Sensors or no sensors when flying over water

[crs06e]

I just purchased a new Mavic Air 2 to get footage of boating/fishing/jet skiing. Therefore, it will practically always be used over water. I purchased the phantomrain sea lander kit and the wet suit kit so I would not lose another one (lost Mavic mini a week ago in water). In the posts about the sea lander kit, I kept seeing people talking about NOT using the sensors when flying over water. Can someone explain the pros/cons of this?

 

[aokusman]

Just don’t fly low over water.

 

[crs06e]

Just don’t fly low over water.

Don't fly low over the water with sensors on or off?

 

[Phantomrain.org]

I just purchased a new Mavic Air 2 to get footage of boating/fishing/jet skiing. Therefore, it will practically always be used over water. I purchased the phantomrain sea lander kit and the wet suit kit so I would not lose another one (lost Mavic mini a week ago in water). In the posts about the sea lander kit, I kept seeing people talking about NOT using the sensors when flying over water. Can someone explain the pros/cons of this?

There our two types of flying on the water:

Flying over the water which means 25 ft or higher

Flying on top of the water which means 25 ft of lower and this is where Sensor can catch the reflection of the sun on thewater and get confused, that confusion can cause the drone to dip , or even land in the water.

The bigger problem is when your on a boat or pier and your bringing it back but the drone senses your environment poles , wires, mast, fishing poles people and it just freezes. your on low battery after the flight and panic set in and accidents happen.

The only reason why most people do not turn off the Sensors is remembering to turn them back on.

I have a video where I post the Phantom taking off of a pier and than just getting stuck as the sensors get confused had I flown over the pier i would not have been able to get my drone back..

Its a little rough but I think it shows the idea well enough. I am only able to move up or down as sensors get confused at times.

Looking to ship out monday by the way.


Here is that video. I just cannot get the Phantom to move forward once the sensor beeping starts.
This is an example of how sensors are not flawless.

Once I turned the sensors off I was good to go. Once you have a close call you will keep the sensors off if you flying on top of the water or taking off from an action spot .


Phantomrain.org
Gear to fly your mavic in the Rain or Float on Water.
Coal

 

[boblui]

I am assuming that you are referring to the bottom sensors, ie, the 3D camera and the IR sensor.

I have flown my M2P over water many times, no problem. The MA2 can only be better as it's newer. I myself always turn the bottom sensors on. The Pros and Cons of having them on are :

Pros
- no need to remember to turn them back on before landing. With them turned off, the drone will hit the ground hard when you pull the throttle stick all the way down to land the drone. I was stupid enough to try it out once and learned the lesson.
- the drone will be able to maintain altitude better as the downward sensors can tell the height above the water surface more accurately.

Cons
- the changing image of the water surface may make the drone believe that it's drifting in position or yawing. The flight controller will subsequently apply unnecessary correction. I have not seen such behaviour so far on my M2P. Even if the drone drifts, I would expect the magnitude to be minor as the IMU also plays a part in sensing the movement of the drone. I don't worry about this at all.

 

[crs06e]

There our two types of flying on the water:

Flying over the water which means 25 ft or higher

Flying on top of the water which means 25 ft of lower and this is where Sensor can catch the reflection of the sun on thewater and get confused, that confusion can cause the drone to dip , or even land in the water.

The bigger problem is when your on a boat or pier and your bringing it back but the drone senses your environment poles , wires, mast, fishing poles people and it just freezes. your on low battery after the flight and panic set in and accidents happen.

The only reason why most people do not turn off the Sensors is remembering to turn them back on.

I have a video where I post the Phantom taking off of a pier and than just getting stuck as the sensors get confused had I flown over the pier i would not have been able to get my drone back..

Its a little rough but I think it shows the idea well enough. I am only able to move up or down as sensors get confused at times.

Looking to ship out monday by the way.


Here is that video. I just cannot get the Phantom to move forward once the sensor beeping starts.
This is an example of how sensors are not flawless.

Once I turned the sensors off I was good to go. Once you have a close call you will keep the sensors off .


Phantomrain.org
Gear to fly your mavic in the Rain or Float on Water.
Coal

Great info! Thank you! I will be flying less than 25ft a lot so I will turn the sensors off. I definitely don't want to deal with those sensor problems. As far as turning them back on, do you turn them back on before you land once you are over your target such as the pier or the front deck of a boat?

 

[crs06e]

I am assuming that you are referring to the bottom sensors, ie, the 3D camera and the IR sensor.

I have flown my M2P over water many times, no problem. The MA2 can only be better as it's newer. I myself always turn the bottom sensors on. The Pros and Cons of having them on are :

Pros
- no need to remember to turn them back on before landing. With them turned off, the drone will hit the ground hard when you pull the throttle stick all the way down to land the drone. I was stupid enough to try it out once and learnt the lesson.

Cons
- the changing image of the water surface may make the drone believe that it's drifting in position or yawing. The flight controller will subsequently apply unnecessary correction. I have not seen such behaviour so far on my M2P Even if the drone drifts, I would expect the magnitude to be minor as the IMU also plays a part in sensing the movement of the drone. I don't worry about this at all.

I am new to this so I am not sure the exact sensors they were talking about. When you have them on, do you ever fly low to the water?

 

[Phantomrain.org]

I am new to this so I am not sure the exact sensors they were talking about. When you have them on, do you ever fly low to the water?

No there really is not need to : As others have mentioned the problem for many is forgetting to turn them back on . Once you master your memory skills you will be much better off.

 

[boblui]

I am new to this so I am not sure the exact sensors they were talking about. When you have them on, do you ever fly low to the water?

Yes, I did. I have tried hovering my M2P over water surface many times . If I apply down throttle stick, it will descend as usual until it is about 1 meter or so above the water surface and then it will pause there. The VPS reading on the DJI GO app will go red. At this point if I ignore the warning and keep the throttle stick down, it will land into the water but if I just pull the throttle stick down momentarily and then release, it will not move. Clearly it is able to detect how high it is above the water surface accurately. Not just that, it can tell that the surface is unsafe to land onto. If the sensors are off, it will just go straight down.

 

[Mavic Mac]

@Phantomrain.org - having never flown in the rain is it possible that the rain flowing/dripping off the drone causes problems with the sensors ?

 

[boblui]

This guy nearly lost his MP and Phantom by turning the bottom sensors off . so NEVER do that :

 

[Phantomrain.org]

@Phantomrain.org - having never flown in the rain is it possible that the rain flowing/dripping off the drone causes problems with the sensors ?

No I have had it happen on the boat a few times with the Mavic 2 , sometimes the sensors can work against you.
I have also had it happen while navigating thru paths thru trees , you get boxed in..

The Sensor cannot really pick up on the water drops as they see thru it.

 

[Phantomrain.org]

This guy nearly lost his MP and Phantom by turning the bottom sensors off . so NEVER do that :

I wrote to that guy, that is not how those sensors work , he had other issues which he confirmed latter on.
Its really a bad example , this was more like magnetic interference an compass error which he realized after the video was made.

Phantomrain.org
Gear to fly your AIr 2 in the Rain.
Coal

 

[boblui]

I wrote to that guy, that is not how those sensors work , he had other issues which he confirmed latter on.
Its really a bad example , this was more like magnetic interference an compass error which he realized after the video was made.

Phantomrain.org
Gear to fly your AIr 2 in the Rain.
Coal

Magnetic interference affects the compass. It canNOT cause the drone to go up and down. It can only cause the drone to drift horizontally in GPS mode.

 

[Phantomrain.org]

Magnetic interference affects the compass. It canNOT cause the drone to go up and down. It can only cause the drone to drift horizontally in GPS mode.

The drone drifted up and down more when the bottom sensors were off simply because it could only rely on the barometer to detect altitude and barometer is not very precise because it senses pressure change only. The bottom sensors are much more precise at close range so the drone was able to maintain altitude better.

When he went back to try again, he got completely different results with the test. However he did not pin point what was wrong the first time.
Either way it shows how sensors can be dramatic at times.

 

[volition]

how do you turn the VPS off on the MA2 or is it “all sensors off”.?
I also noticed if you go into sports mode it does have like a floor sensor (will only go so low) would that cause an issue over water?

who here has had the cohuna’s to fly 1m of the water in sports at good speed? Anyone?

 

[boblui]

how do you turn the VPS off on the MA2 or is it “all sensors off”.?
I also noticed if you go into sports mode it does have like a floor sensor (will only go so low) would that cause an issue over water?

I don't have the MA2 but have been told by multiple MA2 owners that VPS canNOT be turned off in any modes.
At that kind of height, the sensor is critical in maintaining the water surface clearance so it does not make sense to turn them off anyway.

who here has had the cohuna’s to fly 1m of the water in sports at good speed? Anyone?

The problem is not so much about the speed but the large tilting angle of the craft which may result in the reflected IR light not being able to go back to the sensor.

 

[Phantomrain.org]

how do you turn the VPS off on the MA2 or is it “all sensors off”.?
I also noticed if you go into sports mode it does have like a floor sensor (will only go so low) would that cause an issue over water?

who here has had the cohuna’s to fly 1m of the water in sports at good speed? Anyone?

We have tested the Air 2 in many ways, trying to get a forced landing on water,. We have also tested the Sport Mode an sensors over the water ,
We were not to able to get a forced landing to take place. We have quite a few videos on the water.

 

[volition]

We have tested the Air 2 in many ways, trying to get a forced landing on water,. We have also tested the Sport Mode an sensors over the water ,
We were not to able to get a forced landing to take place. We have quite a few videos on the water.

have you experienced any “odd behaviour” flying fast and lowish over water? Be it sensors on/off/sports mode?

For my mind, if I can zip around in an open field with confidence I cannot see how water should be much different (wave heights taken into account obviously). But not looking for any surprises when I give it a go.

 

[Quick_Star24]

There our two types of flying on the water:

Flying over the water which means 25 ft or higher

Flying on top of the water which means 25 ft of lower and this is where Sensor can catch the reflection of the sun on thewater and get confused, that confusion can cause the drone to dip , or even land in the water.

The bigger problem is when your on a boat or pier and your bringing it back but the drone senses your environment poles , wires, mast, fishing poles people and it just freezes. your on low battery after the flight and panic set in and accidents happen.

The only reason why most people do not turn off the Sensors is remembering to turn them back on.

I have a video where I post the Phantom taking off of a pier and than just getting stuck as the sensors get confused had I flown over the pier i would not have been able to get my drone back..

Its a little rough but I think it shows the idea well enough. I am only able to move up or down as sensors get confused at times.

Looking to ship out monday by the way.


Here is that video. I just cannot get the Phantom to move forward once the sensor beeping starts.
This is an example of how sensors are not flawless.

Once I turned the sensors off I was good to go. Once you have a close call you will keep the sensors off if you flying on top of the water or taking off from an action spot .


Phantomrain.org
Gear to fly your mavic in the Rain or Float on Water.
Coal

My problem here is the West Virginia Hills I live in and if I am on top of a hill and fly the drone out of my sight and down over the river I do not know if the height measuring system is giving me the height over the water or the height from where it took off on the hill. I want to fly between 5 and 10 feet over the water and under the bridges but if the drone is not in my sight it's too scary to go for it.