Tricopter upgrade

[wm175]

Currently running tricopter with cc3d board and Afro 30a esc.
Built it back when the frame first became available on the website.
Anyway just ordered kakute f4 v2 and some new 35 amp esc any suggestions to make board setup easier would be greatly appreciated

[wm175]

I’m wiring up the tricopter with a kakute v2 aio
The servo needs power… not sure if I should use the extra esc pad with an Ubec 4s to 5v or the 5 volt off the board… the 5v off the board is only rated for 1.5a…. but it’s the only thing I’m going to use for that. The vtx will be off the vbat

[jihlein]

If you can find one, a 6 volt bec run off the unused esc pad would be the best bet. The servos are faster at 6 volts which improves the yaw performance.

FWIW, this is the primary reason for not using AIO and stacking the “regular” KakuteF4V2 on the mini PDB, it has a six volt output.

[wm175]

So I crashed my tricopter and killed my servo. Ordered David’s servo and installed it. I’m using kakute f4 aio baby pdb and the 3D printed tail setup. I reinstalled the Dronin firmware and ran auto tune set the d term on yaw to 0 and tried running the in air tail tune. When I hooked it back up to the laptop but it is not saving the tail tune the motor thrust factor stays at 13.8. Any suggestions.
After I run the tail tune I disarm them take it out of tail tune them unplug the battery.

[jihlein]

Two questions.

Have you:
1)Made the necessary setup steps to use the fdbk servo, disable the virtual servo and select ADC2 for fdbk in the triflight setup objects? (Assumes FDBK wire is connected to Rsi pad on KakuteF4)

2)Run the on-ground portion of the tail tune? Did it complete correctly?

Reason for asking is your procedure for the in air tailtune appears correct, so looking to see if the setup steps completed correctly first. I should also note the you must stay of the sticks during the in air part because the algorithm is looking for trim, so if you on the sticks, your not in trim, and no data will be collected. It’s okay of the copter drifts around a bit.

[wm175]

My bad I should have said all the steps are complete. The on ground tail tune worked properly. It was a little windy and I had to be on the sticks a little more than the first time I did this procedure a couple months ago so maybe that’s it. I’ll try and run it again on a calm day and post results.
Thanks for the help.

[wm175]

Ok that was the problem. The tail tune saved this time I guess yesterday was just too windy requiring way too many stick inputs.
P=118
I=409
D=0
It does really well until high throttle input then the Yaw wobbles pretty hard.
Not sure which one to start adjusting.
The props are balanced.

[jihlein]

Don’t adjust the PIDs, they are tuned for the hovering state. Lets try this:

Since you’ve done an autotune, the SystemIdent object will have a non-zero value for HoverThrottle. Note this value, and then save it in the TriflightSettings.DynamicYawHoverPercent object. Now start reducing TriflightSettings.DynamicYawMaxThrottle and see if that starts to fix the yaw oscillations at high throttle.

What this does is linearly decease the yaw loop gain from the nominal hover values, starting from the hover throttle point, where the nominal values were calculated.

[wm175]

Again thanks for the advice I will do that and report back.

[wm175]

Ok my dynamic yaw hover percent I set as instructed in the setup video.
It’s .3687
Dynamic yaw max throttle is 1 I’m going to start by using .8. If I should be more aggressive in reduction let me know. As I don’t really know what qualifies as a high and a low number.

[wm175]

I went all the way down to .1 on dynamic yaw max throttle and It’s still wobbling at full power punch out.
When I say wobbling I mean the tail is ocilating fairly violently until I back off throttle then it starts to settle

[jihlein]

Did lowering that parameter help at all from your observations?

[wm175]

If it did it was not enough for me to be able to notice. Also when going full yaw and letting off quickly it wobbles back and forth a good bit.

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