My Quad copter with Naze / AIR Hero•32 is twitching
I tried to balance all my motors and props but i get a random little twitch in the air frame and loose RC for sec now and then. Is there a HACK to fix this?
Vibration is best REMOVED by analog balancing - 100% always - no matter what - use copper tape to balance motors and blade tape to balance props - do static and dynamic balancing
However it's worth understanding that if you are desperate and prepared to sacrifice lazy balancing for some of your control responsiveness - then you use ACCLPF and or GYROLPF software filters
the naze32 defaults (same as AIR HERO•32 defaults in Baseflight) are
gyrolpf = 42 // this is in Hz - so 42 = filter out anything higher than 42hz acclpf_factor = 4 // this is just a numerical factor of oversamples of the ACC - so 8 will have twice the effect of 4
if you are getting a twitch in ACC modes ANGLE and HORIZ - then switch to ACRO mode (uses gyros only) and see if the problem is still there. If yes then land and balance your motors and props (OK you don't want to do this) - so use the Baseflight CLI to set more aggressive LPF for the gyro - realise this will dull down the control rate - valium for the AIR - so to dull it down you could choose to try 20hz filtering
set gyro_lpf = 20
A larger Quad will have a resonance frequency of around 45hz so 42hz works well
but for - a 250mm sized quad a resonance of around 150hz - so gyro filtering can be raised to 100hz set gyro_lpf = 100
100hz is safely below the airframe resonance frequency, and will give you twice the response rate of 42hz default - but you would have to balance everything to a tee. the problem comes in when you get harmonics - so harmonics of 33hz/66hz can be present on a 132hz frame - this is especially true in poorly designed airframes, and dont forget different weights will give different resonance frequencies - so your friends Quad is not relevant unless he has all the same props, motors, ESCs and weight.
as a general rule do not increase the ACC factoring above 4 - unless you are really into experimental flying