Mikrokopter Sudden wobbly roll (nick & roll up to 29 deg) during waypoint flight and dPH

[Dan M]

Third flight of the day with a CineStar6, and a fairly light payload (CineStar 2-axis gimbal and Sony NEX-5n), dead calm to light breeze, no gusts, 8-10 sats for GPS, running .88 nicely...
Up in free flight, dPH/AH/CF, then CH to start the waypoint run. Rock solid performance. I noticed one wobble mid-run, but nothing unusual.
Near the end of the waypoint run, the CineStar began to pitch around like a drunken sailor, with heavy GPS stick input causing nick and roll angles of up 29 degrees. The behavior continued when I stopped the run and switched to dPH flight.

That was about where my patience ran out, and I dumped back into free flight (instant stop to the wobble, since there was no GPS stick input anymore).
I brought the vehicle in, and landed softly on all three legs as if nothing had gone wrong.

Anyone want to take a stab at what could have possibly caused this? I'm baffled.
(I zipped the GPX file attached it to the post here)

-Dan

 

[Dan M]

Basic flight data in this post.
I'm actually starting to wonder if the LACK of wind could have contributed to the problem.

MikroKopter-Flight-Evalution:
=======================


Program-Version: 0.1.0.2
Supported up to MikroKopter FC-Version: 0.86
mdt: http://www.mdtweb.de
Wiki: http://www.mikrokopter.de/ucwiki/wemau
MK-GPX: http:///www.mikrokopter.de/ucwiki/MK_GPX


GPX-File: F:\Copter logs\20120419\GPX\GPS00002.GPX
Evaluted at: 4/21/2012 11:28:51 AM




Set-No. Description
--------------------------------------------------------------------------------


The GPX-File was read in
GPX-Version: NC 2.0
The GPX-File was output


Ini-File, GPXLogging ca.: 1000
MK-Version: FC HW:2.1 SW:0.88e + NC HW:2.0 SW:0.28i


The GPX-File supports the following Variables:
- lat, - lon, - time, - ele, - sat


The GPX-File includes the following "Extensions":
- FlightTime
- Compass
- GroundSpeed
- Altimeter
- Variometer
- VerticalSpeed
- NickAngle
- RollAngle
- MagnetField
- MagnetInclination
- MotorCurrent
- BL_Temperature
- AvaiableMotorPower
- FC_I2C_ErrorCounter
- AnalogInputs
- FCFlags2
- Course
- RCSticks
- GPSSticks
- TargetDistance
- TargetBearing
- RCQuality
- RCRSSI
- NCFlag
- Voltage
- Current
- Capacity
- ErrorCode
- unknown Extension: <WP> --> ----,11,13,0


Flight-Statistics:
- Starttime: 2012-04-19T15:37:33Z
- Stoptime: 2012-04-19T15:40:23Z
- GPS-Flighttime: 170 s, (2.83 min)
- MK-Flighttime: 168 s, (2.80 min)
- max. Height: 45.5 m
- min. Height: 0.0 m
- delta Height: 45.5 m
- max. Speed: 846 cm/s, (8.46 m/s), (30.46 Km/h)
- max. Target-Distance: 65.6 m
(PH: on, CH: on)


- max. Satellites: 10
- min. Satellites: 7
- max. RC-Quality: 209
- min. RC-Quality: 195
- max. RC-RSSI: 0


- max. Magnet Field relative to Calibration: 113 %
- min. Magnet Field relative to Calibration: 97 %
- max. Inclination: 71 °
- min. Inclination: 59 °
- max. Inclination difference: 3 °
- min. Inclination difference: -9 °


- max. used Capacity: 1974 mAh
- max. Current: 68.9 A
- min. Current: 0.5 A
- max. Voltage: 16.3 V, (LiPo 4S)
- min. Voltage: 14.7 V, (LiPo-Cell-Voltage: 3.7V)


- 6 Motors used.
- max. avaiable Motor Power: 255
- min. avaiable Motor Power: 250 (40 = Motor Restart)


- max. Motor Current: 6.9, 9.1, 14.8, 9.9, 15.7, 8.8 A
- Dataset number: 7, 1, 125, 104, 1, 1


- max. Motor Current: 1.5, 0.7, 6.9, 2.6, 4.1, 1.4 A
- Dataset number: 168, 168, 12, 8, 9, 139


- max. BL-Temperatures: 73, 56, 54, 56, 62, 38 °C
- Dataset number: 64, 64, 73, 112, 83, 35


- max. BL-Temperatures: 25, 27, 20, 27, 26, 24 °C
- Dataset number: 1, 1, 1, 1, 1, 1


- max. FC I2C Errors: 0
- no error occurred!


--------------------------------------------------------------------------------
77 Protokoll-Inputs tested.
168 Datasets tested.