Quad flips when powering up

ArduCopter Copter 3.6
1

Hey All, I’m not sure what’s going on here. I’ve set up similar setups many times successfully. I’m on 3.6.2 rc2 ChibiOS with a PIxhack v5. Props and motors are verified correct.

Everything checks out on mission planner as far as I can tell. It does the roll axis flip like motors A and B are not powering up as they should. It doesn’t matter if I’m on stab or poshold.

What steps would you take to trouble shoot this? I’ll post a log soon.

2

Motor and prop spinning direction is most probably the issue.
Edit: actually numbering, like which is motor 1 and so on…

3

I wish it was that simple, but I’m certain everything is correct regarding props and motor direction/layout. I’ve seen similar behavior months ago, and I fixed it by enabling the compass. This one has the compass enabled and calibrated.

4

On the pixhack, all ESCs but one can be unplugged from the FC, arm without trying to lift off and see which motor spins and direction. Then move on to the next.
Main out 1 = motor 1 = front right, counter clockwise
Main out 2 = motor 2 = back left, ccw
…as per http://ardupilot.org/copter/docs/connect-escs-and-motors.html#connect-escs-and-motors-testing-motor-spin-directions

5

I’ve tested in the motor test panel, and the motor assignments and directions are correct according to the wiki and layout. The props are correct. I’ve set up nearly identical rigs on pixhawk cubes and haven’t had any issues. Here’s a log2018-11-17 16-20-34.tlog (367.6 KB)

6

Have you got a .bin log instead of a tlog? Maybe set logging disarmed too before running another test, if you dare :frowning:

1 Like
7

I just checked an when I arm with props off, motors C and D spin up much faster than A and B.

8

I switched the motor outs to M1 2 3 4 from A1234 and turned off Dshot. That fixed it. @rmackay9 have you heard of Dshot issues on the Pixhack V5?

9

@vosair,

I don’t personally use DShot (yet) so I’m unfortunately not very good at providing support. Probably the best I can do is refer you to the wiki here. The only issues that I’ve watched be resolved by others is:

  • users attempted to connect the DShot to the flight controller’s main outputs but they must actually be connected to the auxiliary outputs
  • SERVO_BLH_MASK parameter set incorrectly (user set bits as if main outputs were being used but actually the auxiliary outputs were connected to the ESCs)
  • flight controller’s BRD_PWM_COUNT was set too high and needed to be reduced to 0 to make all the auxiliary outputs available for use with DSHOT
1 Like
10

I’ve had plenty of success with the cube. I switched to PWM on the M outs and it works fine. I also reinstalled the firmware.