Tarot 650 flyaway issues on Loiter and slow response on sticks

I have a Tarot 650 with a Tmotor Velox 45A 4 in 1 ESC. Also, Tmotor 4006-13 740kv on 4s 5000mah with APC slow fly 12 x 3.8 props and Pixhawk 1. I have flown this drone a couple of times already. The time before this latest flight I did a autotune on the drone. However, I have some issues and if you guys could take a look at the log of my latest flight attached below that would be great. The problem is that when I fly in stabilize mode, the drone does not have any weird oscillation issues. However, when I switch it into altitude hold mode or loiter it begins to have oscillation issues or it seems like a power surge. I am not really sure how to explain it. It sounds like if you were revved the motors up and down like a car but I am at constant throttle. My lastest flight I had the drone in loiter mode and after maybe like 7 minutes the drone started going to the moon or flying away. I couldn’t control it. Therefore, I immediately switched it back into stabilize mode and I could regain control. The reason why I knew something was not right is because in loiter mode it wouldn’t even move that fast on full throttle. I decided to switch it back into loiter mode to see if I could recreate the issue and it happened maybe a few minutes later. Last but not least the drone feels really floaty and doesn’t move that precise compared to the motions of my fingers on the stick. If you guys could look at the log and let me know what is going on I would greatly appreciate it! It would not let me upload log because file is too big so I pasted a Google Drive link to download it.


What flight controller are you using?

A Tlog is of limited value. Post a link to the .bin flight log from the FC.

But from the extracted parameter file you have a bad tune:
ATC_ACCEL_P_MAX 73299.55
ATC_ANG_RLL_P 2.673435
ATC_ANG_PIT_P 11.28315

I am using the Pixhawk 1 flight controller.

Sorry about that here is an updated link to the .bin file. Thank you.


@dkemxr can you share how you extract the parameters from the .tlog file. And do you know how to do it on a .bin file?

Sure, Mission Planner will do it for both file types. For .bin log file the:
From the Dataflash Logs Tab select the “Create KML + gpx” button. It will extract a parameter file along with KML & gpx.
For Tlog files:
From the Telemetry Logs Tab select the “Tlog > Kml or Graph” button. Then from the Graph Screen select the “Extract Params” button and pick the log file.

The file format written from a Tlog is not as easy to work with as it’s in the order the parameters are loaded on boot (I think) and delimited differently. In any case if it’s all you have and you have a bit of work to do then I use Excel to re-order it.

Thanks @dkemxr that was all new to me :slight_smile:

This is good to know! How do I fix a bad tune? Do I just do autotune again?

First try to reduce vibrations - you have > 50 by VibeZ, this is to high level. According to https://ardupilot.org/copter/docs/common-diagnosing-problems-using-logs.html you got Vibration Failsave (SubSys 29 error). I had same errors on Tarot 650 frame, now i using DIY frame and very low vibrations level.

Second - before run autotune make carefully set proper parameters using this guide https://ardupilot.org/copter/docs/tuning-process-instructions.html
I am currently building 700mm quad and and i was unable to make it stable until i made all tuning manually as discribed in this gude.

Hello there! This is really helpful. Thank you very much! I guess the Tarot 650 frame is not very good. Also, I am not sure how I am going to fix vibration but I will have to figure something out. I did set the parameters before running autotune but I guess the vibration is just so bad it doesn’t work.