Copter crash after adding payload

ArduCopter Copter 4.0
1

Hello dear arducopter guys.

I have problem with my drone .

When i take off without payload (weight 6 kg), my copter flight stable without any problems 18 minutes.

When i put 2,5kg of payload (weight 8,5kg) something goes wrong and copter crash after 5 minutes of flight.

Only 2 legs was broken.

Here is log file from mission planner:
https://drive.google.com/drive/folders/1B5-6o6cGbvWh-jZUGlM0JG1DzBKrjqDQ?usp=sharing

Battery set is carged on 100% before every flight.

Have you any idea whats going on?

Thanks for quick answer.

My frame type is X

My setup is:

Hex Orange cube

Here 3 gps

RFDesign - RFD 868x Bundle Radio

Power Brick Mini

2x Tattu 12000 mAh 15C

4x APD 80F3x ESCs

4x T-Motor MN4014 Brushless Electric Motor KV400

4x T-Motor P17x5.8 propellers

TBS Nano Rx

TBS Tango 2 Radio

2

1st you have a mechanical Yaw bias with CW motors commanded higher than CCW motors. Then you had thrust loss on Motor 1, Motor 2 dropped to compensate and down it went.

RCout
RCout3366×1043 191 KB

3

Hello dear dkemxr.
What exactly you mean “you have a mechanical Yaw bias with CW motors commanded higher than CCW motors” ? Can you please explain it detaily what can be reason and how i can solve it?

Sorry but i am newcomer.

Here is log file without payload, when you look on it you see same problem with motors or it is only with payload?

https://drive.google.com/drive/folders/1cBH304qptcDmZTH-aLNtN3Mmq3IbE-8O?usp=sharing

Thanks for answer

4

This is usually caused by the motor mounts or arms being twisted (motors not vertical). The Clockwise motors are bening commanded higher than the CCW motors as a result.
I posted that graph so you can reproduce it. Graph the RCOUT’s for the 4 motors in the log of no payload. What do you see?

5

When i open log file (without payload) i see same.
Charts of Motor1 and Motor2 are upper like Motor3 and Motor4.

Normal flight
Normal flight1898×1000 187 KB

I check it tomorow with line laser.

Thanks a lot for quick help!
You save me !!!

1 Like
6

Have you any idea, why motor no1 loss thrust ?

7

That’s not usually apparent from the log. Motor, ESC, prop, connection failure. Could be any of them. Some may claim a desync but that’s no easier to prove.

9

Is any way, how i can identificate where is problem? Because i fight with this shit one year. I change esc from Hobbywing Skywalker controlled by PWM to APD 80F3x ESCs controlled by Dshot. What i can do in this case?

Thanks for answer

10

It’s unlikely to be an issue with the APD ESCs as far as I know.
As per the instructions for Compass/Motor calibration, I would:

  • Disconnect your props, flip them over and rotate them one position around the frame. In this configuration they should push the copter down into the ground when the throttle is raised
  • Secure the copter so that it does not move
  • Keep people and objects away

Then use MissionPlanner motor test to run all or individual motors until you see a problem.

11

When i put copter on this frame and secure it, can i make the same test, without doing any changes on props?

20230629_091459
20230629_0914591920×1440 701 KB

12

Yes, provided you can make sure the copter is secured to the frame and the frame is secured to the ground.