Quadcopter flips and veers on take off

I am yet to achieve a successful vertical lift off on my first quad. I have everything in place, Compass calibrated, Accel calibrated, RC calibrated. ESC calibrated, Flight mode set to “Stabilize”.

I place the quad pointing to "North"
2. Power on the quad.
3. After the controller, Mission planner connect, I wait about 15 sec.
4. I arm the quad. Motors start to spin.
5. Just increasing throttle, the quad attempts to lift, Hovers a 2-3 inches up, veers to the East and flips over.

I suspected vibrations on earlier attempts, by analyzing the logs and indeed I can see it out of whack. So I damped them using foam and ear-buds and I got the vibrations well within range. Yet I see the same behavior as above.

I am using compass1 and compass2. I even eliminated a compass to see if it was compass issues. No change. I have pasted the auto logs from dataflash below:

Log File C:\Users\kirtiprabhu\Documents\Mission Planner\logs\QUADROTOR\1\2017-04-11 14-25-35.log
Size (kb) 1149.5849609375
No of lines 15245
Duration 0:02:14
Vehicletype ArduCopter
Firmware Version V3.4.4
Firmware Hash 73944917
Hardware Type
Free Mem 0
Skipped Lines 0
Test: Autotune = NA -
Test: Brownout = GOOD -
Test: Compass = FAIL - Large change in mag_field (42.31%)

Test: Dupe Log Data = GOOD -
Test: Empty = FAIL - Empty log? Throttle never above 20%
Test: Event/Failsafe = FAIL - ERR found: CRASH
Test: GPS = FAIL - Min satellites: 0, Max HDop: 99.99
Test: IMU Mismatch = NA -
Test: Motor Balance = GOOD - Motor channel averages = [1124, 1139, 1121, 1124]
Average motor output = 1127
Difference between min and max motor averages = 18
Test: Parameters = GOOD -
Test: PM = NA -
Test: Pitch/Roll = NA -
Test: Thrust = NA -
Test: VCC = UNKNOWN - No CURR log data

Can anyone please shed some light into this? I can attach the video/pic as well as the parameters and logs if required.

Thanks.in advance.

-Kirti

usually it’s an issue of motor and/or prop configuration;
do the motor test in mission planner: motors should spin from front right (motor A) to front left (motor D);
more info here

Thank you Panky.

I had tested the motors and checked the wiring. I am using the 4-in-1 ESC QBrain 25A with motors numberes as 1-2-3-4. Following the Arducopter motor sequence:

3 1
\ /
\ /
/
/
2 4

Motors numbering: M1, M2, M3 M4

I would assume I have to connect the motors to the respective PWM outputs 1-4 on NAVIO2, right? Meaning, M1- PWM1, M2-PWM2, M3-PWM3, M4-PWM4.?

If I connect M1-PWM1, M2-PWM2 and so on, and test the motors the motor sequence in the above diagram does not get followed. I had to swap M2 and M4 . Could that be the problem?

Thx
-Kirti

Reconfirmed, my motors are wired fine. Just as shown as in the sequence above.

RightFront - 1
LeftRear - 2
LeftFront - 3
RightRear - 4

Tested them through mission planner too.

-Kirti

if your usb-port points to the front, please post a log and the video;

It worked! I think my props were a problem. A couple of them were not fitted properly and were out of balance too. I changed the props and dampened vibrations further. It can take off vertically, so I had a few successful flights since yesterday. Thanks for all your inputs.

One problem though, although it takes of fine vertically, it starts veering towards the right . So for instance, Forward is pointing to North and after take off, it goes up fine, then starts veering towards East. If you see the attached i, the two red arms are facing forward. Will attach a video shortly.

2 Likes

“veering towards the right” means turning clockwise or drifting to the right?
stabilize mode doesn’t correct for position changes, but you can reduce your drift to a certain point by using save trim

  • use missionplanner to set up save trim to a channel of your pleasure
  • take off and use the trims on your remote to make the copter fly stable on a point; choose a no wind place;
  • land and activate save trim
  • deactivate save trim and put your remote controller trim settings to center again
  • repeat if necessary!

turning clockwise is another issue; in that case post your logs please, and a video

1 Like

I’m glad it lifted off!

Let’s make a separate thread on this issue? Post logs and video in the new one and I’ll move your post over there.