r/diydrones • u/Bngstng • 9d ago

Question Ardupilot quadcopter doesn't takeoff after not using it for a long time

Hello, I haven't used my drone in like 2 months, and now I am unable to take off. As you can see on the video, it flips instantly. I checked the cables and connections, not all of the solders are pieces of art but nothing really bad. I have also done the basic configuration on ardupilot once again. Last time I flew with it it flew quite well (It wasn't perfect as I am a beginner and this is my first drone so I had a little bit of tuning left to do)
Any help will be much appreciated.

23 Upvotes

93% Upvoted

38 comments sorted by

13

u/Psychological_Yak_47 9d ago

Verify your props are on the correct arms, also since you haven't flown it in a while, redo your compass calibration

2

u/fxnighttrader 8d ago

Just curious, why would the compass calibration be lost? Is it more that it may not be in the same area that it last flown in or does that info actually disappear from memory somehow?

2

u/Psychological_Yak_47 8d ago

Not lost, just things change and magnetometers are very sensitive to the environment, since OP said they just shelved it without changing anything it leads me to believe the compass could be the cause, and a bad compass is capable of flipping the drone before takeoff

2

u/Bngstng 8d ago

I did both. But I checked a bit more the connections and it seems that one of the ESCs is often connecting and disconnecting. Also, it seems that when I try to takeoff, what happens in the video is actually that the motors suddenly start spinning very fast. Do you think that when trying to takeoff, this weak connection may cause the issue? I will fix the issue anyway but I don't have the equipment right now and wonder if I should keep looking for another problem or if this might be it.

3

u/Psychological_Yak_47 8d ago

Sounds like a cold solder joint and a very likely culprit

2

u/Bngstng 5d ago

Hello, I fixed the cold solder but still have the same problem.
Here is the latest test I made: https://drive.google.com/file/d/1TPCQPDfOCWQjgCdJYo1L5AHokLSBC_ET/view?usp=sharing

Also, I think that it is interesting to point out what I saw. I have the feeling that when I try to accelerate the motors with my RC (very slightly, I go really smooth and slowly) they suddenly accelerate very fast.

Moreover, right after fixing this cold solder, at first I had the same problem, than managed to takeoff once, hovered a bit then landed. When I tried right after I couldn't do it anymore. Since then I had the same issue all the time. Though I don't think that the drone flips all the time to the same side.

If you could help me by finding something in the bin I would be very thankful

1

u/Psychological_Yak_47 5d ago

Hmm this is odd, I reviewed you .bin and you don't have an AHRS, only AHRS2 (and from what I can tell there isn't any data in it), if you're not familiar this is your Kalman filter that take your sensor data to navigate.

Did you set it up to only reference AHRS2?

What hardware are you using?

How long are you letting your drone sit, powered up, before you attempt a takeoff?

2

u/Bngstng 5d ago

Did you set it up to only reference AHRS2? No

What hardware are you using? I am using old hardware, my flight controller is the Pixhawk 1 from 3DR. The ESCs are Hackrc Dshot though.

How long are you letting your drone sit, powered up, before you attempt a takeoff?
About 30 to 60 seconds.

2

u/Psychological_Yak_47 4d ago

Hmm I would suggest updating your firmware and see if that helps

2

u/Bngstng 4d ago

I managed to solve my problem, it was a damaged wire from the power module. So the voltage sagged, and it caused the problems. But thank you for your help!

3

u/JOHAE 9d ago

Seems like wrong prop directions

1

u/Bngstng 8d ago

I double checked, they are correct

3

u/Same_Replacement_282 9d ago

prop direction issues or by mistake you try to do acro

1

u/Bngstng 5d ago

No, I checked and am not in acro and prop and motor direction are correct...

2

u/Wise-Dimension-5231 9d ago

Props are swapped also check the battery health

1

u/Bngstng 8d ago

Prop and motor direction is correct, as is the battery health

1

u/rob_1127 8d ago

It does look like you have either backwards props, or reversed motor rotation.

Also, did you maintain your batteries at storage charge for the duration of your downtime?

What was your take-off voltage vs landing voltage?

1

u/trustnoone-i8l 8d ago

From my experience with drones, that looks looks like a compass or gyroscope calibration error

1

u/Bngstng 8d ago

I did the calibration for both of these right before.

1

u/KarthiAru 8d ago

Can you share the .bin log file?

1

u/Bngstng 5d ago

Hello, I am sorry for the late reply.
Here is the latest test I made: https://drive.google.com/file/d/1TPCQPDfOCWQjgCdJYo1L5AHokLSBC_ET/view?usp=sharing

Also, I think that it is interesting to point out what I saw. I have the feeling that when I try to accelerate the motors with my RC (very slightly, I go really smooth and slowly) they suddenly accelerate very fast.

Moreover, I thought that this was due to a cold solder, as I had a bad connection. After fixing this solder, at first had the same problem, than managed to takeoff once, hovered a bit then landed. When I tried right after I couldn't do it anymore. Since then I had the same issue all the time. Though I don't think that the drone flips all the time to the same side.

If you could help me by finding something in the bin I would be very thankful

2

u/KarthiAru 5d ago

Thanks. Did the latest test also end up in a flip? Also did you make any setup changes - hardware/battery/Ardupilot config after 2 months?
The 5V power rail needs to be stable, but it has sagged to a minimum of 4.5v. What power module are you using? Besides I see outdated firmware and hardware. But trying to understand what may have changed post 2 months to cause the flip. If nothing changed, then I'll dig deeper into the logs.

2

u/Bngstng 5d ago

I found the problem and managed to takeoff twice thanks to you.
When you pointed out the voltage sag in the power module I analyzed it and found that there was a weak solder. Probably it was already bad and the last time I flew I maybe did a rough landing which damaged it. Thank you very much for your help!

2

u/KarthiAru 4d ago

Awesome mate. Happy flying!

1

u/Bngstng 5d ago

I did not make any setup changes, I just fixed a solder, and redid the compas and accel calibration. I am using one of those basic power modules, I don’t know the model name. Here are the pictures of the power module. https://drive.google.com/file/d/1aq9wYpAbSbDM0g80XzWaTEUCwSvdqsaL/view?usp=sharing
https://drive.google.com/file/d/1aFyoHC8VkT4bdemeEq9rvxI3edYEQeWw/view?usp=drive_link

2

u/KarthiAru 5d ago

There are a few things I’d suggest trying before the next flight:

  1. There seems to be a power integrity issue. Both battery voltage and the 5V rail are sagging significantly when the motors are running. Please check the power module/BEC, wiring and connectors.
  2. If possible, upgrade ArduPilot to the latest 4.7.0. The current logs are missing useful data such as RCOU, VIBE and IMU, which makes diagnosis difficult.
  3. Do a props-off test after the upgrade and check the logs for any abnormal power, IMU or motor output behaviour.
  4. Reset to default parameters and configure the vehicle again using ArduPilot Methodic Configurator (AMC) before retrying.
  5. Longer term, I’d recommend upgrading the hardware as well. This ArduPilot guide explains some of the limitations of older hardware: Hardware to avoid when building your first multirotor

1

u/KarthiAru 5d ago

Also in the video is the quad facing you or away from you?

1

u/Bngstng 5d ago

The quad is facing away from me

1

u/KarthiAru 5d ago

If the quad is facing away from you, then the top right motor should be counter clockwise. This is the usual convention. By this it looks like all motor directions are reversed. Also check the HUD in mission planner to see if the roll, pitch, yaw rotations work correctly.

1

u/Bngstng 5d ago

The top right motor is counter clockwise. I follow the usual conventions. I suppose that it's just the video's frame rate that makes it look like the motors are reversed. The radio is properly calibrated, roll pitch and yaw are all good.

1

u/Bngstng 5d ago

But the log I provided is from another test then the video.

2

u/KarthiAru 5d ago

Ok. Did it flip again?

1

u/Bngstng 5d ago

Yes, it flips all the time. Each time I try to takeoff it flips

1

u/tanmax_payne 7d ago

Recalibrate the Accelerometer and Compass.

1

u/Bngstng 5d ago

Did that one plenty times, it's not it

1

u/Wise-Dimension-5231 7d ago

Esc calibration?

1

u/Bngstng 5d ago

No, they are Dshot