Testing to find the ULTIMATE BLHeli_32 Settings for 3" and 5" drones 

Where I can find this info?

@@cristian_c look at the mads tech video

Yeah, on my 3inch 24khz pwm was introducing jello to my 03. Changing to 48 fixed that. On my 5inch freestyle rigs, I run 24/24 and 03 footage is butter smooth 🤷🏻

@Chris Rosser I removed the propeller and got a log of rotating it to full throttle, and checked it with Betaflight Blackbox Explorer.The ESC is running Bluejay, and the vibration was the least at 96Khz.

This is why my recommendation has always been 48khz fixed timing. Based on my tests and reinforced by Chris's tests here, there are very minimal losses at 48khz and the noise reduction is definitely worth it. Above 48khz the losses compound and the noise reduction is not as significant and it's no longer worth it for 5" motors.

Your settings can’t have been that bad I’ve seen no changes in efficiency going from 23 degrees to 31 degree and 24 to 48khz. I found having a tune and esc in sync matters a lot

@@ironoidfpv I do agree, more minor tuning and changing things like props made a bigger difference, still great tohave this knowledge crystal clear in the mind!

and whoop motors, haha!

ESC drive mechanics are roughly the same regardless of the software. The same settings should apply in all firmware pretty much equally given the same motor and prop combination.

@@QuadMcFlyFlies as to my knowledge and my experience on AM32, your statement isnt completely right... as long as i know AM32 drives motors harder compared to BLheli, so PIDs has to run lower. Then everyone has different builds with different build quality and everything changes from quad to quad

@@gabruzz I've done extensive testing across all firmwares, going even back to the original BLheli 8-bit stuff before BLheli_S, and I've been testing AM32 since it was first released. I've worked closely with the devs from BLHeli and AM32 and I haven't seen any evidence for what you mentioned. Actually all the 32-bit software tends to run a bit lower at the top end than the 8-bit options, but that's not really relevant to what I am saying specifically here. The point is that the differences in these settings are roughly the same proportionally between all the firmwares and have the same basic impact regardless of the ESCs software. They're settings relative to the drive mechanics of brushless motor systems and the basics of that are the same regardless. The recommendations I mentioned above have been the same across several changes in firmware, BLheli_S/BlueJay and BLHeli32 for example. Obviously the tunes will need adjustment, but the settings recommendations are the same. As I mentioned elsewhere I do disagree with Chris on the recommendation for 24khz for 5" because of noise and tuning issues, but again that holds across all the firmwares I've tested.

Seems more relevant than 5 days ago doesn’t it

If changing flight controller software fixed your issue it was likely it wasn't a true desync, but likely something in the flight controller causing a dropout on the signal side. I've seen that happen more than once when the issue was actually a tuning problem causing runaway prevention to kick in etc. The thrust linearization recommendation is actually relevant to the decreased braking forces he shows here in his tests. It's important to note that the braking force losses are relative to the dead time multiplier necessary for each ESC, so will be dramatically variable depending on the ESC in question. Some ESCs with low dead time will not see nearly the degree of braking losses as ESCs with longer dead times. Typically the higher current rates the FETs the longer the dead time, and the worse the braking losses at higher PWM frequency. The more the braking losses the higher the thrust linear value is needed to compensate.

@QuadMcFlyFlies with the flight controller in question, the motor desyncs were occurring on default settings as well as after being fully tuned. After reviewing Blackbox logs, it was extremely similar to the desyncs I've seen in the past, where a single motor would go full power even if the stick command was not calling for it. Then, after switching to a KISS Ultra V2 FCFC, I pushed the tune pretty far and still did not have a single desync. The point is that just discussing ESC settings without including other factors like PID tune and firmware is just a strange approach, and it would be better to see a guide that ties the two together.

@@MurdersFPV I agree with you for the most part. I disagree with his recommendation for 24khz for this reason, as in many cases 24khz is unflyable due to gyro noise issues and 48khz almost always ends up tuning better. The research side of what the settings do is still solid here from Chris, but some context is definitely missing. I've tuned literally hundreds of quads and built and flown personally well over a hundred in the last 10 years, which goes into my recommendations, and I only recommend lower PWM frequencies for 7" and higher rigs as the dynamics change there a bit. Brian (PIDtoolbox Guy) will tell you the same things, I've worked closely with him to review a lot of testing especially for the larger motors. That's where the practical experience comes in to interpret the results in context. Would be nice to get some of that in the video.

@QuadMcFlyFlies This has been my experience as well.

yes

At 5" 48khz is 100% still the best recommendation. The braking losses are not that significant and the noise floor takes a serious hit at 24khz. Compare your gyro noise levels and you'll see you have to dramatically increase filtering at 24khz in the large majority of cases. You have to increase it enough that in most cases any handling improvement at 24khz is overwhelmed by the increased filter latency. I've consistently gotten the best flight performance at 48khz and very little filtering. This is why my default recommendation has always been and continues to be 48khz fixed timing.

you need much lower ramp up and much higher timing. infact your rampup and timing is exactly the worst combinatin for causing desyncs. try 25% rampup and 25deg timing. also i would not reccomend going lower than 24khz pwm. 16k causes lots of issues. 24k and good electrical filtering (lots of caps) should do. also never use non damped mode. it disables active breaking which is awful for the pid controller.

It's useful for smaller motors and lower current ESCs that have faster switching times and lower dead time values. 96khz and 128khz is super useful for tinywhoops for example.

@@QuadMcFlyFlies Agree, but I meant the ESC boards with 30.5mm hole mounting and not the AIO boards for Tinywhoops.

@@maryjane136 Yeah for sure, total marketing on the bigger ESCs other than the fact it likely means they have a faster processor, which is still useful for overhead even at the lower PWM frequencies. Higher speed MCUs tend to handle bidirectional dshot a bit more consistently in my experience.

I know, such a shame. Time to get on with the testing of AM32!

It still exists

Flash back to the original version

its either motor direction, motor mapping, fc orientation, or props. 100% user error. its the easiest thing in the world so solve if you just look it up.

Which settings can improve?