Bad Quadcopter Motor | REAL WORLD BLACKBOX TROUBLESHOOT

[@prash3r]

At 9:00 "Motor number 4 is at 36% for whatever reason" actually tells us a lot more about the problem. It shows us hoch much thrust we get from motor number 1. If motor 1 and motor 4 are not delivering the same thrust the quad would spin around the Axis between Motor 2 and 3 resulting in a death roll. so the motor 4 is powered down by the pid to not cause that rotation. So they both need to deliver the same thrust in this situation. Its a good estimate to say that the ESC/Motor/Prop number 4 only delivers ~36% thrust

[@ricardoneves93]

Very good video as always, it helped me figuring out a problem in my 4 in 1 ESC. After seeing this video I have swapped motors, I have swapped arms because I thought they were damaged. I was already thinking that it might be the ESC, I just had no way to prove it. Thanks man, keep the good work!

[@julientourel6131]

Just brillant ! That could explain my lack of power. I will do the test. Thanks JB

[@matuka3755]

My tune was otherwise great, but I couldn't alleviate a persistent corner-dip on hard punch-outs - no amount of I or Anti Gravity or anything else quelled it. I'd had suspicions about the motors. This video helped me to use the black box data to conclude that a motor was indeed the cause. Thank you, Joshua - I learned something, today :-)

[@jakegarrett8109]

2:12 That's exactly what is happening. I do a punch out, and my quad starts tipping/dipping to one of the arms. Its not a little tip, its like, do a launch from ground and within 80 feet you've almost made a 90 degree turn. At 90% throttle its fine. I thought it was the motor (had 2 out of 6 DYS motors defective, one you would need a pipe wrench to turn), then I thought maybe its the ESC (of course its a 4in1 so I'd have to replace the whole thing). But now after hearing the PID loop should take care of it, I'm thinking its the flight controller... I recently swapped the receiver and haven't tested, so I'll see if that fixes it (previously micro receiver) .....................................Specs........................................... DYS Samguk Wu 2206 2700kv RaceStar 35A 4in1 RaceStar 5042 tri-blade Naze32 Rev6 (old and no blackbox). I might swap out with CC3D with blackbox BEC: AMS1117 with 100uF cap (800mA rated, its only running FC and receiver) 4s 1800mAh 65c battery but pretty old (I got some new 1500mAh CNHL 100c packs I want to test out) ZMR250 frame Misc parts: generic 1000TVL camera 600mW 5.8 VTX with clover antena iRangeX Tiny ^^ recently replaced by FS-iA6 (have yet to test) and a little Lego Space dude hot glued to the top with a control panel when my Go-Pro isn't on, cause you got to have character!

[@rotorgrrlfpv8568]

I used to work for a company that 100% specialized in making Tilt rotor quads, and can say you are 100% right about the prop wash issue... which is why companies like Tilt designed their frames to have the rear motors sit higher than the front motors to give them good clean air.

[@jamesellis5445]

That absolutely makes sense👍...Love the "Bardwellian" Logic Josh👌✌

[@charleswarwick4849]

I do really like this series. Love the data showing exactly what the theory suggested about the overshoot of the PID controller.

[@frankynathanael]

Thanks for this video, it really help me to troubleshoot which one is damage...

[@LAHover]

Glad to see you still poking around with BB videos :D I always enjoy these. Even if they recover things in the past, I find that new videos on them reminded me of things I forgot long ago :)

[@GroundControlRC]

Great information especially describing the weakest link on the power train and the effect on flight. Happy Flying!

[@akera9625]

....at min3:10: the bottom line is: flight controllers and overall these machines ar incredibly amazing!

[@Gho5tface]

Thank you! Exactly the problem I was troubleshooting this this week. And my blackbox log looks exactly like that, about 25% diff on motor 2-4 vs. 1 on full throttle.

[@kwadsavethequeen8305]

Great analogy. My mummy brain translates this to kids. Just because the parent is asking a kid to do something, it does not follow that the kid will or is doing it. The parents volume will increase at a common & consistent ratio the more the kid disobeys. I think parents need Blackbox logging!!!!

[@briankoch7041]

This the only reason i have sd cards taped in my racers. I look for the motor plateau when the quad becomes a pig. i replace 2 to 4 esc's for motors 1 or 3 weekly. I can't say i've ever seen a motor get weak (cooked magnets) or have so much friction to the point of a plateau.The other failure point is a trashed coil which just desync's. This includes motors i've flown with cracked magnets or trashed top bearings that were bare races. Typically there will be a lag that shows a wobbly peak in motor output that decreases to within 15% of the companion motor. It's possible i just haven't cooked a magnet enough to never get the rpm up to the companion motor but i've had several come down at 160f+ after a race. A quick field test is to rapidly arm and disarm with air mode or idle up active. The lagging motor has the bad esc. Also in the motors tab one can set the motor to 1100us then hit the home key and repeat starting at 1200us. Compare spool up response to the other motors. Lag or desync is a bad esc.

[@tsakali1977]

I just had an idea on the subject of better balancing the output from all your motors. You could theoretically see which motors are performing the best and place the best 2 on the rear arms, since the rear usually has to work harder under most situations.

[@HDgodfrey]

Love the gas pedal analogy! Sounds like you've driven my car!😁 Love it as always, going to "actually" use my Black box after work today. (First time) Can't wait to see it.

[@xavier_arthur]

When I apply full thrust, my quad sounds like a spark plugs are going bad 🙁 Ie: it's stuttering 🤷🤷🤷🤷??? Any suggestions????

[@DoubleA_AMAfpv]

Thank you Joshua Bardwell!

[@brianlink391]

Can't you use angle mode to diagnose motors? i.e. get into a stable hover, release the sticks and review that moment in the black box data to locate the outlier? I think it's a cool idea.

[@garrettalvarez2335]

Joshua, I recently had a bad DSMX Sat have a week channel on my Armattan Chameleon. After repeetedly reviewing Blackbox, replacing motors, esc's and flight controler the reciever was the culprate. Can you share your exsperiances on this topic. Thank you and keep being awsome. Your fan Garrett.

[@coastwiseable]

Joshua, Can you present a discussion on quadcopter ‘dihedrals’ ? Thanks, Joe Homer.

[@starshipfpv]

Thank you Joshua for all your help at kwad camp Houston 👍🏽😄

[@JoshuaBardwell]

Thanks for coming out!

[@hateeternalmaver]

Hey there, just wanted to say thanks. As always very useful information.

[@stevecaudle6075]

Can you hook a protocol kaptur to computer to find out why there's no power going to one of your motors

[@stevejakab]

Great video. Does it make a difference if Bi-directional DShot is enabled or disabled?

[@sburnham3]

This description explains how you could have unmatched motors and can fly.

[@Tavdog]

This makes me think that motor thrust imbalance could be a significant cause of throttle punch bobble. I know anti-gravity can help with the bobble but I still want to find the root cause and eliminate it. I've tried moving the battery around to adjust CG but that doesn't seem to change anything.

[@MrStevegibb]

How about running say slightly higher pitch props on the rear motors to compensate for the less clean air? I mean maybe say a cyclone 5046 on back and 5045 on front.

[@JoshuaBardwell]

It's an interesting idea. The responsiveness of the props would change so I'm not sure what effect it would have on handling.

[@thespencerowen]

If you have ESC telemetry, theoretically betaflight could detect the bad motor and put a warning on the osd

[@JoshuaBardwell]

Yep that would be pretty cool.

[@adrianryan1975]

Thanks Joshua.

[@hector-fpv]

Thanks Joshua, super useful!

[@properfpv7160]

Thank you Joshua! I did learn something today. Cheers!

[@Timsfpvshow]

Thanks for sharing Joshua. Very informative video

[@pateachongthu]

Whenever i disarm my quad (betafpv 95xv3) i see summary that blackbox : fault. What is the meaning of this.? Also, i noticed that the right rear motor is really hot that i can barely touched it, whereas the other motors are warm. Whats seems to be the problem.? Please.

[@tanahhuat1757]

Awesome video👍👍

[@MichaelAnderson2009]

Excellent video thanks JB 😀

[@hideovt6263]

sometimes it wasn't motor defective, in my case, run 3s rated motor on 4s lipo, desync all over the place, yet, once run back to 3s, no issue at all.

[@padroooo]

I see people checking motors with a meter but I never see them checking from the phase lead to the body of the motor. In other words the motor can be grounded to the carbon body frame. I have two motors in this condition. Any thoughts?

[@michaelbengtsson6416]

Thx for the video, it helps me alot. I probably have a defekt motor. Im no Blackbox-guru like you, but when showed how it looks like in the BB im pretty sure my motor is defekt. I just hope its not my Dalrc40a 4in1 😥

[@globaldesi2956]

As always great information But if we just lowered esc valueI(2000 to 1700 or 1600) of other 3 motors in blheli then it will balance it right

[@JoshuaBardwell]

No, I don't think it would. If you messed up the calibration on the other ESCs, the motor values in blackbox would change, but it wouldn't make the damaged motor spin any faster or make any more thrust, so the problem would still exist.

[@QBixFPV]

Joshua, Exactly what i needed thanks,

[@montypeak8417]

Thanks for the great channel! I have a motor that flies fine (I think) but doesn't twitch in startup like the others. Is that something to worry about?

[@KrotowX]

I'm more interested how you did got traces in log so smooth. Mine are way much more noisy. To be honest, didn't bothered about filters much :) FC's are softmounted, in some cases motors too.

[@TheLightningStalker]

Sample rate maybe

[@BroccoliBrigardist]

can desynch happen with dshot600? no right? copter of my buddy does deathroll, motor 2 goes 100% but it rolls over that direction so it just doesn't do anything he changed esc 2 and motor 2 problem still there is pdb or fc just damaged? cannot think of any other source and he has enough too fc is sp f3 racing clone

[@NetherViking]

Last! Dumb first reaction. Good job JB. Thanks for your vlog. 🤘😎

[@WrongWayFPV]

Dutchwalnut_fpv who cares about who’s first or last to comment.. you’re an idiot

[@NetherViking]

Because, what I wanted to say is that "First" is a immature reaction.... It's lame.. So that makes me an idiot?? hahaha Laughing hard at your face! :D :D :D

[@Ricpow80AkaNagamooto]

What does it mean if one of the motors drops to 0%? (my motor 3 drops to 0%, whilst the others are around 26-30% and then my quad falls from the sky)

[@olivierdudu6213]

very instructive

[@vitorxavier8257]

I recently changed my transmitter so when I crashed the other day I've mistaken the switches and it took me too long to disarm the Quad. It still flies but when I spin the motors with my hands it doesn't have the same clicking feel as it had before. Did I ruined my motors?

[@jordanbass3210]

Sounded like 5S audibly was it? If the quad was originally working fine and the motors were all working fine isn't the motor damage from a crash? How are you so sure it's defective or something was done wrong in the factory versus crashing and flying it? I honestly think this is more of a damaged motor issue than a defective one.

[@chrispychickin]

Here's a weird one that's semi related to the issue in the video: I have an asgard AIO, bh motors, well set up quad and no problems up until a minor crash the other day. First I noticed that it wasn't throttling down completely when I went inverted and chopped the throttle. Looking at BB logs, and there's one motor getting fed LOWER throttle signal than the other 3, all the time! I'm running dshot, so no calibration issue, and the board is physically in good shape on a component level. Any idea what could be causing a single motor to be running faster than the others at a given throttle, when all settings are the same? Tried stock PIDs just to make sure it isn't windup or something, but i'm totally lost at this point.

[@johnvodopier5318]

A very interesting video. I definitely learnt something today thanks to you. Keep up the great work and content. Cheers JohnV-FPV (noob) 👍

[@MultiShawnt]

ThanX , Pro ...

[@WrongWayFPV]

Good video as always.

[@dittobimaputra]

i just build my new quad. everything just default setting. cam and Vtx not yet installed....I just 1 st try to throttle up (quad rise) - move to zero throttle (really 0)...and rise up throttle slowly to catch several time. but actually when i rise throttle from zero to catch --> I can't catch them because the motor was driving like crazy they (motors) can not be controlled and ended by crash.. for ESC, i used FVT little bee 20A with one shot 125 protocol, damped light activated. bf setting => min command = 1000, min esc command 1020. what's going on sir ?, could you please help?. i will very appreciate your advance advice. thanks. ;)

[@dittobimaputra]

seemed the problem from throttle zero (all motor were down), and rise throttle slowly to catch... but seemed the ,motor were stall..during start again (uncontrolled)

[@luna95alan]

Josh I have a racerstar F4S tattoo Aio, i cant seem to get it to arm , it worked before but when i put status I get a Calib Flag. Is the gyro not working? It works when no battery is connected. I have tried moron threshold increase to 120 from 48 (stock) and flashed to latest stable and even reflashed a few times. Can you help please thank you

[@cyberpunkfpv3032]

I have one questions Josh! If one of my motors constantly maxed out on flat punchouts and other motors produce about 80% of trust in this time, woud it be vise to lower max throttle value in blheli suite for ALL motors to balance it out to the weakest, and woud it give more performance overall? Maybe more balanced behavior when pid controller dosent fight three other motors to fly it flat? That what i thinking! And no, i cant buy spare motor or esc righr now ;(

[@JoshuaBardwell]

You're not going to fix a damaged motor by adjusting the blhelisuite endpoints. It will make the blackbox traces look more equal, but that's just hiding the problem. The motor is making whatever thrust it can and it can't make more for some reason. If you can't replace the motor, then just fly and let the PID controller take care of balancing the motors.

[@elevatedfilm]

Nice video Joshua, I don't know if this is a question that makes sense but, the other day I think I damaged a motor a little bit,( shaft got a bit bend, but it still flies) it did not produce any vibrations but I did notice more wobble at the end of a punch out, as if i needed more I-term on both axles. does this make sense?

[@JoshuaBardwell]

It sounds like you need to replace the damaged motor :-)

[@superflanker07]

nice info

[@cptcrunch9090]

thx JB, my quad just started doing deathrolls last week... perfect timing on this upload... I did notice some "oscillations" when I would blip the throttle. 1 question, y should I keep old parts after replacement?

[@JoshuaBardwell]

Keep the old parts just in case they turn out not to have been broken!

[@jamesellis5445]

Joshua Bardwell here's that "Bardwellian" Logic again...❤it...it's Gold Really though....That's a "No Brainer" right there. ✌

[@xxtrengt8871]

Ok, so now I understand why my kwad was going so slow and then flipping to the ground But the thing is that in 3s it works pretty well (a bit slower than usual) and with a 4s battery it is terribly slow and then flip... Maybe the weight of the 4s battery make it want to run the motor faster and it max out Thank your for this educating video If you have an explaination to my issue I would be glad to hear it :)

[@JoshuaBardwell]

4S is making the motor want to spin faster which is bringing out an underlying problem.

[@sumukhas5418]

If I give a throttle input (very small) one of the motor speeds up and up to it's max and eventually flips before it could take off what could be the problem ?

[@JoshuaBardwell]

Board alignment incorrect would be my first guess.

[@sumukhas5418]

I have checked the motor propeller direction they look fine (according to the arrow on board) The motor and esc work (I don't know if they are defective) I have swapped motor it didn't solve the problem In motor output increasing the throttle rear right or front left motor spins crazy All these started after a crash it used to fly before

[@caradu9973]

hey JB I love you technical mind I think very much like you when we talked about the quad having to go forward or backwards we say that the motor spins faster but does it really spin faster continually or is it spin faster for a second or two and then equalize to keep that pitch because if they did continually spin faster it would just flip so it must only for a second spin faster to get that angle and then they spin the same speed to keep that angle

[@JoshuaBardwell]

It has to spin at the right speed to maintain the desired angular rate. So you're right that it spins faster to make the quad move then goes to whatever speed to hold the angular rate or position.

[@caradu9973]

Joshua Bardwell Thank you!

[@Gieffri]

Very useful video as always, but i have a question. I'm flying an fc wich does't have a blackbox, and i was thinking about putting a blackbox via UART. Is it worth it? I mean, would it record enough data to be helpful when troubleshooting issues like that? Or would it be useless due to the uart speed?

[@edwardshirleyCEO]

One of my motors keeps spinning then stopping, and it gets really hot, what is the problem in this case?

[@JoshuaBardwell]

I would guess the motor or ESC is damaged. Replace the motor. If the same thing hwppens then the ESC is damaged. If replacing the motor fixes it then the motor was damaged.

[@scrapsz1079]

What SD card do you recommend for the Bardwell FC, in order to do this blackbox monitoring?

[@JoshuaBardwell]

Just about any Class 10 card or higher will do. 16 GB is plenty.

[@the_real_foamidable]

Good stuff

[@WingStop1234]

Joshua how well does this compare to the motors test in Flightone, in your opinion is the test in Flightone pretty accurate?

[@JoshuaBardwell]

I have heard mixed results of the FlightOne motor test function. I'm not sure whether it is reliable.

[@dougbrokeit7406]

thankyou sir very helpfull

[@-Relectron-]

hello, i've got a special problem. Sometimes when i fly, the quad is having short twitches. i can feel it and also hear it too. is this a receiver problem or an motor/esc problem? Thank you for your time

[@JoshuaBardwell]

Most likely it is vibration or electrical noise getting into the gyro. Install a 330 uF electrolytic capacitor on each of the ESCs. Soft mount the FC. These sorts of things: anything that cleans up vibration or electrical noise may help.

[@dee1251]

my mobula7 is all wack and just turns to one side. I suspect its one or two of the motors defective, how can i test that? can i test it in betaflight?

[@sunshynff]

Does this happenwhen you arm it, causing to go berserk before you can even take off, or does it do it in flight after a maneuver?

[@brandonwoodford579]

Id definitely say 15% for sure is right on the edge.

[@domanater480]

Hey josh problem still persists with the death roll after high punch outs, zero throttle manoeuvres. i checked blackbox and it looks like one of the motors went to 100% after i zero throttled after punchout and seemed to roll towards that direction so it means the motor is defective? or was it just trying to compensate for the spin? Ive also noticed on the blackbox when i reduce throttle some of the motors will go to 0%?.is this something i need to fix with min throttle? Thanks a lot i really appreciate your time :)

[@JoshuaBardwell]

The motor going to 100% means that motor stopped making thrust. If it happens at zero throttle or the end of flips and rolls, consider raising digital idle percent in the Configuration tab (assuming you are using Dshot). If digital idle percent has to be above about 7% to 9% at most, then the motor or ESC is probably defective.

[@domanater480]

Joshua Bardwell alright I’ll raise that. Do I also need to raise min_throttle in CLI?

[@domanater480]

Joshua Bardwell I raised idle to 6% and put a new motor on to replace the apparent faulty one, Seems to have fixed the issue after 3 packs I couldn’t get it to do a death roll no matter what. Not sure if it was the resoldering, new motor or idle speed but all is good for now at least. Thanks again couldn’t have done it without your videos and help :)

[@charlescole5434]

Looks like you just finished a quad box video in the background there

[@ZigaBerce]

Hi Joshua, do you have any idea what could be happening here: ibb.co/iobQ47 Basically after the punch-out going into backflip (with zero throttle) motors kind of freak out. It's a 2" build.

[@gavsfpv3786]

legend

[@youeladamas7840]

lol this is not really about the vid though it was a good info drop Teach lol. do you find on rigs with a good size cap you get a little more power on demand and faster battery rise after punchout drains? i have been looking in to ecars and bikes and they use caps to help with burst power or are the caps we use just too small.

[@JoshuaBardwell]

No, the effect of the cap is way too small to be noticeable in resopnse to throttle punches.

[@youeladamas7840]

lol im going to try a 25v 22000uf cap lol its only 30mmx50mm you think it will give a boost or sag protection from amp draw . you dont need gopro in races but if it helps sag the battery can give its amps in a higher volt range thats the theory lol

[@InvertFPV]

Test the mr. steele v2's plzzz!!!!!!!

[@JoshuaBardwell]

He's over in the corner playing Zelda but I just asked him and he said they were the best motors he ever flew and you should totally buy some.

[@wickedreelz5028]

Just buy ya some F40 Pro v2s.. best motor on the market right now bar none..

[@InvertFPV]

I already did:) 2nd batch (Get the steele v2's)

[@InvertFPV]

The one thing is that, both me & Frosty FPV got one with a single messed up bearing out of the box. Over the process of arming and just sitting there listening to how quite & smooth they are, the problem seems to have disappeared, or at least minimized. Any Idea on why this is? They come with defective bearings that rattle when you spin them but the rattling goes away once you arm a few times. I haven't getting to fly them yet, waiting still on a armattan warranty part to come in:( But Frosty has and as far as he can tell, they fly perfect even with the ones with "messed up" bearings.

[@spacecowboyfpv5511]

Awesome

[@TheMadmacs]

i'm still struggling to simply use blackbox, i think this vid was a bit overly long, whole vid is, if one motor is always maxing out compared to the others theres something wrong with it. the really hard bit is getting onboard memory to record and then getting the traces up so you can see whats goin on. checking the blackbox log should be part of every new quads set up checks, but its not because its so vague to use. it should be simple, but as always its a half dozen questions a noob has no way of knowing or even guessing. log bitrate fc hz/ log bitrate per whatever onboard memory the fc has... these are the things we need to know. any idiot can see oh, that motors maxed out and surmise theres an issue.

[@JoshuaBardwell]

Please check out the Blackbox 101 playlsit in the video description to learn how to use blackbox.

[@whollymindless]

Damaged is not necessarily "defective". Don't hit up a vendor because you 'sploded. "Bardwell said it was defective"

[@jakegarrett8109]

One of my DYS motors came completely locked up (you might be able to turn it with a pipe wrench), and another had some slight housing wobble (bearing felt sloppy, and sure enough bearing screech is as loud as my props almost). Good thing I bought 6... These were on the Samguk Wu 2206 2700kv motors (only $10 a motor, but if 1/3 were defective, that's not that good). I've bought lots of $5 motors, and some were pretty nice, like those orange-gold and silver 2212 930-1400 kv motors and those things spin like a stealthy machine. Those have been great quality, not super race performance for my airplanes, but good consistent quality for just $5.

[@MCsCreations]

That's really interesting! Thanks a lot, Joshua! 😀

[@knightwolf8877]

huh that's so interesting

[@limitsizyasam3891]

You are super

[@theremalian]

7:48

[@TheLightningStalker]

0:44 😍

[@tch3rry1]

🔥💥🤙🏿

[@BuzZ.]

Noooo! You killed perfectly good damaged motor ! 😤 Lol 😂😂😂🐙😂

[@adronepilotcom7278]

I´m having a poltergeist with my quad due to over heat.....stops all engines and falls to ground...

[@GrulbGL]

weak ESC dude... and do not use spray oil on the board to remove humidity ;3

[@redlines2535]

wow, very interesting

[@3drccustombeasts381]

cant get past the voice