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Anothe controller disconnect error

keat63

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Mavic Pro
After a short POI flight around my house, I initaied a RTH.
The RTH took over and started to acsend.
I relaised that the RTH safe height was much higher than my actual height, so I cancelled RTH and took over manually.
The craft was at a safe landing height of about 3 feet, straight in front of me, no more than 6 feet away from the controller, when a controller error occured and I lost control.
The craft then proceeded to ascend of it's own accord and moved back about 10 feet, so it was now directly above my house.
Luckily the controller re-connected and I regained control, and landed safely.

Any thoughts as to why I should get a controller error at such short distance.

Also, and I doubt that this be relevent, but 2 minutes after I'd landed a small aircraft flew over my house.
There was never going to be any danger of a collision, as I was flying at maybe 100 feet.
But it did cross my mind, could there have been say radio interference ???

Flight record attached.
 

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D

Deleted member 103366

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Ahhhhh there is a wonderful bit in the Mavic Pro manual,
"Aircraft will stop ascending and immediately return to the Home Point if you move the left stick in the aircraft reaches 20 meters (65 feet) altitudes or beyond during Failsafe."

Does anyone else think that is a bit odd?
Anyway what I think it means is that during the climb to RTH height if the drone's height exceeds 20m you can stop it from climbing higher and start it on the flight home by moving the throttle.

The Mavic Mini manual phrases it rather differently
"If the aircraft is at an altitude of 65 ft (20 m) or higher and has not yet reached the RTH altitude, the throttle stick can be moved to stop the aircraft from ascending. The aircraft will fly directly to the Home Point at its current altitude."

I know of this because I had a very high Failsafe RTH with the mavic mini, it climbed into connection but I didn't want to cancel the RTH until it was 'solidly' back in range. That section of the manual was pointed out to me.
 

keat63

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As it started to RTH to my pre set 50m safe height, I pressed the pause button on the controller.
At this point, I flew it manually.
As the craft starts to land, it always stops at a safe height of about 3 feet, where I then hold the stick to force a controlled landing.
It was at this point that I lost control.
 
D

Deleted member 103366

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Sorry let me clarify the reason for my post.
You said you had an excessive RTH height set, I was suggesting that it is possible once the drone was above 20m you could have stopped any further climb by fiddling with the throttle and that once that had been done the drone would fly towards the homepoint at its current height. I might be something to test and bear in mind, for any future excessively high RTH's.
I just found the wording of the manual odd since in a failsafe situation it possible that the drone would not be in contact with the controller at a height of 20m. I cited the Mavic Mini's manual for the revised? wording of the section.
 

keat63

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I see what you're saying but it doesn't quite add up.
I ended a POI flight by pressing RTH.
The drone now flying around 30m, started to ascent to 50m, which I cancelled with the pause button and took over.
I flew the drone manually to its home position.
It was hovering 3 feet from the ground, maybe 5 or 6 feet in front of me, when I lost control. (controller error displayed on my phone screen)
After a few seconds, the drone started to acsend again. I assume due to losing connection with the controller it went in to fail safe RTH.
Of course at this point, I no doubt panicked, and pressed every button, stick movement I could.
Maybe this was the reason, it went off course.
It doesn't explain the diconnect though and especially at about a 6 feet distance.

An excessive RTH altitude shouldn't have any bearings on what happened ??
 
D

Deleted member 103366

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An excessive RTH altitude shouldn't have any bearings on what happened ??
I doubt it.

My posts were an attempt to explain that if the drone has a connection to the controller you can, providing the drone is above 20m, terminate the climb to RTH height by moving the throttle. After terminating the climb the drone will fly towards the homepoint in the normal manner. My posts relate ONLY to the RTH climb, nothing else in your story.
 

keat63

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I've still trying to determine what's causing these 'remote controller dosconnected' errors.
Many theads all over the internet talk about it being caused by the USB cable, but I can rule that out, unless a cable is causing some sort of interference with the actual remote controller.
I've had these disconnectes with 3 different cables, 2 of which are brand new,and of these, the 2 new ones are pretty short, so ought not to suffer from any losses through the cable.

So I have the mavic pro in my front room with the props off.
If I remove the USB cable, of course the phone disconnects, but I still have control of the mavic.
The message I see on my phone screen is different to that when the RC disconnects.
Disconnected as opposed to ' remote controller disconnected'

Withe antennae folded in, the drone on my living room carpet, and me with my controller 20 yards away in my garden, I still have control of the mavic.
The internet is littered with posts and threads on this issue, affecting a whole range of Mavic devices.
 

eEridani

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I've had some odd RTH glitches with my Air 2 - but they are all probably operator error. Times when I thought I hadn't cancelled RTH yet did; times when I thought I cancelled RTH but I didn't. And if the drone is in RTH modes and wants to land, but you've taken over manual control of the flight, it still wants to land, but doesn't really want you controlling it to land - and fights control inputs.

Some of these events I've had it would be easy to think the controller has lost connection -- things just aren't working right -- but the controller and drone are communicating fine.

The UI is lacking when it comes to what is happening during RTH and all of the options you have to pause, interrupt, modify, tune, or cancel the function. Some of the problem logs here show drones in RTH seconds after takeoff, yet flying around as if in normal flight. Go figure.

ps: if the controller and drone lose connection, the log should show that happening. So what do your logs show?
pps: DOH - just looked at your log. lol.

When a drone is directly overhead, and you aren't pointing the antennas straight up at the drone, you are in a signal fringe area where loss of signal becomes possible, even likely. Many cases of people flying their drones overhead and behind them and when they don't turn and point the controller at the drone they lose signal. I notice that with my SC, and I have to flip the antennas so they point upwards, or the video goes choppy on me - but so far never lost signal within 50 feet according to my logs.

The antennae really are directional - and directly over them is the lowest signal strength - think cone of silence. The same is happening with the antennae in the drone. So you get a double whammy if you don't point the controller.

Radiation-pattern-of-a-dipole-antenna.-Antenna-is-oriented-vertically-along-Z-axis.png
 
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CDSkeeles

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Just to throw some noise into the conversation, I was having disconnects on my A2s where the camera and controls were lost but telemetry was still streaming. Craft went into RTH as expected and returned home safely each time. However I had to power down the craft and turn back on again in order to regain a full service connection.

I was also getting corrupted files on my sdcard. I have since replaced the SD card with a higher quality faster speed one and I have not had any further disconnects.

The suspicion is that the software running in the craft took issue with the card errors and would eventually crash the program (not physically lol) and lock that portion of the operating system up thus requiring the reboot.

As a test, remove card and fly without for a while and see if the problem persists. I was getting disconnect every other flight while using the bad card. Haven't had a disconnect since. (goes to knock on wood and realizes there is no wood in my office!)
 

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