Hi @xfacta
I have been using 110kg class octo/ quad x configuration with hobbywing propulsion system.
I have set following PID
Rate roll P 0.225
Rate roll I 0.225
Rate roll D 0.015
Similarly for Pitch also.
And attitude Angle was both pitch and roll P is 5 and acceleration MaX is 30000.
I get hot motor after land but i don’t get any motor mechical noise while flying.i know this is because of higher PID but if i reduce the PID the drone not fly well .
The Rate D term is usually anything from 1/16th of P and I term right down to 1/50th.
Yours is 1/15th which might be too high - you could try D term of 0.0075 to bring down the motor temperature as a temporary measure - but we cant really say much more without seeing a log.
With a D term that high, your other Rate and Angle values might be wrong, and you are using that high D term to compensate for some other anomaly.
Make sure you have set
INS_LOG_BAT_MASK,1
INS_LOG_BAT_OPT,4
LOG_BITMASK,180222
hi @xfacta as per your suggestion i have made the flight test with Above setting for LOG .
as well as D term start with 0.0075 .but when reduced D term drone started behave very sluggish. when i increase D term it start improve the performance along with P term of the RATE controllers.
i have followed Initial tuning instruction for Hormonic Notch filter too.
the log google drive contains 3 log
in loiter mode if i fly more faster the height also keep decreasing as increases the distance. After leave the stick height automatically increases by the loss height in the fast flight.
i have tried EK3_ALT_M_NSE parameter to 4 .that also not helped.
Your voltage failsafe levels might be wrong, since the battery voltage really drops off at the end of that flight. An RTL is initiated but you cancel it by mode change, and you are really into the critical voltage area.
Apart from graphing the voltage to see the fall near the end, you can see in the motor outputs → there is a noticeable increase in motor outputs over time as they are commanded to higher output to deal with the falling voltage. This will be drawing more current, and making the voltage fall faster…
This is why all the correct voltage failsafe values and actions need to be put in place, because you cant see these effects “by eye”. When a pilot gets busy, watching a voltage and doing calculations in your head is impossible.
EVEN DURING TESTING
The battery pack will be damaged, or at least lose capacity, if this is repeated.
Definitely set BATT_FS_CRT_ACT,1
I think you will need some conservative voltage settings, or least a short timeout value.
BATT_LOW_TIMER,5
Try to get the current monitoring working too, that will be useful information.
What kind of battery pack is it?
The vibrations seem a bit excessive, particularly because X and Y axis vibes are very unequal. This indicates damping is not equal in all directions, or something is pulling or rubbing on the flight controller.
You should do more to reduce vibrations.
Please also provide photos of the flight controller, its mounting and its wiring.
The harmonic notch filter settings are wrong - a harmonic is targeted instead of the base frequency. Set these - and leave the logging values in place until every bit of tuning has been done.
INS_HNTCH_MODE,1
INS_HNTCH_REF,0.26
INS_HNTCH_FREQ,29
INS_HNTCH_BW,12
INS_HNTCH_FM_RAT,0.7
INS_HNTCH_HMNCS,3
INS_LOG_BAT_MASK,1
INS_LOG_BAT_OPT,4
Attitude control is very noisy, and D term is definitely too high.
Start with this and do a flight with Stabilise and AltHold, don’t rely so much on Loiter yet.
ATC_INPUT_TC,0.20
ATC_RAT_PIT_D,0.0055
ATC_RAT_PIT_I,0.11
ATC_RAT_PIT_P,0.11
ATC_RAT_RLL_D,0.0055
ATC_RAT_RLL_I,0.11
ATC_RAT_RLL_P,0.11
But dont rush into doing further flights until you’ve attempted fixes for the vibrations - vibrations are a physical issue that often cant just be tuned out.
its Solid state battery .i don’t find any current sensor to this drone capacity because it approximately continues current is 250A.
i have done very carefully with wiring and autopilot its mounted with rubber damper and ESC signal wires is well enough free s and its not pulling the FC anyway i believe.
harmonic setting i have changed your suggestion parameters but WHY INS_HNTCH_BW =12 when INS_HNTCH_FREQ is 29. it should be 14 right?
as i already told that if i start with low RATE P and D in manual flight it is not that much controllable compared to current PID. Lower rate PID its very Sluggish to control or fly.
Have you got a link to the battery online? Or describe it more detail, because there’s now “semi solid state” LiPos and Li-Ion battery packs and they have different voltage ranges.
Granted, yes it’s going to be hard to measure that.
In your photos of FC and wiring…
Secure ALL the loose wiring.
The servo wires that come from the carrier board do need flexibility, but the way you have them now the weight of all those wires is pulling on the carrier (and flight controller). All movements and vibrations of those wires will be transferred to the carrier and FC. You need to secure them to the base plate near the flight controller.
This would be a better flight controller antivibration mount since it angles the silicone dampers better.
I chose this from your flight data. It is a general guide that BW should be half of FREQ (as a starting point) but it is much better to keep BW as narrow you can and still be effective. A wider bandwidth than necessary just introduces more lag. After you’ve sorted out vibrations a quick test flight in AltHold will give us some updated data to recheck the HNOTCH settings.
Yes, understood. It could be that Rate P and I have to go higher yet. I think it will become much clearer once vibrations are improved and we see the full effect of the HNOTCH settings.
Leave them how you have them for now, and we will revisit this later.
