# Error NOT_STATIONARY has occured during the flight.

Source: https://forum.modalai.com/topic/3338/error-not_stationary-has-occured-during-the-flight
Category: General Questions (https://forum.modalai.com/category/2/general-questions)
Posted: 2024-04-17 17:37:07 UTC by droen8
Replies: 5 · Views: 1339

## droen8 · 2024-04-17 17:37:07 UTC

Hello,

I've tried to test your voxl cam for the first time, first of all I've tried to leave a drone in the same position 2 metres above the ground for approx.15 minutes, drone held position very smooth and stable, nothing occured during this operation. Then I've decided to fly a little bit higher above the tree and unfortunetly I got some errors which forced that my drone switched from loiter mode to land mode as a failsafe. Furthermore situation appeared in the same way everytime when I've tried to fly above tree, which during the flight has a lot of moving points (like branch or leaves). Can you advise what could be a potential cause for above behaviour.

Below I attach link which reflects exact case.   
https://www.youtube.com/watch?v=b_4IsZeIQas (Error starts at 1;40 min )

Also.. You can see in the log that during the failsafe visio odometry cut down 
https://imgur.com/a/6DwytzS

https://drive.google.com/drive/folders/1BW4fhUM0Chb7pPKDekNavZtCjvXJfTE_ (All logs and videos are contained here)
FYI I am using ardupilot software

## Reply by Moderator (ModalAI staff) · 2024-04-23 03:54:19 UTC

@droen8 Hi, this is interesting as it looks like the features are tracking fine. Are you able to measure the vibration? 

[voxl-inspect-vibration](https://docs.modalai.com/voxl-inspect-vibration/) is a good tool for this

There are other VIO debugging tips here: https://docs.modalai.com/flying-with-vio/#troubleshooting-vio

## Reply by LaborzaubererTHI · 2024-04-23 12:32:32 UTC (in reply to Moderator)

@Moderator  This is a very interesting pose as we were about to post something very similar. We had two drones hovering. One dropped out just sitting/hovering there. 

Detailed description under the video: https://www.youtube.com/watch?v=H2JpUSIQqXA

Will take a look at vibration. But VIO in this outside location has been very unstable for us. On nearly every flight it VIO stopped working. 

Regards.

## Reply by droen8 · 2024-04-24 10:35:48 UTC

Hello Voxl Team, 

I've checked the vibrations during 15 min flight and it seems like they occur on accelerometer as it's reflected on the video. Please let me re-model my Voxlcam holder and get back to you.
 
Or.. Is there any other potential issue why those vibrations occurred. Gyro XYZ is stable however accel has them too much.

https://www.youtube.com/watch?v=jjCKZmrqrVQ

Regards

## Reply by LaborzaubererTHI · 2024-04-24 13:21:20 UTC (in reply to droen8)

@droen8 Your video is set to private. I can not watch it.

## Reply by droen8 · 2024-04-24 21:02:37 UTC (in reply to LaborzaubererTHI)

Hello LaborzaubererTHI,

You can see the video now as it has been set as unlisted. 

https://www.youtube.com/watch?v=jjCKZmrqrVQ

Sorry for that.

Regards