MA gave me my first scare

[Deleted member 94047]

So I went out at sunrise this morning to try another hyperlapse. Flight was going well until about the 11th minute. The MA was going forward in TapFly mode at 1m/s snapping pictures every 5 seconds. And all of a sudden the horizon spins left and right, as if the MA was spiralling to the ground uncontrolled. A message appears about Obstacle Avoidance on screen for what appeared like a fraction of a second and disappears. I see TapFly trying to correct the orientation of the camera and fails, another message about TapFly appears on screen and goes away. I instinctively look up, well nothing to look at. The MA was 600 meters away, 80 meters up. I tell myself it is time to tell it to come home and I press the RTH button on the remote. Horizon goes through another few rotations at weird angles and I breath a sigh of relief as the MA rotates back and starts flying back to me with a perfectly level horizon. Birds? May be. Sun's rays? Most likely. All in all, glad it was just a little scare. Don't put me through that again please.

 

[skyrex]

I'd be putting money on sunight on the sensors making them play silly buggers..
Uploading logs from that flight for someone to analyse would be best to know for sure.

 

[Deleted member 94047]

You are probably right about sunlight playing havoc on the sensors. Logs show the MA going forward smoothly at 1m/s and suddenly accelerating to 9m/s while still in TapFly mode (I guess as OA kicks in) and then switching in to PGPS.


The event log is cryptic as usual (well, for me at least)

699.239 : 40076 [L-RC]Emergency break. rc vib!
700.001 : 40114 [L-SDK]app API sub_mode 2 0
700.001 : 40114 [L-MIS][NAVI MISSION] req sub_mode: Pointing off
700.001 : 40114 [L-SDK][USER]send ack 0x00
700.004 : 40114 [L-MIS][SDK] new open GS(cam)
700.004 : 40114 [L-MIS]received on/off 2 from dev 2
700.004 : 40114 [L-N_MIS]req abort all for USER.mission.request.off
700.004 : 40114 [L-MIS]ack on/off 0 to can
700.021 : 40115 [L-N_MIS]Switch new mis 3 req 2 from mis 26 req 16
700.021 : 40115 [L-FLYMODE]SWITCH2HOVER!
704.346 : 40332 [L-FDI][CTRL]: fault on , horiz_ctrl_fail
708.894 : 40560 [L-RC]rc cmd:STD_GO_HOME

The GO_HOME at the end was me.

 

[monty.roman]

I would also say front sensors got confused by direct sunlight. Doesn't seem like a bird hit since it would be more like a stumble, not spinning in several directions. What i was also thinking is the Compass error but that would show the warning which doesn't disappear in a fraction of second.

 

[Deleted member 94047]

My first reaction was "Oh ****! I got hit by a bird!". But, yeah, I think it was the sensors. For a second or two, it was tracking sideways as if wanting to figure how to go past the "obstacle". And then it went through a brief moment of panic as it tried to reacquire the horizon line on which TapFly was set to track. And then it switched to PGPS. And then I called it home and it breathed a sigh of relief. I think I will disable front sensors when flying towards the sun from now on.

 

[InvisibleName]

Happy ending though (phew!)

 

[monty.roman]

my Air also reacted to direct sunlight once or twice but never like this. It was kinda like a quick stop or hesitation followed by little change of direction (which still ruined my long straight shot anyway).

it doesn't happen everytime when you fly straight ahead, just when the sun is in certain angle coming through front sensors lens.

 

[GFields]

Glad you were able to recover!

A lesson learned "not to panic" but to "think" You recovered the MA because of clear thinking and not overreacting. Great Job!

 

[Deleted member 94047]

Glad you were able to recover!

A lesson learned "not to panic" but to "think" You recovered the MA because of clear thinking and not overreacting. Great Job!

Thank you for the kind words. On second thoughts though, I should have hit the pause button right away. Pause first, figure out what is happening and what to do next. I will have to learn that as my SOP for emergencies.