I tried using my Mini 3 Pro during the night, and the drone flew itself to the left without any input. Is it expected behavior or is something wrong with my sensors or drone? I remember flying the drone during sunset and in the air till it was dark and landing home safely. I tried troubleshooting it in the house with lights on and off, but when the lights are on the drone works perfectly but when the lights are off during its flight, the drone moves left / right and if I switch the lights on, then again the drone slowly stops moving
Find the attached video

with my previous mini2 drone i used to fly and land outside through the window of the room. once when i was landing in a dark room, the drone was thrown sideways into the furniture. i guess it didn't see the ground... but i'm not sure what the mini 2's bottom sensors are.. .they will be different from mini 3

Had enough satellites been received?  

Can you check the log file to see what the drone received, which stick movements, etc. pp.   

Everything looks good for me, no joystick movement and satellites are also  .. below is the log

Log

Mirec5050 Posted at 6-3 22:22
with my previous mini2 drone i used to fly and land outside through the window of the room. once when i was landing in a dark room, the drone was thrown sideways into the furniture. i guess it didn't see the ground... but i'm not sure what the mini 2's bottom sensors are.. .they will be different from mini 3

Does this happens to your mini 3 pro as well?

summit_explorer Posted at 6-4 01:38
Everything looks good for me, no joystick movement and satellites are also  .. below is the log

Loghttps://youtu.be/5aWhvLT7rRQ

Before the flight took off it gave you IMU error, were you aware what problem it can land the drone into?

The Mini 3 IMU (Inertial Measurement Unit) is a built-in device responsible for keeping the Mini 3 level and stable in the air, by monitoring the drone’s velocity angle, force, and attitude.
This is done by checking the Mini 3s accelerometer, barometer, gyroscope. If any of these systems are out of whack, and not corrected, your Mini 3 could:

    Tilt while hovering
    Have difficulty remaining steady and stable in the air (this is what was happening in from of your eyes)

Second warning it gave "Ambient light too low Obstacle avoidance is unavailable" & more over it doesn't have side sensors, only front & backward facing sensors but they could not work as ambient light too low.

So basically drone lost its own orientation & became blind due to darkness.

All you had was pause button on the RC to stop it completely but in the moment you forgot to hit that button.

summit_explorer Posted at 6-4 01:59
Does this happens to your mini 3 pro as well?

I've only had it for 2 weeks, so it hasn't really flown yet, but I've already found out that when I want to fly out the window, I have to turn off the sensors in the menu!

The low light may not help, as the bottom vision sensors need good light to work effectively and would need to rely on the much lower preciseness of the GPS to hold a position, that coupled with buildings hiding a  good view of the sky would have lowered the number of sats viewable from the drone's position, all in all, i think that the drone believed that it was somewhere else, probably in the next street over and was trying to get there.

Ranjan Posted at 6-4 06:39
Before the flight took off it gave you IMU error, were you aware what problem it can land the drone into?

The Mini 3 IMU (Inertial Measurement Unit) is a built-in device responsible for keeping the Mini 3 level and stable in the air, by monitoring the drone’s velocity angle, force, and attitude.

I was not aware of it. I ignored it intentionally, sometimes I flew with this error as well but the conditions are diff with a good view of the sky without buildings around. Nonetheless, I need to be careful with errors and do preflight tests before the actual flight.
Thanks for the response

Bashy Posted at 6-4 18:18
The low light may not help, as the bottom vision sensors need good light to work effectively and would need to rely on the much lower preciseness of the GPS to hold a position, that coupled with buildings hiding a  good view of the sky would have lowered the number of sats viewable from the drone's position, all in all, i think that the drone believed that it was somewhere else, probably in the next street over and was trying to get there.

I agree, maybe I overestimated drone capabilities   I need to be careful with the errors showed

The same exact thing happened to me today.  I was on my hotel balcony and wanted to get a good night shot of this hotel.  Every single time, my mini2 refused to fly at night, telling me to calibrate a compass that never calibrates no matter what I do.  This was the one time I got it to fly.  I figured I wasn’t going far so I could see it and it’d be safe.  Within 1 min of taking off, it started going sideways to the left.  I panicked and corrected but it kept going left.  At which point it hit the balcony and fell 60 feet.  Thankfully, a tree cushioned its fall and the only thing damaged were the rear right props.

I’m never flying at night again.  These drones won’t work at all at night.  I have no idea how people get such amazing YouTube videos at night.

djiuser_1rdg0OtKm2sc Posted at 12-24 08:07
The same exact thing happened to me today.  I was on my hotel balcony and wanted to get a good night shot of this hotel.  Every single time, my mini2 refused to fly at night, telling me to calibrate a compass that never calibrates no matter what I do.  This was the one time I got it to fly.  I figured I wasn’t going far so I could see it and it’d be safe.  Within 1 min of taking off, it started going sideways to the left.  I panicked and corrected but it kept going left.  At which point it hit the balcony and fell 60 feet.  Thankfully, a tree cushioned its fall and the only thing damaged were the rear right props.

I’m never flying at night again.  These drones won’t work at all at night.  I have no idea how people get such amazing YouTube videos at night.

Hi there. We suggest not using the aircraft in a poorly lit environment without GPS signals. The aircraft may drift when flying or may not hover when flying in these environments. Have a great day.

djiuser_1rdg0OtKm2sc Posted at 12-24 08:07
The same exact thing happened to me today.  I was on my hotel balcony and wanted to get a good night shot of this hotel.  Every single time, my mini2 refused to fly at night, telling me to calibrate a compass that never calibrates no matter what I do.  This was the one time I got it to fly.  I figured I wasn’t going far so I could see it and it’d be safe.  Within 1 min of taking off, it started going sideways to the left.  I panicked and corrected but it kept going left.  At which point it hit the balcony and fell 60 feet.  Thankfully, a tree cushioned its fall and the only thing damaged were the rear right props.

I’m never flying at night again.  These drones won’t work at all at night.  I have no idea how people get such amazing YouTube videos at night.

I fly at night quite often but before doing that one needs to understand the basics of how sensor work & how GPS lock works in the dark.

1. Sensors even if enabled will not be able to see obstacles in dark (so be aware)
2. VPS sensor can still sense in some cases as it has infrared beam for reading but then a lot depends if the surface is able to reflect it or not.
3. GPS lock above 12-15 satellites is minimum before you take off at night else drifting can happen which you need to manually control.

Most drifting happens when GPS signal are not locked & you are flying low (below 4 meters) for which VPS sensor needs enough light to lock its position.

Mini 4 pro & Air 3 have bottom additional light just to solve this drifting problem.

Here is simple hover test I did in dark for testing its stability at 1.2m height with 22 satellites locked.