KISS v. Betaflight on a 9"-2.2Kg QUAD 🤔 😮

[@uavtech]

Folks, KISS logging does not seem to work right or provide useful data. I tried to get logging to work - and did - but only at the slower baud rate (115,200) so the logs were not useful. Even if not all chopped up for a 1k logging rate (500hz logging rate started to not be as chopped in the traces, but it still was pretty chopped) it doesn't carry the Rate type through in the Header, so your Setpoint in the log (the sticks or target you are comparing to) is all blown out of sorts so logging is kind of useless. Especially when you have no target and can't record at a rate above 250hz; which is too slow to analyze any gyro noise to see how mechanics are looking and how filters are doing.

[@jackiefpv1678]

If you cannot have Kiss's logging to work with 250,000 baud rate, I think you have to update your logger. I had the same problem and updating the logger's firmware solved it.

[@uavtech]

I have OpenLagger. It works fine on BF at 250,000 and 2,000,000 baud rates. Maybe since you cannot set the KISS baud rate, other releases have 250,000 hard codes vs 115,200??

[@jackiefpv1678]

@@uavtech you can change the baud rates to 250,000 in the config.txt file in the logger. Its defaut rates is set to 115,200.

[@chrishiggins7475]

Great in depth but simple how you explain video again Mark 👌

[@yannickg6904]

This video made me want to hurry up and finish my 7in build. I'll be using an SP Racing H7 Extreme board, Kiss or FETtec would have been nice too, but I got the board for cheap.

[@tehllama42]

I have three cheap beater 7" setups, and I can tell you they work out just fine. Get it in the air, work up towards a filtering scheme that lets you run 1.3 or higher P&D gains, and then just shred the skies, because those are awesome.

[@yannickg6904]

@@tehllama42I'm almost done building it, I got a little sidetracked and started flying an Acrobrat. My 7in build will be on the lighter side, with only 2407s and Biblades. I'm aiming more for efficiency than all out performance. I'll be able to tweak the KV with motor output limit, the motor's stock KV is 2600. It will be on 6S, so I'm guessing around 1300kv (50%) should be a good starting point. Can't wait to try it. I'm waiting on a GPS unit and a Lost model buzzer to be delivered.

[@princesfpvdrones]

Well, I started with Betaflight and haven't tried anything else but I haven't any need to try KISS. Thanks for all the explanation!

[@Shroomania]

Have you tried the DAL foldable props?

[@uavtech]

Yup. They work great.

[@h2o-fpv623]

great video thank u my kwads are 5 in i have 3 and im building a 3in going to see how that one comes out.

[@mike216ism]

I tried one of my kiss quads after months of sitting. I have to say betaflight is leaps ahead. They have come a very long way. With rpm filters and proper tuning it is like nothing else. My motors stay cold on these hot summer days and the precise sound is second to none. I can actually hear a perfect filter tune. Hope all is well Mark. You have given us all the best tune possible. There's no way I can do what I do without your videos

[@heggy_fpv]

how much do props affect the tuning? can you get a good tune that would work on shitty off-balance props (but show up in hd footage) as well as on super balanced smooth props?

[@uavtech]

Props are everything. You need good props for a decent tune.

[@heggy_fpv]

@@uavtech can we tell good props from bad ones when looking at blackbox? I mean, I know for sure which of the 7 inch props are real bad on my quad, cause all is shaking in hd footage, but with "good props" it is hard to see which are better.

[@uavtech]

@@heggy_fpv , yes, you can compare on Blackbox easily.

[@heggy_fpv]

@@uavtech yep, tested today, the noise is definitely more pronounced on worse props

[@McDaniels777]

...flying FPV and fighting with insects...that's pure adrenaline rush 😁😎😂😂

[@nonplayercharacter9653]

Great video Mark. Maybe this is why I heard Kiss is designed for and works best with 5" specifically. You really need the adjustability and proper logging when you get into the non-standard stuff.

[@uavtech]

It helps for sure. The main issue is KISS doesn't have i-Term Relax. That is it's dowenfall here.

[@sros25]

Nice tune dude! Good stuff 👊

[@jamesparkerfpv435]

I suspect if the quad had modern esc's with rpm filtering, that it would cure the issues. I'm no expert and fairly new to all of this, but it seemed like poor motor authority was battling you throughout tuning. and RPM filtering has seriously made all my quads fly so amazing! thank you for that feature, so much.

[@uavtech]

RPM would help. The APD new Firmware does support it. They are advance ESCs for X-class, but needed to catch up. Owner is going to flash up. This quad showed strong 2nd harmonic (echo) of main motor noise that RPM would help tackle.

[@Dzejwor_Gromowladny]

Do same thing for 5inch quad - please :D but people who think that only kiss flies good, doesn't need any tuning and hits gaps and make dives himself. they will say it's a hoax. But I like to laugh at them sometimes, one even cursed me and stopped flying with us 😂😂

[@BikeGuyFPV]

And this is the reason I moved away from KISS and started using Betaflight. More tools in the toolbox to work with and tweak with as well.

[@zdkama]

Nice video. I had a somewhat similar experience tuning my 5" kiss build. That said I think those P-gains are way too low, basically half what I run on a 5". The defaults are 3/.030/10. What made you take P down? Isn't the advice in your own PDF to increase P gain for slow bounceback? You also said you didn't want to take the gains any higher because hot motors but you totally disabled TPA. Doesn't that also help a lot with temps? Particularly in the propwash range -- which really heats up motors. It seems to me that without i-term relax the P/I balance is a thing you need to worry about as well, and yours I is too high for that little P.

[@uavtech]

Anything higher P-gains and the quad would overshoot - with i-Term set to 0.0001 - so that was the correct PD Balance. Lowering the I-term might have helped reduce the i-Term bounceback, but the fact is even with 100 D-term Setpoint weight there was still a sufficient delay that you had i-Term Windup and artificially reducing i-Term to cope with not having i-Term Clamping as a tool is not a good way to operate.

[@zdkama]

It looks to me like things got worse when you used 100 setpoint weight, which is also what I experienced with kiss. I run it at 65 now, with higher P and D gains than I would otherwise. For a while it looked just like the 2.75/0/20 tune. As I said I think the P/I balance actually matters when there is no i-term clamping. You're treating the I-term here as an independent variable and without clamping it doesn't function like that. Whether that is better or worse is debatable but that's just how KISS does it. I don't think we can tune P/D balance in isolation here like in BF since the i-term has such a strong effect.

[@HayBeseret]

Thanks for the video ! What a pro like yourself thinks there is in KISS that handles propwash so good ?

[@uavtech]

I think it handles the same as BF,F1, iNAV, Emu, etc...

[@brianevans4]

Betaflight really does have some great features! Just out of curiosity, what motors did this build use? And how come did you have feed forward set so high? Thanks

[@uavtech]

Brotherhobby Avenger V2 2813 I think. Looks like they are listed as 1115KV. I can't see in pics I have and I shipped back.

[@edouardmalot51]

thanks

[@logo8009]

I must say my Kiss v2 fly's better than any BF quad I have had. May I ask what your Kiss setup is? What version v1 or v2 and esc's? Also mine is only a 5" and any time the d's get over 16 it's really causes issues. I have never had a Kiss quad fly that bad.Thanks for sharing.

[@uavtech]

V2, APD ESCs

[@logo8009]

That be be the big difference as I run Kiss esc's but they don't make them for a 9". Thanks sure sharing. You have BF tuning locked in! @@uavtech

[@logo8009]

@@uavtech I will be waiting for a 5" comparison. LOL

[@Josa1984]

I might be off. cuz o just half ass looked at this video.. but why did you run that on soo low P on the Kiss?? That P gain is almost like running low 30ish P gain on betaflight

[@Josa1984]

And btw.. i always have my old kiss v1 alien as a reference point when i tune my betaflight/emuflight kwads and i cant get them to FEEL as good as my KISS kwad... and i dont know wy?? Even tho the KISS have 3 years old parts.. The Kiss feels locked and smooth/snappy at the same time... what can i do on betaflight/emuflight to get that feel?😟😅

[@uavtech]

Can with any higher, it had P-term bounceback (overshooting). And KISS gains are not the same scale as BF.

[@uavtech]

To get the same feel, turn off FF and stuff and tune it in BF or Emu. KISS just uses ad standard PID controller like BF or Emu.

[@starsstripesjacket]

Random question, does KISS have 3D mode? Ive never looked into kiss because last time i checked they didnt have 3D mode and i suck at flying 2D :p

[@uavtech]

Not sure. But I think no.

[@starsstripesjacket]

@@uavtech thanks

[@WKfpv]

Pretty sure it has 3d since dshot came out

[@mchevalier77]

How was it on the BF default tune? This video was real interesting to me as I've been tuning a 9 inch lately.

[@uavtech]

Needed adjustment. Generally on a 7"+, P and D gains need to be the same or inverted (P lower than D) and you need higher PD gain strengths (60 to 70 gains).

[@tehllama42]

In short, big quads on BF defaults are 'wandery', just kinda feels rubbery and struggles in easy flight. Quick fix, as described.

[@heartpilotOB]

I'm first? Off topic, are you using R9 or 2.4GHz? Why have you not migrated to crossfire? Just a thought. Edit: wait I saw CRSF

[@uavtech]

Yup. I'm on CRSF.

[@heartpilotOB]

UAV Tech super 8 antenna? But why? Just migrated from R9.

[@uavtech]

I just migrated to CRSF too. Some stuff was captured with my R9.

[@CorrexPoE]

i got a question too.. Why CRSF? im using xm+ on all my quad and i dont have issues, why would i need to spend more money for something i dont need?

[@FailsafeFPV]

@@CorrexPoE You most likely don't need it, however It does offer features that are nice to have, and it can go very far

[@HERSDT_FPV]

19:03 not so smooth

[@uavtech]

Yeah, mean on the sticks.

[@MouwDown]

Dang, Betaflight for the win here. I wonder why so many people rave about Kiss on a 5" setup? More smooth or way less prop wash on kiss than betaflight. Idk

[@biggfpv2721]

I thought u can log with kiss? Can't you hook up a logger I always thought you could

[@uavtech]

I tried. It worked, but only at 115200 baud rate. Too slow to get 1k logging rate. Plus the header data missing for rate type is no good.

[@roscotte]

Yes, you can log on Kiss with an external logger, like a RMRC Black Box Recorder for example.

[@uavtech]

@David Cooling, ever try it? I have the OpenLagger; the most advanced logger i know of that can capture up to 4k rates with BF. On KISS, it would only record at 115,200 baud rate which means only like 250khz logging rate. Too low and rates are missing, so Setpoint is blown up. In BF, the Lagger records at 4k logging rate with no issue at 2,000,000 baud rate.

[@roscotte]

@@uavtech Not recently, I have a RMRC Openlog, but I will try later because of a new Kiss setup.

[@uavtech]

@@roscotte , let me know if you have any success. Two hurtles. First the logging rate. 2nd it not recording the Rate type in the Header, and hence Setpoint (the target --- the sticks) is not there and you really kind of need a fast rate for noise analaysis (1k+) OR the Setpoint for tuning. So without both, yeah, not helpful.

[@RubyS.1]

I'm going to take the "oh that's not good" put it on my arm/disarm switch.

[@baughaninastorm]

Have dozens of quads on BF but fancied a change. Built a Kiss quad, don't know if I'm set in my ways but it flies like crap. Can't get anything like a tune out of it. For me at least that was a waste of £50

[@uavtech]

I think you can flash BF to the KISS board.

[@baughaninastorm]

@@uavtech thank you, 👍 I saw that. Looked at options and Kissv1 seemed supported up to 4.0.6 and kiss V2 seems like it has support on development build 4.3 but I can't seem to find any information what might need tinkering with to get it up and running.

[@HERSDT_FPV]

22:25 kiss much better

[@uavtech]

Really? Look at when KISS had proper PD Balance to.not have overshoot. Sure, you can crank P gain (first flight on KISS) for better wash. But then you get bounceback which is no good. So you need best ALL AROUND, no just one time stamp in video.

[@j.finesseflights1403]

I'll tell you what a "well known" pilot told me.... Get smoother on them sticks! Smh!

[@uavtech]

Rates were the owners.

[@j.finesseflights1403]

I agree with you! There should be smoothing options? KISS has its advantages but slow to try new things?

[@pkvillager]

This seems like a weird first KISS vs BF test for anyone... How many people run over 6"? Why no filter tuning on KISS? You are set to medium when you should most likely be at high. My 5" can run Medium in the cold but I'm on medium-high for summer. but I think its a combination of the temps and my motors being more worn. I've run BF for years and it is at its best right now for sure but I liked Helio better until 4.x and now I am on KISS/FETtec and I'm never switching back. The only thing I miss on KISS is onboard BB logging but I haven't needed it because for my 5" KISS flew 99% perfect out of the box. BF flies 85% out of the box but following your tuning guides can get it perfect in 2 packs but I still like the feel and control of KISS better.

[@uavtech]

Tell me what High means vs. Medium and we can talk.

[@pkvillager]

@@uavtech Oh come on, you cant be serious

[@uavtech]

Seriously.

[@pkvillager]

@@uavtech man you really have a chip on your shoulder for anything other than BF if you are pretending to not know what high, medium and low mean. I basically spam reddit on BF tuning questions with links to your guides too, so its not like I'm some kind of KISS fanboy...

[@uavtech]

No chip. Just want someone to explain. I'm not sure folks know what is what. kiss.flyduino.net/dwkb/kiss-fc-oscillations/ So you think for a 9", i should have applied less filtering (higher cutoffs)? That doesn't make sense to me since larger quads have lower motor noise peaks and therefore lower cutoff are appropriate, especially for larger quads where it is more key to push up the D-Term. KISS is a standard PID controller with Setpoint Weight. They don't filter the RC input so it makes all kinds of irregular motor command spikes. I'm not seeing the attraction. I really tried to make it work here and it became obvious to me it just could not. It can't push a quad to really track the stick close for racing and for lower power to weight quads, it lacks i-Term Clamping to avoid I-Term bounceback. No logging to boot. Why would anyone pay more for less???

[@Aridrona]

I wouldnt trust kiss on a long range quad

[@uavtech]

Why not?

[@Aridrona]

@@uavtech from what ive seen from friends and a few vids , kiss seems to fail alot. Could be the setup they had or poor build quality. Ive never ran kiss gear tho, little gun shy..

[@zfpv7211]

Aridrona I run Kiss on 5”, 6”, and 7”. Zero problems. I think the ESCs used I. This video probably didn’t help the tune on either platform. But I’ll say one thing, my 7” started life a Betaflight quad, could not for the life of me get it to fly without some sort of artifact. Got annoyed and thru a FETtec FC on it, flew perfect on basically defaults. It’s a never ending argument of opinions and preference. Betaflight guys say the BF flies better, kiss guys say the same. I started on BF and once I found Kiss I never looked back. BF just feels robotic and noisy. Kiss is smooth like a river. That is my preference, so that’s what I prefer. Not to mention the ease of setup to perfect flight, 1/10th the effort of Bf. No need for logs when things work right.

[@zuldanfpv4634]

Ive never had a Kiss FC or ESC fail on me.

[@eduenlamer]

Wouldnt trust anything but kiss for long range tbh. But hey, preferences... The kiss 32a esc's are the only esc I would ever put on anything flying in a non retrievable location.

[@Quick-Flash]

You didnt know that kiss has logging?

[@uavtech]

It doesn't work right. I have the OpenLagger; the most advanced logger i know of that can capture up to 4k rates with BF. On KISS, it would only record at 115,200 baud rate which means only like 250khz logging rate. Too low and rates are missing, so Setpoint is blown up.

[@FinalSlice]

@@uavtech you can change rate in text file 🤦🏾‍♂️