Greetings! I’m flying a 450 quad using PX4 with firmware 3.5.3 and Mission Planner 184.108.40.206.
First off, the quad flies very well: no problems with autotune, very stable, stays in one place with position hold, etc.
Second, the motors and ESCs (935kv and 30a ESCs) remain cool throughout a typical 10-minute flight.
My problem is this: I’m getting motor balance warnings and failures in the flight logs and it’s always the same pattern. Motors 1 & 2 are similar (on the low side), and 3 & 4 are similar (on the high side). Thinking maybe I have an ESC problem, I changed them out with different ones but the problem remains. Here’s the auto-analysis data from my last flight:
Size (kb) 12518.888671875
No of lines 146230
Firmware Version V3.5.3
Firmware Hash 1a85c237
Free Mem 0
Skipped Lines 0
Test: Autotune = UNKNOWN - No ATUN log data
Test: Brownout = GOOD -
Test: Compass = GOOD - mag_field interference within limits (14.01%)
Test: Dupe Log Data = GOOD -
Test: Empty = GOOD -
Test: Event/Failsafe = GOOD -
Test: GPS = WARN - Min satellites: 6, Max HDop: 4.2
Test: IMU Mismatch = GOOD - (Mismatch: 0.59, WARN: 0.75, FAIL: 1.50)
Test: Motor Balance = FAIL - Motor channel averages = [1458, 1512, 1595, 1615]
Average motor output = 1545
Difference between min and max motor averages = 157
Test: NaNs = GOOD -
Test: OpticalFlow = FAIL - FAIL: no optical flow data
Test: Parameters = FAIL - ‘THR_MIN’ not found
Test: PM = GOOD -
Test: Pitch/Roll = GOOD -
Test: Thrust = GOOD -
Test: VCC = GOOD -
The only other weird thing I see is the “THR_MIN not found” failure, but I don’t know what if anything to make of that. Given the pattern, I think we can rule out CofG as an issue.