Servers by jDrones

QuadPlane recovery from a flat spin


(rmackay9) #1

This video from Marco Robustini shows a real-life demonstration of a recovery from a manually induced flat-spin when using QuadPlane. The short form is to turn on the quadcopter motors by changing to QSTAB (aka “Quad STABilize”) flight mode.

Of course there are other cases where ArduPlane will automatically engage the multicopter motors which has been demonstrated in an earlier blog post.

(cala2) #2

Is better to change to qstab than qalthold? or is possible too? During an emergency we no need to take care where is the throttle stick, or is not a good idea? …Im anxious for my first flight coming soon :wink:

(Perth UAV - Sam) #3

Great video!

Hi cala

QHover is our standard recovery mode from any issue or failure in forward flight. I’m pretty confident that can be used in most QP airframes, provided they are not underpowered and can’t physically overcome the forces on recovery. It’s still advisable to have the throttle stick more than half otherwise the plane will descend or might not recovery in time.

Ideally setting up and using Q_Assist properly would avoid any stall from happening in the first place (apart from manual that is used in the video here to stall). Typically that results in no tip stall, and it will simply transition to hover the more it slows down if you have the forward speed set above the stall speed of the aircraft. Not as dramatic, but you should never see a stall again on a QP! This is the beauty of having two separate lift and control systems on-board at the same time. Either can fly the aircraft.

(Marco Robustini) #4

Hi all!
If “Q_ASSIST” is enabled and well tuned, the plane stall is impossible, especially if “Q_ASSIST_ANGLE” is set correctly.
In that video i will only to show how the copter can recover my VTOL in an instant without using automatic steps, and during an high spin of the IMU, compass and the other sensors inside the Pixhawk.
In that example “Q_ASSIST” is disabled.
I use the “Q_STAB” flight mode because in this case i preferred modulate the throttle manually, to not “strain” the structure too much.
The autopilot would reason differently and much faster.
The telemetry screen and on-board cam view may be useful to make some considerations.


(Ardupilot Dev Team)

(cala2) #5

Thank´s Jeff and Marco, nice to understand well this concepts before the first fly. I 'm going to dedicate enought time to tune the quad before do transition; I figure that only method to tune the quad is manually no?, autotune looks not possible; I’m correct?

(rmackay9) #6

I’m not the expert on QP but I don’t think copter’s autotune would do well on a QP because the wings will filter out the responses so it won’t be able to recognise when it has a good tune.