Crash help - possible motor/esc failure

[whoelseisbored (LiamHowe89)]

Hi guys,

Yet another newbie post! Hope they're not getting too much Haha!

Ok so I've been getting some sporadic cannonballs out the sky and it's really knocking my confidence in my quad - which really sucks and is making me hesitate when practicing.

Below is DVR footage of 4 crashes from yesterday. Initially I thought it might be down to the battery as none of yesterdays crashes happened on the first pack... until I hooked up the 1st pack again to test the theory and then it happened again (crash 4 I think).

The one thing I'm noticing is that when watching in slo-mo (as I included in the video) it looks like it's dropping towards the back right. Do you guys think the same? If so thoughts on what it could be?

The last time I had motor failure I took apart the motor and the individual wires had been damaged. That motor has now been replaced. Do you think I might have got a bad batch?

[badger1]

oh dear, that's a pain. 

I did notice that in 3 of the 4 cases, BF was reporting Min RSSI of 0% - I wonder whether it was disarming on signal loss & causing you to fall out of the sky?  is this the same quad where you chewed up your Rx antenna?  or is the quad just not set up to report RSSI to the FC?

I think to troubleshoot it properly you would need to put an SD card in the FC slot & turn on blackbox logging so that if when it happens again you can really see what's going on in the FC.

if a quad drops one corner consistently, then my suspicion would be on the motor/ESC for that corner though.

[whoelseisbored (LiamHowe89)]

Yeh I should have mentioned that I hadn't setup the RSSI reporting on the OSD properly. It shouts it out on my T16 when I flick a switch so not too much of an issue at the moment. Strength is fine as well since I replaced the Rx antenna.

This is my FC and I don't believe I can check the blackbox as there is no SD slot

[badger1]

hmm, I'm not sure there's any other way of getting the blackbox logs without an SD card slot.  you might just have to swap out components - motor, ESC, etc. - one at a time until you figure out what's at fault.

is that bad corner the motor that was full of mud the other day?

[whoelseisbored (LiamHowe89)]

hmm, I'm not sure there's any other way of getting the blackbox logs without an SD card slot.  you might just have to swap out components - motor, ESC, etc. - one at a time until you figure out what's at fault.

is that bad corner the motor that was full of mud the other day?

Damn thought that might be the case Guess it's back to it, not what I was hoping for when I saw the weather forecast for this week

Nope that was the left front that had the mud in it, kinda wish it was so I had a clue as to why. What's more annoying is that I don't have any spare ESCs to test so means I'm gonna have to wait for that to come and unless I change them all that means waiting for China. Lol.

Do you remember it being this much of a pain when you built your first quad? Lol.

[ched]

Couple of things, the RSSI on the OSD seems to flash then you failsafe. When the quad is falling you can see the OSD giving you a flight time etc, just like when you disarm!!! So it looks to me like something is causing a disarm - i.e. a failsafe.
So I would double check that the new antenna on the rx is the correct fitting (FrSky have 2 different fittings and I guess an older antenna will fit a newer rx but wont connect properly. There is very little between them maybe 0.5mm diameter. It might be worth taking both off and checking against each other.
It is also very worth while to have rssi set on the osd and switch on Warnings on the OSD and drag it to center so it's in your face if you get a warning.

I couldn't see on your FC but some have BlackBox onboard you just have to set it, but it's not a massive amount of storage.

I don't think it's an esc or motor!

As for difficult when starting - OH YES. I built my first quad almost 5 years ago https://youtu.be/qpZdNL00lX4
The FC and software (CC3D using OpenPilot) by todays standard was terrible. You needed to be able to fly to set PIDs as stock were so bad. Unfortunately I was trying to learn to fly so it was a vicious circle!!!!!
In fact it was so bad I gave up for a year, sold/swapped the quad for a F450 (10" props DJI Naza FC). That enabled me to learn on as it was easier to see, had gps and it moved a lot slower than a 5"  . I flew that for a year then built a Martian 3 details : https://www.multi-rotor.co.uk/index.php?topic=21681.0
I have not looked back since        My flying isn't very good at all but I enjoy it and is coming on very slowly but then again I have never been a gamer so my eye hand co-ord is a bit slow       
 

[badger1]

Do you remember it being this much of a pain when you built your first quad? Lol.

just to make you feel better lol:

[whoelseisbored (LiamHowe89)]

Yeh so the RSSI on the OSD can be disregarded as I don't think I've set it up right. It reports to the TX fine and the flight time coming up is me having a habit of disarming as soon as I know it's coming out the sky.

The RX antennas are all good, did a load of range testing before going out and no problems at all tbh.

I'll have a look to see if I can enable blackbox somehow. It does show as a tab in BF but I imagine that just shows up regardless.

Glad to know it's not just me! What's annoying is that for me it doesn't seem to be the act of flying that's the issue, I'm progressing with that just fine, putting the odd flip in etc but it's the quad just not wanting to play along. I know bad workman, blaming tools etc but it's really freeking annoying that I can't get through 2 packs without it buggering up somehow

I think one thing I would recommend to anyone coming into this would be "buy at least 2 extra of stuff like motors and escs etc". Because the wait time from China is a royal pain.

Nice LOS flying there

As a side note... do you guys tend to use Airmode or not so much?

@badger1 Eww haha. Was that self inflicted or a technical? 

[Bad Raven]

This is my FC and I don't believe I can check the blackbox as there is no SD slot

I bought one of those and rapidly wished I hadn't!  Total Carp!!

I have quite a few of the Matek F4 FC's, esp the one with the ribbon to the matching PDB (they keep changing the name/number!!).  All of these (7 if memory serves) have all been easy to set up, worked well and continue to work well.

[ched]

As a side note... do you guys tend to use Airmode or not so much?

Airmode is needed for flips and rolls as it helps maintain fc control over motors when throttle at zero. It can make landing a little bumpy unless you are quite gentle. I used to have horizon, Rate+Airmode and Rate on a 3 pos switch. Then as I was coming in to land switch to just rate mode without airmode.

[Ern Stock]

Yeah , I only fly in rate , with airmode on a switch.
Switch on just before take off , switch off just before landing.
Basically I use it as a throttle up switch. It does help when throttle chopping on a descent.

( I grew up on open pilot / cc3d too ! Aaaah the nostalgia !)
 

Ps to OP - yup , at times it's a continual diagnosis & fix fest.
Other times it's all flying.

[relativenewbyseb]

I couldn't help but think on crash number 2, the groundsman going 'not on the square!' [emoji23]
And sadly I can't give any advice as haven't had quite the same happen to me, but hasn't been plain sailing
I leave airmode on and just get close enough to the ground to disarm, the only times it's been an issue is taking off if I try and do that too gradually

Sent from my VOG-L09 using Tapatalk

[badger1]

Eww haha. Was that self inflicted or a technical? 

ahem - pilot error 

I fly with stab/acro/air in a 3-pos switch.  I generally fly in air mode, but switch to acro for landing.  I have stab mode on there in case video fails because I can't fly acro LOS 

[whoelseisbored (LiamHowe89)]

Thanks so much for all your replies guys!

I've done a bit more testing.

Hooked up to BF and manually raised and lowered each motor as I did the last time I had an issue like this (last time it was the front right motor). I found that occasionally the back right motor would just go nuts and fail to rotate fully. Basically the same issue with the last motor. I'm starting to think that I may have had a bad batch of motors... either that or they're really really fragile! These haven't really been heavy crashes at all.

Luckily when I bought my last motor I bought 2... so will get it swapped and see if that makes a difference.

With regards to Airmode... thanks again for all your advice. I initially had a 3 pos for angle/acro trainer/acro but that was mainly while I was getting used to my rates etc. I think I'll change it to the way @badger1 has it as that seems most logical.

I really hate landing in Airmode as I'll always touch down relatively smoothly for it to bounce and flip

I bought one of those and rapidly wished I hadn't!  Total Carp!!

Damn... unfortunately I bought this FC while following a build from UAVFutures. For the most part it's been ok but until you get into the build and the hobby properly I don't think you always know what you should be looking out for. I do like how it has the FC and PDB in one as this is such a compact frame that I'd struggle to separate them. That's for the next build

I couldn't help but think on crash number 2, the groundsman going 'not on the square!'

The owners had just left so got away with it

It is also very worth while to have rssi set on the osd

Been looking into it and apparently with the R-XSR I have to setup the TX to send the RSSI info to the FC. Didn't realise this! I'll get looking into it today!

[badger1]

Been looking into it and apparently with the R-XSR I have to setup the TX to send the RSSI info to the FC. Didn't realise this! I'll get looking into it today!

here's how to do it on FrSky:

[whoelseisbored (LiamHowe89)]

Haha I knew Bardwell would have a video on it somewhere! lol.

Cheers

[ched]

To add to the complication, if you want. You can flash fw to your R-XSR that will enable you to use F.Port. Connect the (non inverted F-Port - very small solder pad on rx) to a tx pad on FC and that provides full telemetry back to your tx - with only a single wire as you can get telemetry with an extra wire from S.Port. So you can have voice alarms for voltage levels etc. If you added a gps you can log that data on your tx and copy it to a pc and then see your flight overlay on Google maps.....

I would wait a little while before changing rx connections and too much telemetry  I was just giving you a little indication of how powerful the r-xsr and OpenTx is 

[whoelseisbored (LiamHowe89)]

To add to the complication, if you want. You can flash fw to your R-XSR that will enable you to use F.Port. Connect the (non inverted F-Port - very small solder pad on rx) to a tx pad on FC and that provides full telemetry back to your tx - with only a single wire as you can get telemetry with an extra wire from S.Port. So you can have voice alarms for voltage levels etc. If you added a gps you can log that data on your tx and copy it to a pc and then see your flight overlay on Google maps.....

I would wait a little while before changing rx connections and too much telemetry  I was just giving you a little indication of how powerful the r-xsr and OpenTx is 

Tbh that's the plan eventually. I like the idea of having GPS enabled on it so I'll look into that when I know the thing is actually stable! Haha.

Just followed JB's video and RSSI now showing on the OSD

Now to swap out the motor lol.

[whoelseisbored (LiamHowe89)]

Motor swapped for the new one and all good it seems!

Finally flew 2 packs without any technical ballsups

The flying wasn't anything great and there's a few things I'm learning to avoid (propwash etc). DVR video below for anyone intrigued 

[ched]

Looks good, well done. I remember when I was able to achieve a full pack without crashing I was very pleased 
Your batteries don't seem to last very long. What are they? They seem to be a bit low starting out at 16.0v (4.2 x 4 should be more like 16.8V).

Where I normally fly (well back in Feb) it's just an empty field and I used to take things to put down so I had targets to fly round. Even if it's just a few ground markers like they use to practice football with like these Marker Cones. That way you learn to be more accurate and gain more precision control. I would say throttle control is the most difficult especially balancing throttle when doing coordinated turns to remain level.
Keep up the great work and keep vids coming. It will be great to look back over your progression.

[badger1]

very nice  is that recorded with the onboard DVR on your AKK VTx?

those sight screens are just begging to be flown through   

[whoelseisbored (LiamHowe89)]

Cheers guys

@ched Batteries are Ahtech Infinity 4S 1500mAH & Turnigy 4S 1400mAH. The first looked a bit lower because I'd been testing the motors with a bit of LOS first 2nd... used it for testing again earlier in the day and forgot to boost it back up again Although I'm convinced this one (Ahtech) has 1 cell that's a bit naf. Always lags behind on the balance charger.
Been looking for things to put down tbf and now I know (fingers crossed) that it's capable of lasting a couple of packs then I can start to work on accuracy etc
Think I might just make a progress thread and keep posting videos haha.

@badger1 It's on my Skyzone 02X's, doesn't look the best and res is a bit low but it will do for now My VTx is an Eachine 805 but when looking at the AKK one it looks exactly the same haha. Assuming Eachine is just the Banggood version or something?

[badger1]

@badger1 It's on my Skyzone 02X's, doesn't look the best and res is a bit low but it will do for now My VTx is an Eachine 805 but when looking at the AKK one it looks exactly the same haha. Assuming Eachine is just the Banggood version or something?

ah, sorry, I must be confusing you with someone else.  the DVR quality on my Skyzones is a bit ropey too - nothing like as good as the actual image I get in the goggles.

[whoelseisbored (LiamHowe89)]

ah, sorry, I must be confusing you with someone else.  the DVR quality on my Skyzones is a bit ropey too - nothing like as good as the actual image I get in the goggles.

No worries haha. Tbh I'm not too fussed, was never planning on doing much with the DVR other than using it for my own reference. Yeh the image in the goggles is wayyyyy better haha.
I get the impression the DVR isn't much better in Fatshark's either.