mushy... and loose a bit to the crisp and fast response I'd like to have.
With 42Hz, it'll never be "crisp". Tried this out of curiosity, wow, no good. At 98 or whatever now, but I swear it was better 256. My conclusion: There's a reason the coders left it high to start with.
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Old Jul 11, 2013, 04:46 PM
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Originally Posted by Electro 2 View Post
With 42Hz, it'll never be "crisp". Tried this out of curiosity, wow, no good. At 98 or whatever now, but I swear it was better 256. My conclusion: There's a reason the coders left it high to start with.
My present understanding is, if it is possible to lower the vibration to the sensors, the high LDF is works best. This has a very possible side effect as well, better aerial video with less Jello.
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Old Jul 11, 2013, 04:50 PM
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Quote:
Originally Posted by jbalat View Post
No I disabled the LPF and then just uncommented the first 2 lines in the moving average section. Just left the default values 15 and 10 From memory.

Did not muck around with dead band... Do you think it could be the control doing it. I'm more inclined to believe its just cheap noisy gyros ?
Good to know. Thanks for the info.
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Old Jul 11, 2013, 04:58 PM
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MollieII HolyCrap (2 min 6 sec)


Made two really good passes here, Looks as if we have a little speed daemon.
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Old Jul 11, 2013, 06:31 PM
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Ireland, County Dublin, Dublin
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Quote:
Originally Posted by Electro 2 View Post
With 42Hz, it'll never be "crisp". Tried this out of curiosity, wow, no good. At 98 or whatever now, but I swear it was better 256. My conclusion: There's a reason the coders left it high to start with.
Yeah. I know that the default will give it a more "crisp" response, but it's quite common to use that with some sensors like the 6050. If I'm not mistaken the MwcFlip code has 42Hz by default.

Actually the LPF is only exclusive for two gyros, 6050 and ITG3200&ITG3205 and like the comment in he code says only if we can't remove the twitching caused by vibrations. And that was my problem.
The highest I could set without much twitching was 98Hz.
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Old Jul 11, 2013, 09:24 PM
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Did I find the right thread --> I bought a quad that is coming with a "MWC pro 3 & GPS" already tested and setup.

I have experience with the GY-344, several FY-90Q's, and a Naza.

What's the best source for helping me get a grasp with this flight controller?

I'm very excited to fly with this new controller - I have been programming with Arduino for a while so this will be fun.

I hope.

Thank you

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Old Jul 12, 2013, 03:17 PM
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Quote:
Originally Posted by IceWind View Post
Yeah. I know that the default will give it a more "crisp" response...........................

Actually the LPF is only exclusive for two gyros, 6050 and ITG3200&ITG3205 and like the comment in he code says only if we can't remove the twitching caused by vibrations.........................


The highest I could set without much twitching was 98Hz.
I'd say remove the vibrations, not mute the FC, easy fix. On my present aircraft, there are no vibrations of any sort visible in the accelerometers GUI "graph-o-meter" gizmo. Nothing special, balanced motors and props before install, that's it. I never have observed anything I would describe as "twitching". Note that there will always be some periodic "shivers" in high indcedent wind conditions if the gains are set tight, i.e. high. This is not vibration induced, but the FC's response to turbulance cause by the air flowing across it. Shows up in a forced position hover in high, gusty, crosswinds. In still, clean, air, it vanishes. You can make this go away by lowering gains, but then the aircraft is "loose" and wobbly in normal flight conditions.
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Old Jul 13, 2013, 07:06 AM
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I think that the kind of twitching we are talking about here is not related to vibrations or wind. It is a random glitch coming via noise produced by the sensors.
As a minimum everyone knows they must do a really good job at balancing their blades and motors and turning down the gains to eliminate any feedback wobbles.

If it is just electrical noise then it may be coming from a noisy esc or motor and maybe its not the sensors at all, it could be solved by a capacitor or ferite coil ?
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Last edited by jbalat; Jul 13, 2013 at 07:15 AM.
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Old Jul 15, 2013, 02:24 PM
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gps hold

hello
I can not seem to find the problem hold the GPS works well north and south not work??

je n'arrive pas a trouver le problème le GPS hold marche très bien direction nord et marche pas au sud ????
carte pro 2,0
gps ublox 6
multiwii 2,2

Multiwii problème (1 min 2 sec)
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Old Jul 15, 2013, 05:38 PM
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Quote:
Originally Posted by f0cyq View Post
hello
I can not seem to find the problem hold the GPS works well north and south not work??

je n'arrive pas a trouver le problème le GPS hold marche très bien direction nord et marche pas au sud ????
carte pro 2,0
gps ublox 6
multiwii 2,2

http://youtu.be/2ZQP3h-zypY
Do you have the MAG enabled or you're just using the GPS and LEVEL?
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Old Jul 15, 2013, 06:34 PM
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Originally Posted by IceWind View Post
Do you have the MAG enabled or you're just using the GPS and LEVEL?
There is also a MAG correction factor you need to put into config.h depending on what part of the world you are in
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