Tello erratic movements

[Jace10110]

So I have my Tello for a little under a week. It was flying fine until the past couple of days. Now when flying for a minute or so, indoors, it makes sudden erratic movements and crashes. It will either just fall out of the air (looses power) or it will shoot up , hit the ceiling, and then fall out of the air. I have tried a few times to just take off and let it hover, but eventually I hear the motors speed up, and up it goes and hits the ceiling. On many occasions I did have warnings of low ambient light. That surely wouldn't cause the motors to speedup drastically or stop completely?? And I have seen warnings of the visual positioning system.

But now I have tested it in well lit conditions, without any such warnings and the problem still occurs. I have also carried out a calibration of the IMU. I even cleaned the downward camera lens with a cue tip and alcohol. So I am at a loss. I did connect it to my laptop via the DJITelloPy Python module to do some basic flight movements and image capture. Could such a session leave any trace of buggy code in memory (soz, grasping at straws here)?

 

[Brett105]

So I have my Tello for a little under a week. It was flying fine until the past couple of days. Now when flying for a minute or so, indoors, it makes sudden erratic movements and crashes. It will either just fall out of the air (looses power) or it will shoot up , hit the ceiling, and then fall out of the air. I have tried a few times to just take off and let it hover, but eventually I hear the motors speed up, and up it goes and hits the ceiling. On many occasions I did have warnings of low ambient light. That surely wouldn't cause the motors to speedup drastically or stop completely?? And I have seen warnings of the visual positioning system.

But now I have tested it in well lit conditions, without any such warnings and the problem still occurs. I have also carried out a calibration of the IMU. I even cleaned the downward camera lens with a cue tip and alcohol. So I am at a loss. I did connect it to my laptop via the DJITelloPy Python module to do some basic flight movements and image capture. Could such a session leave any trace of buggy code in memory (soz, grasping at straws here)?

Hi there Jace, try doing a full reset of the drone, hold the power button on for 8 seconds and start again. The Tello doesn’t perform the best indoors I’ve found, nor in low light, it has a hard time working out where it is, the sensors sound like they are getting mixed signals is my guess. It doesn’t hurt to do a calibration more often than not too, even if it doesn’t say it requires it to be done.

I was recently told by a technician at DJI that it’s good to calibrate the IMU each time you launch at a different location which I haven’t done in the past but will be from now on, that’s with the Air 2 I mean.

Anyways, good luck, HNY and Fly High…

 

[volate!lo]

IMU calibration is rarely an issue with Tello. It is an issue for larger GPS drones, as they have a true north compass which needs re-calibration for different locations (only if its a few hundred miles / kilometers from the last point of calibration or the last flight was weeks / months ago).

Indoor / twilight performance depends on the Tello model. The first Tello, the Tello Iron Man and the EDU / Robomaster versions perform well indoors. The later Tello standard model not so much. There is a separate thread about these issues somewhere in the forum, including good / bad serial numbers.



@Jace10110 There is one thing you can try: Get a new set of OEM props and do some indoor (!) flights to check if it fixes this.
If it's not the prop issue then your Tello is faulty: return the Tello to the store or contact Ryze for a warranty replacement. They may ask for log files (only present in the OEM app) as evidence.

It's an extremely rare issue and I read only a handful accounts over the years but as far as I know nobody has ever fixed a Tello with these issues.

The only video evidence I have ever seen of such incident indicates the barometric sensor gives wrong readings when the power-up happens. The drone continues to climb way past the 30m altitude limit until it runs out of battery and is typically lost, unless the battery was almost empty.

 

[Jace10110]

From what you are telling @volate!lo, I am now a little worried. I have carried out good flights outdoors with no problems since and have avoided flying indoors. I put the erratic movement down to flying indoors. But this could be merely coincidental and I was lucky it didn't climb to extremes outdoors, as you mention.

I certainly can't see any defects in the original props, but I do have a spare set unused I could try. I suppose I should stick to indoor flights for now to see if the problem occurs again. It would seem that ambient light conditions or issues to do with VPS should not result in a drone suddenly climbing or stopping.

 

[volate!lo]

Low light and VPS notifications are nothing to worry about. Tello simply starts to drift like a cheap $15 drone but that's all.

But if tello suddenly climbs by itself it's a hardware issue.

(And a few pirated versions of my tellofpv app can also cause this, so beware of any APK not coming from playstore)

 

[Jace10110]

Well I have been flying successfully indoors with no problems so far. If there is a problem I wish it would reoccur tbh, as now I run the risk of taking outdoors and it flying off on me some day. Apart from some hardware sensor fault, I wonder could interference from Bluetooth cause this issue, such as my Bluetooth controller Im using to fly it?

Anyway, Im having fun with this great little drone. I'm looking forward to trying out your app @volate!lo. I did have the notion that flying while navigating only with the FPV camera view would be easy. I even had the VR goggles ready to go, but I have learned it is too risky. I think the field of view is too narrow for that and I have managed to keep hitting obstacles. So back to line of site navigating.

Thanks for the tip about resetting the drone @Brett105

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