Well boyz I really could use your input on todays flights.
I started with a normal flight. Just up and down the field… No issues. Flying like I was use to it flying.
The wind…AGAIN…started to pick up and since I Was nearing the end of the battery I landed. But at the last second when she touched down she pitched over on her back end. Not seriously but enough to have the two rear arms hit the ground. I disarmed it checked for damage and all was well.
Second flight I again up and down the field…but this time I thought I would see if I could get a bit more speed from her so I nosed it over and gave her some gas…it flew past me just great but then suddenly I heard my controller say… Vibration compensation on…I hit the brakes and she rocketed into the sky. I then heard GPS glitch and a few seconds later glitch cleared.
I brought the drone back with no issue.
Third flight started off good…I saw no issues in the first minutes of the flight…but my gut started yelling at me get low get low…so I brought it down low and suddenly she flipped over and went into the ground… I was ticked and started to walk towards it when I suddenly saw a ton of smoke coming up from the ground. I thought holy crap lipo fire and ran. I pulled the lipo and it was fine…IT was the left rear motor or esc…turned out it was the ESC…IT was SUPER burning…WOW.
Anyway. I have no idea what happened. The ESC is non existent now…IT burnt to a crisp. When I got home and pulled the motor mount…mostly black dust fell out…WOW.
Anyway if anyone can see anything odd in the logs I would appreciate your input.
My guess would be vibrations shook something in that motor pod around enough to cause a short, and that’s what went wrong your last flight.
I’m not confident to give log analysis, so will leave it at that.
I once had a short on a power distribution board on a sort of big copter… 10000mah 4s batteries. A short between the board and carbon frame started it. Then I think the short continued through the layers on the PCB… like, once it was arcing, it just kept going from top copper through the fiberglass board (or along the edge) to the bottom coppter… Anyway, I was inside booting up my ground control station, etc. Smelled the burning electronics and ran outside.
The PCB was just gone. A few of the bigger components were sitting on the ground below it. Inductor, large resistor, etc. But the board was gone. No ashes. Nothing. Vaporized.
I am leaning towards the same idea.
I notice that in this photo There is a screw that is covered in gunk. I didn’t check to see if it had come loose but it’s possible. What I did observe is that this screw in the photo corresponds to a massive hole in the ESC.
So perhaps, thats exactly what took place. What I don’t understand is the Vibration compenstation issue…But perhaps it’s tied to the same issue.
In your case I would assume the vibrations were real. Maybe that arm was vibrating on your high speed run and shook the screw loose.
That you could figure out by looking at the logs to see if vibrations really were higher when it popped up the message.
You might have seen the other post I made this morning about receiving vibration compensation messages when the copter isn’t even moving… But in your case, if it was after a high speed run, I’d assume the vibrations are real.
Heat sink won’t help if a screw shorts out the device. Thats the prevailing theory right now.
My only concern is whether the motor got damaged. I checked it with my multi meter…resistance is the same across all pairs.
I checked with an inductance meter as well and again the same across all pairs. I suspect the motor is fine. Luckily I have a spare ESC…I always order a spare. So this week I will replace and lock tight all screws mounting the motors just to be safe. Will also replace the ESC…just do I want to trust the motor…hmmmmm
so just grabbed my smoke stopper and powered up the quad…less the damaged esc and motor of course…but she booted fine. I checked the battery and it appears to be ok as well.
Battery reports 3.93, 3.98, 3.95, 4.00, 3.98, 3.90 all is 23.7
The log shows a current draw of 449 amps for less then 1 second. I suspect thats erroneously reported…but I will check all the voltage and current sensors as well. The list of to do’s gets longer.