Mini not stable when hovering

[slup]

Correct. There is an altitude limit for the VPS. The OP was flying under that limit apparently, therefore VPS is active. A data file would confirm that.

I saw that but your interpretation is incorrect. If you read that it say "When GPS is Unavailable" This means that the aircraft only uses the vision system for positioning. VPS is always active, unless you disable it....

when you fly outside and you get the home point message and take off the GPS and vision sensors are both working but as you fly higher then it is only GPS that keeps the drone on station, if you fly close to the ground then the vision sensors and GPS work together to keep the drone on station the only time the drone relies solely on the vision sensors is if GPS is not available,and then only to a height of 18ft

I would have echoed exactly the same as you two ... but that was before I read "When GPS is unavailable, the Downward Vision System is enabled ..."
What made me wonder was that it nowhere (perhaps I miss it though) is written that they work together at the same time ... if the altitude is low enough for VPS.

A read out from a log would be perfect ... that should make everything crystal clear.

 

[old man mavic]

i can assure you that the downwards sensors are working even if GPS is available ,how do you think the drone knows where the ground is ,when you are landing ,if you have noticed it does not just come straight down ,it hovers and waits for you to put full down stick to make it land ,you need to have enough light below the drone for it to see the surface

 

[Fly Dawg]

I would have echoed exactly the same as you two ... but that was before I read "When GPS is unavailable, the Downward Vision System is enabled ..."

The wording might be a little misleading, I agree. But that is typical for DJI manuals. Personally, I don't use the VPS. I prefer to control landings myself.

 

[DanMan32]

The wording might be a little misleading, I agree. But that is typical for DJI manuals. Personally, I don't use the VPS. I prefer to control landings myself.

VPS is for horizontal stability. What you're describing is RTH. And since on the Mini, VPS can't be turned off, it is used for landing to granularly detect distance to ground.

 

[DanMan32]

Deviation of a few CM is perfectly normal. Just look for YT videos of hovers of DJI models shown sped up and you'll see the deviation. You'll mostly find them for comparing flight times.

You might improve it some if you do an IMU calibration. Just be sure the AC is perfectly still for each phase of the calibration.
Prop condition will also affect stability. Brand new props will not have as much turbulence as ones that have minor blemishes.
Arm alignment may also factor in, considering they are foldable and stops can wear a bit.
But your stability is still very much in specs.

 

[Fly Dawg]

VPS is for horizontal stability. What you're describing is RTH.

No it is not. RTH is a completely different entity. I don't see where you get that from. RTH has nothing to do with VPS, depending on altitude. VPS and the barometer is used when GPS is not available. Can you clarify that statement?

 

[slup]

The wording might be a little misleading, I agree. But that is typical for DJI manuals. Personally, I don't use the VPS. I prefer to control landings myself.

Yeah ... you may be right. Strange how DJI describe the VPS so differently between the Mini & Air... not equal fuzzy in the Air manual.

 

[LaaLaa]

Hi

Original post says "I was flying it in a big interference zone" so maybe this is the answer. I guess the check is to fly somewhere safer?

 

[slup]

Hi

Original post says "I was flying it in a big interference zone" so maybe this is the answer. I guess the check is to fly somewhere safer?

Yeah maybe ... but still he claims a hoover accuracy within vision positioning spec ...



... and compere this occasion to other flights indoor & outdoor. We don't know anything about how the wind situation was (gusts?) & how proper the ground pattern was for locking in the VPS sensors.

Think the expectations are set to high in this case ...

 

[hiflyer201]

What is the ground like directly under the drone? If there are no features for the VPS downward sensor to see (eg smooth snow, sand, concrete) then the drone has to rely on just GPS for positioning and this means its position holding will be a lot looser. Stuff blowing around on the ground like leaves could also confuse the VPS a bit. I've "walked" a drone round my living room by just holding a patterned piece of paper under it and the VPS locked onto that.

interesting!

 

[theundertaker180]

I'm a brand new Mavic Mini drone operator and I was having this issue after updating to the newest firmware. I was testing it indoors before upgrading and it hovered beautifully, then I updated the firmware and it was giving me not stable hovering issues, even making me crash into the wall three times. I asked for help on this forum but to no avail until I looked into a factory reset using DJI Assistant. After opening DJI Assistant, I downgraded to the original firmware that was on the Mavic Mini when I opened the box and it is now flying as good as new. I think the firmware update is the problem because it was happening with me until I downgraded back to the original firmware. Do this using DJI Assistant. Post back with your results.

 

[Deleted member 109934]

After 8 flights my Mini is not stable anymore when hovering. I was flying it in a big interference zone and i noticed that is not stable in hover, it have a little side to side balance so i land it. Then i take off again and i keep it in front of me at 2m high to observe it. And it went slowly up and down and on sides, not much, some centimeters.The outside temperature was more than 10C. I did the IMU and compass calibrations, i tried after, the same. I changed the place, i have recalibrate, nothing, i went indoor, recalibrate, nothing, Can you please help me?

I have noticed very similar behavior, when brand new, my MM was rock solid (considering you follow all post above to the T, no wind, proper pattern underneath, lock GPS etc), then I nicked rear prop with my fingernail and it started to move not much but enough to notice it, I replaced the prop and it is solid again. Nick was almost invisible, you could only feel it when touching it with the fingernail. Then I polished it with 400 grit sandpaper and it was as new and replaced it back. MM was still solid.


here is how propellers looked:

 

[netsonic]

After opening DJI Assistant, I downgraded to the original firmware that was on the Mavic Mini when I opened the box and it is now flying as good as new. I think the firmware update is the problem because it was happening with me until I downgraded back to the original firmware. Do this using DJI Assistant. Post back with your results.

The previous firmware might help you with hoovering but it does not contain the fixes introduced in the current one like:

• Increased flight stability in some scenarios.
• Optimized propulsion system status prompts.
• Optimized performance when taking off in areas of high elevation.
• Optimized aircraft orientation control.
• Optimized gimbal control.
• Fixed issue: some remote controller model numbers were displayed incorrectly.

There were high altitude crashes, insufficient power, gimbal movement and other stuff that folks encountered when the old firmware was installed. Read the forum.
What do you think? Do these severe problems outweigh by far the risks of not having the mini hoovering properly?

 

[milovan]

Yeah maybe ... but still he claims a hoover accuracy within vision positioning spec ...

View attachment 88358

... and compere this occasion to other flights indoor & outdoor. We don't know anything about how the wind situation was (gusts?) & how proper the ground pattern was for locking in the VPS sensors.

Think the expectations are set to high in this case ...

off topic: how’d you do this type of screenshot? the torn paper thingy.

 

[slup]

off topic: how’d you do this type of screenshot? the torn paper thingy.

A PC program called Techsmith Snagit

 

[milovan]

A PC program called Techsmith Snagit

thanks!!

 

[nick neville]

YOU have left out one main compont, the sticks, I had one do the same thing and it was that the sticks were not calb. we had two drones that did the thing,when we would calb. the sticks and cut it off for the night, then the next morn. the calb. would be as much 12per sent. off. we contacted dji and they replaced both tx.

 

[locutus40]

After 8 flights my Mini is not stable anymore when hovering. I was flying it in a big interference zone and i noticed that is not stable in hover, it have a little side to side balance so i land it. Then i take off again and i keep it in front of me at 2m high to observe it. And it went slowly up and down and on sides, not much, some centimeters.The outside temperature was more than 10C. I did the IMU and compass calibrations, i tried after, the same. I changed the place, i have recalibrate, nothing, i went indoor, recalibrate, nothing, Can you please help me?

do a imu calibration.. mine does the same thing wobbles alittle no wind side to side see dji has always had imu errors the phantoms always had it the mavic pro etc so do a calibration and see if that helps mine if i restart it it goes away and is rock solid also land slow avoid fast flying etc

 

[DanMan32]

No it is not. RTH is a completely different entity. I don't see where you get that from. RTH has nothing to do with VPS, depending on altitude. VPS and the barometer is used when GPS is not available. Can you clarify that statement?

That's what I said. RTH and VPS are separate and the one I commented against confused the two at least in terms. The only case the downward camera is used in RTH is for landing protection.

Anyhow, how do you not use VPS, and what has that got to do with landing? Turning off VPS is not yet an option on the Mini, and if you lose GPS, you'll want VPS anyway to keep your horizontal movement stable, otherwise you have ATTI. That's what I was getting at.

 

[Fly Dawg]

Anyhow, how do you not use VPS, and what has that got to do with landing?

This isn't specifically for the mini....Over the years, I have found VPS is, iffy at best. Allthough the new algorithms may improve performance. I find that I can land the aircraft much smoother manually than depending on VPS, for low altitude adjustments.