Mavic Mini Trouble / Ignoring input while traveling up and spinning.

[Zem]

First Mavic mini flight misjudged distance from a lawn mower so drone hit the handle of the mower and began to flutter toward the ground (emergency kill method by sticks in toward bottom center was applied.) To my surprise it rebounded up took back to the sky spinning up toward the canopy of trees 15 feet above. before it started too high I was engaging the emergency cutoff both sticks down toward center. While holding the sticks in this position it continued up hit the tree's and managed to flutter over a 8ft tall privacy fence in the neighboring yard. Does anyone know if there is a 4 second delay from when you actually have the sticks in the emergency cutoff position and the drone actually falls from the sky? I am curious why the drone ignored the request 4 solid seconds and somehow was continuing skyward. Drone had scuffs on rear left props but quite a few little scuff marks on the drone due to the 4 seconds it was flying itself out of control. This was mapped on the flight data where would I send this to have DJI look at the data? I have many flights with the Mavic pro and 2 pro without incident this is the first time a drone has ignored control well within range and continued skyward resulting in significantly more damage than should have been possible.

 

[Alex Baxter]

I believe there is a 3 second delay for CSC to prevent inadvertently killing the drone, but I'm surprised it did not just hover once you'd released the sticks, unless it had possibly started a RTH?

 

[Zem]

I believe there is a 3 second delay for CSC to prevent inadvertently killing the drone, but I'm surprised it did not just hover once you'd released the sticks, unless it had possibly started a RTH?

No it was about 20 feet from me no RTH was requested. My best guess is it detected hitting an object and it may have slowed a motor to a point it was attempting to recover itself and hover but it quite simply should not have been gaining altitude or spinning away while the control sticks were requesting it to shut off. It was exactly 4 seconds according to the log. It was flying perfect had 11-15 sats and no compass warnings. It was also on the latest firmware.

 

[Alex Baxter]

No it was about 20 feet from me no RTH was requested. My best guess is it detected hitting an object and it may have slowed a motor to a point it was attempting to recover itself and hover but it quite simply should not have been gaining altitude or spinning away while the control sticks were requesting it to shut off. It was exactly 4 seconds according to the log. It was flying perfect had 11-15 sats and no compass warnings. It was also on the latest firmware.

Plenty of people to analyse your data here, it'll be interesting to find out what happened.

 

[Zem]

impact with lawn mower appears to have occurred at 9min 12.5 secs. How it went from 2 feet to over 9 feet with both sticks in the shut down position is really a mystery.

 

[empennage]

First Mavic mini flight misjudged distance from a lawn mower so drone hit the handle of the mower and began to flutter toward the ground (emergency kill method by sticks in toward bottom center was applied.) To my surprise it rebounded up took back to the sky spinning up toward the canopy of trees 15 feet above. before it started too high I was engaging the emergency cutoff both sticks down toward center. While holding the sticks in this position it continued up hit the tree's and managed to flutter over a 8ft tall privacy fence in the neighboring yard. Does anyone know if there is a 4 second delay from when you actually have the sticks in the emergency cutoff position and the drone actually falls from the sky? I am curious why the drone ignored the request 4 solid seconds and somehow was continuing skyward. Drone had scuffs on rear left props but quite a few little scuff marks on the drone due to the 4 seconds it was flying itself out of control. This was mapped on the flight data where would I send this to have DJI look at the data? I have many flights with the Mavic pro and 2 pro without incident this is the first time a drone has ignored control well within range and continued skyward resulting in significantly more damage than should have been possible.

Other than a safety concerns, it sounds rather humourous... Things can go bad quickly and seconds seem like eternity when juggling..

 

[Bbarr]

I believe the sticks need to go down to the corners ,not center

 

[slup]

You didn't have the sticks in the emergency cutoff position for 4 solid seconds as you thought ... according to the log it was just a tad over 2 sec starting from 554,605sec into the flight ... at 556,703 you shortly release the sticks and reapply them.

 

[Zem]

I was noticing one part in the data where the left stick moved slightly left which probably reset the 3-4 second cutoff command. I had engaged the cutoff when it struck the object but released thinking it was likely eating grass with broken props. But then I saw the drone began going up and spinning with sticks in neutral which lead to the more significant crash scenario where I quickly engaged the shutoff procedure again. If the sticks were requesting it to go down what caused it to fly up so far and over a 6-8 foot privacy fence? The object it hit was not even 3 feet from ground level.

 

[slup]

I was noticing one part in the data where the left stick moved slightly left which probably reset the 3-4 second cutoff command. I had engaged the cutoff when it struck the object but released thinking it was likely eating grass with broken props. But then I saw the drone began going up and spinning with sticks in neutral which lead to the more significant crash scenario where I quickly engaged the shutoff procedure again. If the sticks were requesting it to go down what caused it to fly up so far and over a 6-8 foot privacy fence? The object it hit was not even 3 feet from ground level.

If you look at the green graph in the post above ... it was there roughly 2sec between the lowest height to the highest, then it started to lose height. Then the height it gained in the jump was just about above one meter.

With a damaged/disturbed prop from the hit the AC tries to compensate the lost thrust by revving up others ... together with your stick inputs that further confuses ... or mess thing's up. I don't think it's a big mystery, with a disturbed propulsion thing's like this can happen ... if you had been flying in a more open space the AC had been descended down in a spiraling motion (if the prop was damaged) & thing's hadn't been so dramatic.