Return to home function

[JD1964]

OK first question for me the new guy. I understand the return to home feature. I understand if it goes into action the drone will ascend to the preset altitude before returning home. All good with that. However, I fly low level in my yard which has a canopy of trees with a few access holes to the sky.

If I'm flying at 3 feet above the ground and the drone battery gets too low and I don't land it in time, will the return to home feature cause the drone to ascend into the canopy cover and crash, or will it just set itself down wherever it happens to be hovering?

I don't anticipate a problem but I'm curious what might happen in this instance.

 

[FLDave]

Read the manual to get the details of how your drone reacts to RTH command under differing scenarios. The RTH feature is not the same for all models.

 

[Yorkshire_Pud]

I understand the return to home feature.

I doubt that.
I am another one saying read the manual.
The RTH behaviour varies from model to model and, model depending, all sorts of things can influence the behaviour, including distance from the home point and drone height.
If you don't know what it will do then you could cost yourself the drone.

At the very least you should say which drone you have.

The RTH behaviour of every model of DJI drone I have flown has caught me out at least once, I would also strongly suggest that you work though each and every RTH behaviour in experimentation in a safe, wide-open-place, with no trees or obstacles BEFORE you encounter those behaviours for real in a real flight.

Under a tree canopy the drone may not even RTH at all.
It can't if it does not have sufficient GPS to satisfactorily establish the weherabouts of the homepoint and itself and trees tend to reduce the GPS count.

If a modern DJI drone gets too low, 18" or thereabouts, and you are applying down stick it WILL land and you have very little time to do anything about it.

Given that there are flaws in virtually everything you have said I suggest you read the manual several times and then ask question about anything you even think you are unsure of.

I am not lecturing or slagging you off, I'd just rather not have your next thread starting "I crashed my drone, why or help?".

 

[JD1964]

I'll give the manual a look. It's a Mavic Mini

 

[JD1964]

I actually see 16-17 satellites connected when I'm in my back yard under and near the tree canopy. I assume this means that adequate communication is established.

 

[RodPad]

JD1964

mavicpilots.com

Sorry you already started I new thread, before I did the welcome thing, Anyways I knew you were using a MM1.

Welcome to the forum!
I recommend you add a signature, also you posted this in general.

Yes they are many sections
Mini 1

I takes a while, these members are awesome and they help!

Please stay on this thread, they now know what bird you got..

And I will be watching, there are many RTH variables.

Let say you just lost signal, you dropped the remote, its going to do the RTH procedure, it will go to the height setting and then head home. If its above that, it return at that level and then land.

Others, if I'm wrong then chime in

Rod ..

 

[Walleye Hunter]

Checking the manual is a good start and if you can, take it out to a clear field and try it under different circumstances. i e distance from home, altitude at short distance from home and of course, long distance from home. Do the same and shut the controller off and see what it does with loss of signal. BTW, you should have settings on what to do with loss of signal. Mine has hover, land and RTH. I can see no reason for anything other than RTH unless you're out on a boat. Then hover might be best. Mine is supposed to recognize overhead obstacles on a climb for RTH but I'm in no hurry to try that one out.

 

[GFields]

Moved thread from > General Discussion to > Mini 1

 

[JD1964]

take it out to a clear field and try it under different circumstances. i e distance from home, altitude at short distance from home and of course, long distance from home. Do the same and shut the controller off and see what it does with loss of signal. BTW, you should have settings on what to do with loss of signal.

Good idea

 

[hiflyer201]

read the manual and practice it a few times. based on distance from the home point it remains at the same altitude. There are many factors. loss of signal, low battery, low cell and it will land..etc.. Never launch on a highway or under a canopy of trees. I say that because you are probably not going to stay in your backyard forever. Make sure you check your RTH setting. I've made the mistake of leaving mine on settings that would have meant the loss the drone if it had disconnected.

 

[KB9Radio]

I would set your battery warning level at a point where you can easily fly home. Don't ignore the warning, when it goes off, get out from under the canopy and increase altitude to where you can easily fly it back to you and land. The drones are very good and quite reliable, but you still need to be careful and use some common sense

 

[Yorkshire_Pud]

I actually see 16-17 satellites connected when I'm in my back yard under and near the tree canopy. I assume this means that adequate communication is established.

Your lucky, where I often launch from I don't get good GPS until clear of the trees. This means I am limited to a height of 5m and have to fly horizontally until the drone can see the sky and get sufficient GPS. Then I can raise the drone above tree height, bring it back overhead and reset the home point.
Besides I think the minimum RTH height for the Mavic Mini is 15m which would almost certainly out the drone up into the canopy. If correct your best option would be to switch the failsafe/loss_of _connection option to hover and walk towards the drone. BUT NOTE if you do not reestablish connection a hover will end in a low battery RTH.*
Even if you set the failsafe to land the drone may still end up hovering since it can reject the landing site. I am pretty certain I have seen my Mavic Mini, or perhaps the Mini 2, reject a landing site even when at critical battery levels and think it didn't "force land" until the battery reached 0%.

*That raises an interesting question, what happens if the hover is within 20m of the home point.

 

[JD1964]

I tried the return to home for the first time in a big field this morning. That works as it should obviously.

I also did a depleted battery test. I had the drone hovering 4’ above the ground just a few feet away from me. I ignored the land now warning persistently and the drone eventually just landed itself in that spot.

My thought was I might find myself navigating at low level back in the woods over a steam bed and whatnot. I just wanted to understand what might happen in certain less than ideal situations. Being deeper in the woods means I may not always be able to avoid launching beneath a tree canopy. Therefore in that situation, I would not want the drone to ascend automatically for any reason.

In these cases I’m most likely to be in close enough proximity to the drone that the RTH including ascension will not happen (according to the manual). In the event of a low battery that was ignored too long, it will just land in place which is acceptable to me.

Loss of signal is the next concern. I see by further reading the manual I can control what happens in that scenario. If under s canopy as I describe, I think I’ll have the loss of signal command set to hover. That way I can move over and make sure a landing area beneath is best it can be. Or maybe even reach up and arrest the drone with my hand. Or better yet, wait a bit and see if the signal re-establishes itself.

If you have any relative thoughts on this, please share them.

 

[Meta4]

Therefore in that situation, I would not want the drone to ascend automatically for any reason.

In these cases I’m most likely to be in close enough proximity to the drone that the RTH including ascension will not happen (according to the manual). In the event of a low battery that was ignored too long, it will just land in place which is acceptable to me.

Perhaps you should read the manual more closely.
Your drone would only land in place if it is closer than 20 metres from the launch point.
If >20 metres, it's going upwards.

Flying under tree cover is just asking for trouble, particularly with a low battery level..
Many drones have been lost or damaged doing just that.

 

[JD1964]

Perhaps you should read the manual more closely.
Your drone would only land in place if it is closer than 20 metres from the launch point.
If >20 metres, it's going upwards.

Flying under tree cover is just asking for trouble, particularly with a low battery level..
Many drones have been lost or damaged doing just that.

Ok I see. I was thinking 20 meters from the controller. My mistake

 

[JD1964]

However, in the event of loss of signal, it should behave according to the setting I selected. Correct?

 

[JD1964]

Additionally, I can update home point while in flight, right? So as long as I my last update is less than 20 meters away, it should not go up automatically. Right?

 

[RodPad]

Meta4

mavicpilots.com

I realty have not used my MM1 much, and never have tried the P3A to use visual sensors. Tree Canopy to me means loosing satellite signals, then it will drift of coarse. Your statements are always correct, well If a understand them.

JD1964

mavicpilots.com

Tree canopy loosing GPS, I can walk 200' from my location and test that but trees are Phantom Magnets.

Rod ..

 

[dccraven]

I once lost a Mavic Mini 1 in a lake because I set my RTH attitude to allow me to land until a tree canopy. The only place I could launch/land on the bank of the lake was under a tree canopy, so I thought that I could maintain VLOS and, should I need to use the RTH, I would ensure that the drone had a clear path back to my location under the tree canopy. Later I got very interested in photographing a feature just beyond a bend in the shore and didn't realize that as I move closer to the feature my drone would be blocked from my signal. Suddenly it experienced loss of signal and initialed RTH at the tree canopy height, traveling in a straight line to its launch point which now happened to cross the bend in the shore that I had moved around. It struck a tree, lost control and fell into the lake in an area which I could not retrieve the drone. Lost the drone but learned my lesson - planning to RTH below the tree canopy takes careful consideration...you must consider the worst case scenario. Know your planned flight path and set your RTH height to clear the highest obstacle between your HP and your flight path.

 

[JD1964]

I once lost a Mavic Mini 1 in a lake because I set my RTH attitude to allow me to land until a tree canopy. The only place I could launch/land on the bank of the lake was under a tree canopy, so I thought that I could maintain VLOS and, should I need to use the RTH, I would ensure that the drone had a clear path back to my location under the tree canopy. Later I got very interested in photographing a feature just beyond a bend in the shore and didn't realize that as I move closer to the feature my drone would be blocked from my signal. Suddenly it experienced loss of signal and initialed RTH at the tree canopy height, traveling in a straight line to its launch point which now happened to cross the bend in the shore that I had moved around. It struck a tree, lost control and fell into the lake in an area which I could not retrieve the drone. Lost the drone but learned my lesson - planning to RTH below the tree canopy takes careful consideration...you must consider the worst case scenario. Know your planned flight path and set your RTH height to clear the highest obstacle between your HP and your flight path.

Thanks for sharing this as it gives others a chance to think about how it might be prevented.

Here’s an idea. If you will be flying away from your location over water, just go ahead and set your RTH altitude high enough to clear the taller trees. Then if the RTH initiates automatically or if you need to manually do it, watch the map as the drone crosses the lake towards you. When you see it visually or when you can verify by the map that it’s over the lake, then cancel the RTH and take over manually to bring it back to you under the canopy. This scenario assumes the drone and controller will re-establish communication as it returns in your direction.