X8 pitches randomly plus issues downloading logs

Hello,

I’ve got a new X8 that I am currently getting set up. I’ve got it flying and it seems very stable so far in stabilize and loiter modes with the exception of some very random extreme pitching forward and left. It is very random. I’ve gone through entire batteries without seeing it then suddenly when it is hovering it will suddenly pitch left and forward. I’ve been testing fairly close to the ground so nothing bad has happened and it appears that it is recoverable in most cases. Each time it happens I can hear a change in the sound of one or more of the motors.

I’ve been attempting to get the log files to see if there’s anything telling in them but I get a timeout message anytime I try to download one. It begins the download but timeouts in the middle.

Any help for either of these issues would be appreciated.

jklier,

A little more info is needed.
What flight controller? What radio?

Sorry for not including that.

X8 with Pixhawk. Transmitter is a Turnigy 9xR receiver is a FrSky D4R-ii. Telemetry is with the 3DR radio.

One small update to my first message. the pitching is not limited to forward/left. On my last test yesterday it pitched once to the right as well.

After more flight tests I am thinking that I have a bad motor or ESC. While I mentioned that I did have a pitch to the right that may have been me (from the transmitter) as I have not had any other issues other than forward and left.

The X8 will hover beautifully for the first couple of minutes after a cold start. It always seems to take a few minutes for the problem to manifest itself. I am including a link to a video I made of the X8 sitting on the ground with me bumping the throttle a bit. Toward the end of the clip you can clearly see that the bottom, forward left prop does not always spin up with the others. This does not happen when I start the quad cold.

https://onedrive.live.com/redir?resid=52F52A79815DC8E0!2053&authkey=!AF23TKHQR7vd_ZA&ithint=video%2c.mp4

Any thoughts?

Please post a .bin log from the PIXHAWK’s SD card.

[attachment=0]31.BIN[/attachment][quote=“jschall”]Please post a .bin log from the PIXHAWK’s SD card.[/quote}

Logfile of last flight is attached. It starts twitching about midway through then has a fairly severe dive to the front left front at the end. It had flown perfectly stable for a couple of minutes prior to this flight. It follows the same pattern as before. It’s fine for a few minutes after a cold start but starts pitching slightly after a few minutes and gets more severe with time.

The 3DR help desk is sending a new motor and ESC as they are suspecting something up with the one that acts up in the video I posted. If anyone still wants to look at the log file I would still welcome any comments if it appears we are heading down the wrong path.

Yes, motor 5 is failing. You should also run autotune.

Hi jschall,

Thanks for the confirmation on that. I went ahead and replaced both the ESC and motor since I had them on hand and it did indeed fix the problem.

So from the logs you can see for certain it was the motor and not the ESC? If so I’ll keep the old ESC in my spare parts bin.

No - I can see that there’s something wrong with the signal wires, power wires, ESC, motor wires, motor or prop adapter. No idea which.