Loiter Mode, Took off stable, hover for 4-5 seconds, sudden Climb Up and Up and crashed

ArduCopter Copter 3.6
1

Log File C:\Users\Fahad\AppData\Local\Temp\tmpD2CC.tmp.log
Size (kb) 835.279296875
No of lines 10911
Duration 0:00:29
Vehicletype ArduCopter
Firmware Version V3.6.9
Firmware Hash 632be63f
Hardware Type
Free Mem 0
Skipped Lines 0
Test: Autotune = UNKNOWN - No ATUN log data
Test: Brownout = GOOD -
Test: Compass = FAIL - Large change in mag_field (1027.54%)
Max mag field length (2002.96) > recommended (550.00)

Test: Dupe Log Data = GOOD -
Test: Empty = GOOD -
Test: Event/Failsafe = GOOD -
Test: GPS = FAIL - Min satellites: 4, Max HDop: 4.58
Test: IMU Mismatch = FAIL - Check vibration or accelerometer calibration. (Mismatch: 7.07, WARN: 0.75, FAIL: 1.50)
Test: Motor Balance = GOOD - Motor channel averages = [1355, 1306, 1320, 1340, 1312, 1348]
Average motor output = 1330
Difference between min and max motor averages = 49
Test: NaNs = FAIL - Found NaN in CTUN.DSAlt

Test: OpticalFlow = FAIL - FAIL: no optical flow data

Test: Parameters = FAIL - ‘THR_MIN’ not found
Test: PM = GOOD -
Test: Pitch/Roll = UNKNOWN - ‘BarAlt’
Test: Thrust = GOOD -
Test: VCC = UNKNOWN - No CURR log data

1 Like
2

Hey! Post log. I think it’s probably because of high vibrations on z-axis. And move your magnetometer somewhere to less susceptible to magnetic field.
And how did you arm on loiter mode without GPS fix? Did you remove Pre-arm checks?

1 Like
3

Yes, it’s likely high vibration based on the “IMU Mismatch” message. There’s some advice here on the wiki regarding hardware solutions (which are the best solutions because it’s a physical problem).

Copter-4.0.0 includes a vibration failsafe which will hopefully help get the vehicle back home in one piece most of the time.