New Build - log file after first flight - what should I tune?

Dear ArduPilots,

Working on a series of all-weather capable quads. I’ve never really given much attention to tuning when building fixed wing planes because, I kind of just fly them… (‘-’)

I set up initial tuning as per the “Initial Tune Parameters” and the first flight was just perfect. I haven’t done auto-tuning yet, and only updated ATC_THR_MIX_MAN from 0.1 to 0.5 after the flight.

Ran through all modes during the flight. Stabilize, Loiter, AltHold, PosHold, RTL, Land. Landed perfectly in RTL mode (although it flew backwards to home)

It’s a 15", 4014 400KV, Pix6, 2x3S in serial, AP 4.5.7 MP 1.3.82

I’m viewing logs from the flight and deciding on what to tweak before the next flight.

Log file and params here: ArduPilot Logs - Google Drive

Any suggestions welcome

Yours sincerely, Johann Thor

MOT_THST_HOVER is 0.4074056

So I’ll set PSC_ACCZ_P to 0.4074056 and PSC_ACCZ_I to 0.8148112

Welcome to the forum Johann. You have several things to address on this craft.
1st, it is overweight/underpowered. The MOT_THST_HOVER is a hint but the RC Output’s at hover are the proof. What’s the take-off weight?
The vibe levels are high with X-vibes >40 which is worrisome. What frame do you have?
You have Dhot1200 configured, not advisable. Dshot600 is. But you are configured for PWM outputs so Dshot is not being used. What ESC’s do you have?
There are other things to ID here (motor ranges) but perhaps your best bet is to reset to default and start over with the Methodic Configurator
But, for sure you will have to adress the Thrust/weight and vibe issues before doing much else.

Thank you for your reply Dave

I haven’t weighed it accurately, I have a range of motors, ESCs, and batteries. This one is a bit on the heavy side, but I actualy intend to make it heavier. I’ve got more powerful motors, 16" and 17" props, and 16" T-Motor variable-pitch props also.

But this one is supposed to be a sort of middle-ground test platform to select different configurations going forward.

The frame is based on the CAD file for the HolyBro x650 - 3D printed with diferent lengths of motor arms. A waterproof aerodynamic fuselage, and many other changes. I have much more experience building fixed wing UAVs than quads.

Thanks for pointing out the Dshot1200. I have a Cube Orange FD with PX4 firmware, and I’m sure I’ve mixed up the setup on the Pixhawk 6X when configuring it previously in QgroundControl. I didn’t realize that I’d also set PWM outputs. I’ve got LEDs on MAIN and the Motors on AUX 1-4

The ESCs are Tekko32 F4 45A ESC but I also have four T-Motor AIR 40A ESCs that are meant for the third prototype. The Tekko’s do support Dshot1200 but I’d already ascertained from reading tips on this forum that I should rather use Dshot600

I already have the seemingly awesome Methodic Configurator. I did however opt to test, tune, and configure manually from the start to get a better feel for the whole process all te way through.

I’ll start with the vibe issue. I know what’s causing it. And do another test flight tomorrow with updated parameters.

So these are either BLHeli_32 or AM32, either way you should be using the Bdshot version of firmware for the 6X and configuring for Bdshot. I would bin the T-Motor Airs as old stuff…

Bdshot - gotcha!

Bin the T-Motor AIRs = check (I’ll use them for a volcanic eruption kamikaze mission in the future)

Thank you!

1 Like

This should be the latest and greatest

3/27/2025 11:27:53 PM : RCOut: DS600:1-4 PWM:5-8 NeoP:9-12 PWM:13-16
3/27/2025 11:27:53 PM : IOMCU: 410 2003 411FC231
3/27/2025 11:27:53 PM : Pixhawk6X-bdshot 00350049 3033510A 39343933
3/27/2025 11:27:53 PM : ChibiOS: 6a85082c
3/27/2025 11:27:53 PM : ArduCopter V4.5.7 (2a3dc4b7)
3/27/2025 11:27:52 PM : Frame: QUAD/X
3/27/2025 11:27:52 PM : IMU2: fast, high-resolution sampling enabled 3.2k
3/27/2025 11:27:52 PM : IMU1: fast, high-resolution sampling enabled 3.2k
3/27/2025 11:27:52 PM : IMU0: fast, high-resolution sampling enabled 3.2k

So far so good! If you have Bdshot configured correctly you should have ESC telemetry in the log.