Hey,
Today I crashed my quad and I'm trying to understand what's went wrong.
I was testing return to launch (RTL) mode. So I was able to get GPS lock.
When RTL mode was enabled pixhawk just flew away from me and crashed between trees.
I noticed interesting think from logs:
Log File C:/Program Files/Mission Planner/logs/2015-03-13 19-13-19.log
Size (kb) 645.455078125
No of lines 9390
Duration 6 days, 2:15:22
Vehicletype ArduCopter
Firmware Version V3.2.1
Firmware Hash 36b405fb
Hardware Type PX4
Free Mem 52816
Skipped Lines 1
Test: Autotune = UNKNOWN - No ATUN log data
Test: Balance/Twist = GOOD -
Test: Brownout = GOOD -
Test: Compass = FAIL - FAIL: Large compass offset params (X:-342.00, Y:-400.00, Z:-55.00)
FAIL: Large compass offset in MAG data (X:-342.00, Y:-400.00, Z:-55.00)
Large change in mag_field (140.55%)
Max mag field length (766.31) > recommended (550.00)
Test: Dupe Log Data = GOOD -
Test: Empty = GOOD -
Test: Event/Failsafe = FAIL - ERRs found: FLT_MODE GPS
Test: GPS = FAIL - Min satellites: 0, Max HDop: 2.09
Test: IMU Mismatch = GOOD - (Mismatch: 0.37, WARN: 0.75, FAIL: 1.50)
Test: Parameters = GOOD -
Test: PM = WARN - 3 slow loop lines found, max 9.38% on line 4002
Test: Pitch/Roll = FAIL - Roll (86.81, line 8128) > maximum lean angle (45.00)
Test: Thrust = GOOD -
Test: VCC = GOOD -
It is saying like GPS failed but I clearly remember that pixhawk was showing solid green light.
I will appreciate any help.
Replies
A simple test of the compass is hook it up to Mission Planner and see if the on screen orientation matches the direction. 0 is north, 90 is east, 180 is south, and 270 is west.
GPS is not the issue here. I have had RTL work with poor HDOP and you had 9 Satellites when RTL was started. With no GPS the copter would not use RTL and would have just went into Land mode. IE GPS failsafe.
Other issues would be that home was set wrong because of bad GPS at start. Checked that in the log it was also correct.
When you took off the copter was facing East and when you switched out of RTL is was facing South.
I havent looked at your log yet but, if you have logging enabled while disarmed you can get that error as the check/test simply looks for a low/zero sat count.
have tested in loiter prior to RTL? you need to test and have good loiter performance first.
Didn't test loiter yet. Will do it asap, need to print broken parts first (almost everything).
Wondering, can I change LED behavior/light like from green to something else if pixhawk get low/zero sat count.
OK, RTL uses the gps and compass so make sure your compass is giving good data with low offsets, do compass mot etc, and then test loiter. Check there isnlt any toilet bowling and its solid. Then all being well RTL will work correctly.
You will need to fix the compass issues shown in your auto test results above to get a good loiter.
Disable any failsafe RTLs until you have tested. Many fly aways are due to untested and fixed loiter performance when an RTL occurs.