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Mavic 2 Pro fly without GPS suggestions

Dronenewbie8

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Hello. I need to fly my M2P inside of a large open warehouse with no GPS. I've never done this before and not sure what to expect. Will I still be able to accurately control the drone or will it start squirting around unpredictably? Any help / suggestions would be appreciated! (I do have prop guards). Many thanks
 
There have been many MANY discussions on this topic. You will not have position lock so the bird will drift. If you are familiar with inertia then that is what will happen. You literally will have to fly it manually (compensating for the drifting). You can read some of these suggestions: "Flying Indoors" . . . good luck ;)Thumbswayup!
 
There a are a couple methods, My Favorite is to gain GPS lock first and than fly the Drone into the Warehouse keeping watch on the GPS signal. This is different than trying to gain signal inside and than flying inside which is much more difficult .

Phantomrain.org
Gear to fly in the Rain.
 
There a are a couple methods, My Favorite is to gain GPS lock first and than fly the Drone into the Warehouse keeping watch on the GPS signal. This is different than trying to gain signal inside and than flying inside which is much more difficult .
If the warehouse building blocks GPS signal, it won't help a bit to get GPS outside and then fly into a GPS-denied environment.
 
Hello. I need to fly my M2P inside of a large open warehouse with no GPS. I've never done this before and not sure what to expect. Will I still be able to accurately control the drone or will it start squirting around unpredictably? Any help / suggestions would be appreciated! (I do have prop guards). Many thanks
If the building blocks GPS signals, you could still have horizontal position holding with the VPS sensors.
But that would depend on having suitable lighting and the floor having a recognisable pattern or texture.

If the drone has no horizontal position holding, it would still be controllable and won't start squirting around unpredictably.
But the handling will feel quite different because the drone won't have any "brakes" and will keep coasting when you go hands-off with the joysticks (a bit like driving on ice).
You would need to be very gentle on the sticks, and with practice you could get the hang of using gentle reverse thrust to slow the drone.
But if you go hard on the sticks things won't go well.
 
Any help / suggestions would be appreciated! (I do have prop guards). Many thanks
Something I should have added ...
There will be height restrictions if you fly without GPS.
According to the manual (p. 57)
Height is restricted to 16 ft (5 m) when the GPS signal is weak and DownwardVision System is activated.
Height is restricted to 98 ft (30 m) when the GPS signal is weak and Downward Vision System is inactivated.

With VPS to provide position holding (if the lighting and floor is suitable), you can only fly to 5 metres higher than launch point.
If you disable VPS sensors in your app settings, you can fly to 30 metres.
 
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Meta4 . . . you help everyone at any level. One day I'll amass a micron of the knowledge you have. I hope I can be as helpful (someday).
 
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The way DJI stores get over this problem is to have markers on the floor to help the drone differentiate between one part of the floor and another. I have overcome this problem several times by scattering a number (10 to 20) old CD cases around the area I will be flying indoors, within about a metre or so of each other. It worked. I had no GPS signal and no drift. The VPS was limited to 5 metres height but that was enough for the clients needs.
 
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You just have to learn to fly the drone instead of letting the various sensors fly it for you. Likes oldies had to when flying an old RC Helicopter.
 
Also be aware that the upward looking obstacle sensors may cause you problems, i.e. limit height. Indoors (house with maybe an 8ft ceiling ) 'mine' seem to want to keep the drone 3-4ft from the ceiling and they can even force the drones to descend e.g. if the drone passes under a ceiling light etc.
I think you can switch them off by switching to sports mode but that might be a bit risky.
 
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Even without no GPS or VPS, you still always have full control in ATTI mode by moving the control sticks. It's only if you let go of the sticks, sticks centred, where you'll notice an obvious difference. The drone cannot automatically brake to a halt and hold position when it has no means to determine its actual position.

So, if you're flying forward and release the sticks to centre, the drone will still level itself and maintain altitude, but it will continue drifting forward unless you input some reverse stick to force it to stop. Or if there's any wind, including that generated by its own propwash in a confined space, that will push the drone around. You just need to actively use control inputs to move and hold the drone where you want it.

On my Phantom-1 and Phantom-3, I can manually select ATTI mode whenever I want. I made a video long ago showing the difference in flight behaviour between GPS vs ATTI modes. At the time, people were experiencing lots of fly-aways with their original Phantoms. There was a theory that a GPS glitch could somehow cause the Phantom suddenly to believe it's supposed to be in China and it would flyaway uncontrollably. The intent of this video was to debunk that myth, but it does show the difference between GPS and ATTI modes.

 
would tripod mode or beginner mode work with no GPS, and would that be worthwhile or helpful??
Otherwise, would adjusting the EXP curves to slow down the stick response be helpful?
Prop guards definitely. Longer sticks also make stick movement less jerky.
 
Good advice from Crouching Leopard. With no GPS the only help the drone gets to maintain height/position are the bottom sensors. If there is a floor with clear patterns on it, carpets etc, you should be OK otherwise, as CL says make the floor contrasty by scattering things over it where you're going to fly.
 
With no GPS the only help the drone gets to maintain height/position are the bottom sensors.
No GPS has no effect on vertical position holding, only horizontal.
The drone will maintain height just the same as it does with GPS, because GPS does not control height at all.
 
Good advice from Crouching Leopard. With no GPS the only help the drone gets to maintain height/position are the bottom sensors. If there is a floor with clear patterns on it, carpets etc, you should be OK otherwise, as CL says make the floor contrasty by scattering things over it where you're going to fly.
Agreed. Single colour carpets and other single colour floor surfaces need some contrast adding, that's why I find cd / dvd cases so useful. Cheap, easy to carry and light.
 
No GPS has no effect on vertical position holding, only horizontal.
The drone will maintain height just the same as it does with GPS, because GPS does not control height at all.
Sorry, I don't think that is true Meta4. The bottom sensors control height (mainly for landing) and horizontal (with a suitable contrast surface) between 0.5m - 10m altitude. Above that I think I am right in saying that the built in barometer and GPS controls the height and GPS the horizontal position. With weak or no GPS you are flying ATTI (manual) same as we do with RC planes and helicopters, with a little help from the barometer on height but no horizontal help.
 
Sorry, I don't think that is true Meta4. The bottom sensors control height (mainly for landing) and horizontal (with a suitable contrast surface) between 0.5m - 10m altitude.
Your drone has two different downward facing sensors.
The one that measures height does not require pattern or texture.
Above that I think I am right in saying that the built in barometer and GPS controls the height
GPS has nothing to do with height.
Height comes from the barometric sensor.
Flying in Atti Mode, your drone will maintain height with or without VPS.
 
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