So I've been flying the Phantom 3 Pro for a while now and it typically does an amazing job outdoors.  My indoor flights have been anything but successful.  

Essentially I leave the thing in P mode as I understand that to be the "smart" way to go.  My assumption is an issue with GPS signal, more or less "almost enough" and then "just enough" signal.  I'll take off, it'll go to hover about 4 feet then start drifting, or I'll be moving up or down and it'll magically make a big adjustment.  Again my guess is this is based on getting/losing GPS and reacting to it, well when you're in a 15x15 room a movement of 3 feet is a big deal.

Additionally it seems that indoors my app/remote is constantly jumping to ATTI mode, then back, then back to ATTI etc.  What causes this??

I was under the impression that the VPS would keep me safe indoors, I'm not expecting perfection but lets just say I'm not comfortable flying this thing around inside at all, it literally isn't predictable in its current state.

Maybe something I'm not thinking of is causing the switch to ATTI?  Should I somehow disable GPS when flying in an area it will likely cut in and out?  I'd love suggestions because this is certainly an important aspect to me.

I actually just went to test it again and noticed "enable vision position system" was turned off in the app, why I have no idea.  I enabled it and it seemed to act better, however again it would jump to ATTI mode, seemingly quite randomly.  I was in the middle of flying so it was hard to pay attention to what switch it was making but you would hear the app say "ATTI mode" many times.

Ideas???

So far from what I've heard, the VPS works well in multi-textured environments, maybe your floor is a-tonal?

carlcronejr@yah Posted at 2015-5-27 08:32
So far from what I've heard, the VPS works well in multi-textured environments, maybe your floor is  ...

Numerous environments, non tonal floors, it has to be something more

Well, it sure does not work well with VPS turned off - always make sure its active when out of range or sight of GPS.  Mine's dead stable in the house - wooden floors.

I tried it indoors and found on a multi textured pattern, PH3 stayed pretty well stationary, went into the next room with thick 1inch lines running length wise (spacing of lines 10 inches) and the PH3 drifted any direction up to a meter, would not stay still.

I'm having the same problem.

The first thing is to understand that GPS reception is mostly useless indoors. Many buildings have metal roofs which will almost completely block GPS reception. So fly in ATTI mode with VPS switched on. As long as the ground surface has a strong pattern to it, the VPS system should be able to see it and lock to it. But it is also very dependant on lighting. A poor lit ground or floor surface will not work. The camera in the VPS system is not very good, and needs plenty of light and a strong surface pattern to work properly. Even so, it is not wise to undertake clever stunt flying indoors and you must be well practised flying in ATTI mode if you expect your aircraft to survive.

Exactly .... switch off from GPS mode and let AC follow the VPS and your control input.

Note that uneven non-solid surfaces such as long grass / water / 'domestic debris' inside on floors - all will play havoc with VPS.
OK how does it work ?

It has 2 forms ..... the 2 large circles are ULTRASONIC sensors that gauge height from a solid ground / floor .... accuracy is about 0.1m, viable to about 3m verticallyand third small hole is the grey-scale camera.

VPS (Vision Position System)



VPS includes two ultrasonic sensors (red) and one optical flow sensor (green, probably a grey scale cam) , mounted including its electronics onto the bottom of the Phantom 3 shell. These sensors, operating from 0,3 up to 3m help to stabilize the Phantom 3 hover indoors, where no GPS is available, also working outdoors as well at available light (>100lux) and contrast. This is greatly stabilizing low level flights.

But keep in mind, VPS systems don´t work reliable above water, so better turn it off, if thats the idea.
Nigel

Just another comment on your indoor flying. Follow what has already been suggested by others, but in addition I would like to add one suggestion. Make sure when indoors that you don't have your RTH set to return home. In the chance you lose signal you don't want your aircraft shooting up thru the ceiling trying to come home. Turn it to Hover. Thought this might be worth mentioning.

RicardoGray Posted at 2017-10-4 07:31
Just another comment on your indoor flying. Follow what has already been suggested by others, but in addition I would like to add one suggestion. Make sure when indoors that you don't have your RTH set to return home. In the chance you lose signal you don't want your aircraft shooting up thru the ceiling trying to come home. Turn it to Hover. Thought this might be worth mentioning.

First thought that comes to mind ... RTH depends on having a GPS recorded Home Position ... and at point of activation of lost signal - a GPS location then to know how to get home ...

So my question will be - how can RTH even start to work if indoors .... and GPS mode switched of ?

Interesting item ... will have to investigate this one ...

Nigel

solentlife Posted at 2017-10-4 09:29
First thought that comes to mind ... RTH depends on having a GPS recorded Home Position ... and at point of activation of lost signal - a GPS location then to know how to get home ...

So my question will be - how can RTH even start to work if indoors .... and GPS mode switched of ?

nigel would rth still work in att mode?

solentlife Posted at 2017-10-4 09:29
First thought that comes to mind ... RTH depends on having a GPS recorded Home Position ... and at point of activation of lost signal - a GPS location then to know how to get home ...

So my question will be - how can RTH even start to work if indoors .... and GPS mode switched of ?

Ah, you have a good point. I guess I had an experience where I was inside of a large building, not exactly in my house if you will, and it was a metal one. The aircraft did capture a couple satellites when I move close to the overhead doors, and then would drop out as I moved around inside. I was flying in ATTI mode though. I guess maybe I was more thinking about "loss of signal"  and not RTH. But I agree with RTH you need to have GPS, but would the signal loss automatically try trigger a RTH or just do nothing? I realize the lost signal is highly unlikely, but just thinking out of the box.
Edit: Trying to remember my filming in the large building I was referring to. After thinking about it (it was a couple years ago and haven't done it since), but I remember taking off outside and then flying in thru the larger overhead doors. Which it would have established a home point I'm sure. I remember I turned the RTH action to just hover thinking of the situation I described, but now I wonder if I had lost signal what could have happened??? I'm guessing now thinking more about it, the logical answer might be that if no GPS is available, the aircraft would just hover until it regained the signal right? And if flying in ATTI mode anyway, probably would not initiate a RTH. Over thinking this!

repairman Posted at 2017-10-4 11:16
nigel would rth still work in att mode?

Page 11 of manual .... Flight Mode.

Page 14 of manual .... Failsafe RTH

Its not absolutely clear if RTH fails but it does say that if GPS signal is weak AC cannot return to Home Point.

One of the points to be aware of - GPS signal can be received inside buildings ... many yachts / cars / RV's are proof of this where Rx's sit inside ... also it is not unusual to sit at a desk ... switch on a GPS Rx and by just moving about you will find active spots even when not at a window etc.

So that tells us we should de-activate GPS or any action that relies on it just in case it may pick up a signal.

Nigel

solentlife Posted at 2017-10-4 22:30
Page 11 of manual .... Flight Mode.

Page 14 of manual .... Failsafe RTH

I think you are spot on as usual Nigel. Best practice would be turn it off, to avoid any funky stuff happening.

RicardoGray Posted at 2017-10-5 04:08
I think you are spot on as usual Nigel. Best practice would be turn it off, to avoid and funky stuff happening.

Be careful .... you may upset the 'natives' !!

Cheers - many thanks.

Nigel