I wanted to take a flight inside of a building with a 13 story opening.  I had clearance to fly and the building only had a few people in it.

I did not expect to get GPS, as I was indoors.  I expected to be able to fly in opti mode.  The aircraft went into attitude mode, and was drifting uncontrollably.  I was able to block it from going over the balcony (second floor) and was able to catch it and force land it.  I looked at the log (found here) and see that it was in P-GPS with no sattelittes and then went into Atti mode.  Is there a way to force it into Opti mode so that i can fly indoors with the stability that an enclosed environment offers?

Whoa.. Got a question... Does the Air also have TRIPOD Mode?  Would that have helped any?

STRIDE8 Posted at 2018-7-12 08:07
Whoa.. Got a question... Does the Air also have TRIPOD Mode?  Would that have helped any?

Yes, it has tripod mode.  I'm not sure if it would have helped.  I'm open to suggestions, because I would really like to take a few shots from inside this building.

Put the prop guards on, ensure sufficient light for the VPS to sense the ground, don't go too high and make sure the sensors are clean before take off. I always use tripod mode on the rare occasions I fly indoors - and don't forget to set failsafe to hover so if you lose signal the drone won't suddenly shoot up 20m+ to RTH...

prop guards are on.  I didn't set the RTH, but it couldnt' set a home point anyway with no GPS.    I am still not skilled in flying in atti, so I could not control it.  there was one point where i was full stick down  and it wasn't paying my input any attention

Set to hover mate as even without a RTH set if you do lose signal it will still climb in altitude if signal is lost unless you preset the command for it to hover or land and not RTH. That’s why the options are listed in the app.

I would also turn off landing protection

3-D Posted at 2018-7-12 09:37
prop guards are on.  I didn't set the RTH, but it couldnt' set a home point anyway with no GPS.    I am still not skilled in flying in atti, so I could not control it.  there was one point where i was full stick down  and it wasn't paying my input any attention

You need one of these  GPS repeater kit for L1 signals
Bet kit isn't cheap.

A CW Posted at 2018-7-12 09:40
I would also turn off landing protection

I'll do both of these Andy.  didn't even think of changing RTH altitude while inside.  That could have been ugly.

HedgeTrimmer Posted at 2018-7-12 11:13
You need one of these  GPS repeater kit for L1 signals
Bet kit isn't cheap.

yeah, i'll bet it's not cheap.
and i'll also bet i couldn't get it here by this week!

3-D Posted at 2018-7-12 12:23
I'll do both of these Andy.  didn't even think of changing RTH altitude while inside.  That could have been ugly.

No worries mate - just remember how the drone reacts in all potential worse case scenarios - easier said than done.

3-D Posted at 2018-7-12 12:28
yeah, i'll bet it's not cheap.
and i'll also bet i couldn't get it here by this week!

This is the one I use for those rare occasions I need to fly indoors, I just plug the USB A side of the cable into a regular wall phone charger. Works Great. Run the receiver to the outside and transmitter on the inside.

GPS Repeater

Settings. If your not going to be more than 20 m from drone, set RTH to land
Signal set to hover.
In order to obtain opti mode you need good lighting and good textured flooring opti needs good patterns to lock on to.
It won’t make any difference if your craft goes between opti and gps, in fact it will be more stable.
Atti mode will only occur when you lose opti mode.
Tripod mode is probably the safest mode to fly indoors.

hallmark007 Posted at 2018-7-12 14:59
Settings. If your not going to be more than 20 m from drone, set RTH to land
Signal set to hover.
In order to obtain opti mode you need good lighting and good textured flooring opti needs good patterns to lock on to.

I can't set RTH to land in this instance because I could not guarantee that it would be able to land someplace I could get to.   I'll have to set it to hover and hope i can regain connectivity before the battery dies.

3-D Posted at 2018-7-12 15:16
I can't set RTH to land in this instance because I could not guarantee that it would be able to land someplace I could get to.   I'll have to set it to hover and hope i can regain connectivity before the battery dies.

You cannot set RTH to hover, only loss of radio signal can be set to hover, remember to always change back loss of signal to RTH when you fly outdoors, reason I said set RTH to land within 20m, if you reach RTH battery level you will need to land, other option is not worth thinking about.

Your craft may also be going into Atti mode because of taken off with weak gps, you should wait before taking off for either opti mode or gps with better signal.

hallmark007 Posted at 2018-7-12 15:35
You cannot set RTH to hover, only loss of radio signal can be set to hover, remember to always change back loss of signal to RTH when you fly outdoors, reason I said set RTH to land within 20m, if you reach RTH battery level you will need to land, other option is not worth thinking about.

Your craft may also be going into Atti mode because of taken off with weak gps, you should wait before taking off for either opti mode or gps with better signal.

right.  I was thinking of signal loss.    but i probably won't be able to fly in the building again this week.  For the rest of the week there are events happening in the evening, and i'm not getting up at 4 am to go in to take photos.  It's not that serious!

Turn off all sensors.  Seriously do you have a cheap non gps drone you can practice with?  This is a really good way to learn to fly without relying on gps and being able to react fast and have complete control.  This is what I did before even getting my MP and telling you it really does help.  I have a few cheap small drones I practice with in the house and a MJX Bugs 2 that I can turn off gps outside and practice.  Hope you do not take this the wrong way just trying to help.  Last thing I want is you to crash your new MA my friend.

Is the building inside light enough for opti? Is the floor has enough pattern for the sensor to work? You may try on light area with pattern on floor to see how it works. Check is any wind in the building.

SparksBird Posted at 2018-7-12 17:08
Turn off all sensors.  Seriously do you have a cheap non gps drone you can practice with?  This is a really good way to learn to fly without relying on gps and being able to react fast and have complete control.  This is what I did before even getting my MP and telling you it really does help.  I have a few cheap small drones I practice with in the house and a MJX Bugs 2 that I can turn off gps outside and practice.  Hope you do not take this the wrong way just trying to help.  Last thing I want is you to crash your new MA my friend.

Yeah, Bill B just sent me a nano qx.  I didn't have a lot of time to learn it before this trip.  I'm not going to do anything to risk the new MA.  I'll stick to outdoor flights, and I'm still trying to get those night shots.
When i attempted take off in that building, and it didn't do right, i was in a very safe place, and was not in danger of losing it.  I wanted to test it there, before i tested it here:



I have learned a lot, and the best thing that I've learned is that I don't know isht.

Thanks for the advice.

GDL Posted at 2018-7-12 17:46
Is the building inside light enough for opti? Is the floor has enough pattern for the sensor to work? You may try on light area with pattern on floor to see how it works. Check is any wind in the building.

See the picture above.  I took that from the 14th floor.   I think there is enough pattern on the ground floor to work with, but today when i took that picture, it had been covered. and was full of people.

3-D Posted at 2018-7-12 17:51
Yeah, Bill B just sent me a nano qx.  I didn't have a lot of time to learn it before this trip.  I'm not going to do anything to risk the new MA.  I'll stick to outdoor flights, and I'm still trying to get those night shots.
When i attempted take off in that building, and it didn't do right, i was in a very safe place, and was not in danger of losing it.  I wanted to test it there, before i tested it here:

Hey we are all still learning and have to start somewhere.  I am still far from what I consider a pro by any means.  I still like to practice with my smaller quads because lets face it the DJI quads really do not teach us how to fly they pretty much fly themselves.  That building is very cool futuristic looking.  

The GPS repeater is going to cause more trouble!

If you think about what it is doing - It is receiving the signals and re-transmitting them. But the GPS uses the timing of the signals to determine it's location. So it isn't possible to use this so it can pinpoint it's location accurately within the building. So the drone may thing it's in GPS mode but as the location isn't accurate it will drift just like in atti-mode. It may even be worse as it is confused by false location info. For example if it is drifting but thinks it's the stationary then that will confuse the algorithms that keep it stable / stationary.

GPS repeaters are commonly used for 3 scenarios...
It allows emergency vehicles to lock onto satellites when on standby in a covered area.  This speeds up locking onto a signal when they exit the covered area in a time critical emergency.
It allows equipment that relies on GPS time signals to work inside.
It allows testing of GPS equipment inside.

If it worked as expected I would imagine they would add repeaters into shopping centres, etc. Then they could provide maps, offers, etc. They don't because it doesn't work.

SparksBird Posted at 2018-7-12 17:56
Hey we are all still learning and have to start somewhere.  I am still far from what I consider a pro by any means.  I still like to practice with my smaller quads because lets face it the DJI quads really do not teach us how to fly they pretty much fly themselves.  That building is very cool futuristic looking.

i'll have to take a better picture of the inside of the building.  It is not wavy.  That picture is a panorama taken with my phone.    This is another one, that more closely shows how the building interior is.  It's just that the panorama didn't turn out as good as I would have liked.

My first launch was from the 2nd floor where there is plenty of space to go directly up and not run into any other floors.

That place looks ok for vision mode. Not sure why it won’t work. MA not only use the downward sensor to position but also can use front and back sensor to provide more accurate position in house. They even say the vision sensor can used to fix heading without compass. I am surprise that it’s not working in that large building. Is the space there too big and vision only works for short distance?

I'm not sure what really happened.  I'm still a little jumpy, and until I learn to have complete control if it goes into Atti mode.  I didn't even give it a second chance.  

The floor will be clear tomorrow, so I may try again.  I'll be in a clearer space to take off.  We'll see what happens.