DJI's on hand landing.

[Meta4]

in the event of a lost or damaged prop, or props during flight ,that causes the drone to tumble as it descends, is just part of the system, to protect whatever the drone eventually connects with ,when it reaches the end of its descent,and to some extent ,the spinning remaining props, causing further damage to the structure of the drone itself, such as landing in a tree for instance

Lose a prop in flight and the motors will continue to run.

 

[Meta4]

So if you just hold it, the props will stop automatically?

You lower the drone into your grip and hold it while holding the left stick down.
After approx 2 seconds with the stick down and the drone not able to descend, the motors shut down.

 

[Yorkshire_Pud]

I broke 3 propellers landing on narrow boats. So I tried a hand landing, and it went well. I rotated the drone upside down to stop the propellers. So I emailed DJI this.

I've damaged a number of propellers on recent flights, mainly landing on narrow boats.
If I hand catch my drone, is it ok to turn it over so it's facing down, to stop the propellers? Since I fly with a tablet, I can't really operate Fly while I'm holding my drone. Thanks, Steve

This was their response.

Please don't catch the aircraft when the propeller is rotating. It may hurt your hand. We recommend you to take off and land the drone on the ground.

So when I'm on a boat, not because I want to be, I should still take off, and land, on land. Great advice!

So I'm on a boat, anchored in the ocean. How do I take off on land? Swim to shore, holding the drone in my teeth?

The grab and twist method of catching the drone and stopping its motors need only be used where the catcher/drone is experiencing significant? movement.
That movement is sensed by the drone's sensors and it thinks it is still airborne, under normal circumstances the drone will not stop its motors whilst airborne.

I agree that twisting the drone whilst the drone is fighting you stresses the drone but on an ocean going boat which rises and falls, rocks about two axis and moves horizontally you have no other option unless you wish to permanently enable the emergency stop response to the CSC stick position and executing a CSC is awkward when using only one hand, even more so on a literally rocking and rolling boat. Permanently enabling that option is risky, drones have been lost that way when the pilot inadvertently put the sticks in the CSC position.

The normally recommended way of stopping the motors is, as has been suggested, to simply hold the throttle closed once the drone has been caught but that REQUIRES the catching hand to be still and you may not be able to achieve that on a boat. Even if you were on a canal/narrow boat on a canal the forward motion of the boat maybe enough to prevent the latter from stopping the motors.

 

[Filmarik]

The grab and twist method of catching the drone and stopping its motors need only be used where the catcher/drone is experiencing significant? movement.
That movement is sensed by the drone's sensors and it thinks it is still airborne, under normal circumstances the drone will not stop its motors whilst airborne.

I agree that twisting the drone whilst the drone is fighting you stresses the drone but on an ocean going boat which rises and falls, rocks about two axis and moves horizontally you have no other option unless you wish to permanently enable the emergency stop response to the CSC stick position and executing a CSC is awkward when using only one hand, even more so on a literally rocking and rolling boat. Permanently enabling that option is risky, drones have been lost that way when the pilot inadvertently put the sticks in the CSC position.

The normally recommended way of stopping the motors is, as has been suggested, to simply hold the throttle closed once the drone has been caught but that REQUIRES the catching hand to be still and you may not be able to achieve that on a boat. Even if you were on a canal/narrow boat on a canal the forward motion of the boat maybe enough to prevent the latter from stopping the motors.

Let's not turn hand catching into a rocket science. It is simple and straight forward procedure. Practicing on a solid ground is always a good idea before attempting to do it on a rocking boat.
Bring the drone above your outstretched hand with palm facing up. When the drone recognises your palm (about 2 to 3 feet away), hold the throttle stick all the way down and the drone will descend slowly into your palm. Grab it around the middle of the body with bent fingers so they CAN NOT come into contact with spinning propellers while keep holding the throttle stick down. The motors will stop after 2 seconds if you hold the drone STEADY.
It is really as simple as that.
If you do not want the drone to pause before descending into your palm, turn the landing protection off and you are in full control while bringing the drone right into your palm. This is for experienced and confident fliers only!!!
Practice makes perfect. Enjoy!!

 

[Yorkshire_Pud]

I have a strong suspicion that your propsed method will not work,on a boat on the open ocean with waves I suspect the drone will sense movement and refuse to stop its motors. The CSC and the twist are, I think, the only methods that will work.
Where is the rocket science in that.
Besides, that I last read it was not possible to turn landing protection off in the mavic 3 series drone, has that changed ?

 

[rgarjr]

I have a strong suspicion that your propsed method will not work,on a boat on the open ocean with waves I suspect the drone will sense movement and refuse to stop its motors. The CSC and the twist are, I think, the only methods that will work.
Where is the rocket science in that.
Besides, that I last read it was not possible to turn landing protection off in the mavic 3 series drone, has that changed ?

I have the smart landing parameter off using drone hacks on the Mavic 3 Pro

 

[Yorkshire_Pud]

I have the smart landing parameter off using drone hacks on the Mavic 3 Pro

Ah ok.

 

[Filmarik]

I have a strong suspicion that your propsed method will not work,on a boat on the open ocean with waves I suspect the drone will sense movement and refuse to stop its motors. The CSC and the twist are, I think, the only methods that will work.
Where is the rocket science in that.
Besides, that I last read it was not possible to turn landing protection off in the mavic 3 series drone, has that changed ?

Sorry I was not replying to you you personally but generally to the entire thread. The landing protection off is now an option in the latest FW. Not sure what boat you were on but I hand cought M3P many times while on a small dingy. The outstretched arm can compensate the boat rocking motion sufficiently enough for the drone to stop the motors.

 

[TheRock]

I had a friend, who lives and works on his boat, just about take his nose off (surgery was required) when a wave shifted the boat during a try for a hand catch. If it is not an open boat, land on the roof. Put a rubber mat of some sort up there prior to bringing it in so it doesn't slide. Or hand catch and take your chances. Make sure your insurance is paid up.

 

[Filmarik]

I had a friend, who lives and works on his boat, just about take his nose off (surgery was required) when a wave shifted the boat during a try for a hand catch. If it is not an open boat, land on the roof. Put a rubber mat of some sort up there prior to bringing it in so it doesn't slide. Or hand catch and take your chances. Make sure your insurance is paid up.

Sorry to hear that. That must have been terrible !!
I always hold my arm above my head when hand catching and with wind pushing the drone away from me not towards me! If I may say so, catching the drone in front of the face isn't the smartest idea on a solid ground let alone on a rocking boat

 

[Squidinc]

In my opinion, to hand catch, you have to turn obstacle avoidance off first. That's what I do.

Agree. I hand catch & launch in many different locations. Obstacle avoidance needs to be off. I injured myself in my pic because I foolishly tried to catch it from the topside instead of underneath.

 

[Filmarik]

Agree. I hand catch & launch in many different locations. Obstacle avoidance needs to be off. I injured myself in my pic because I foolishly tried to catch it from the topside instead of underneath.

99% of time I fly with obstacle avoidance off so it did not even come to my consideration. I agree with you though.

 

[djwak59]

My own opinion here, but, NOT catching my drones with my hand was probably the first thing I learned, and years later, I STILL don’t do it.

 

[Yorkshire_Pud]

The landing protection off is now an option in the latest FW.

 

[jwilson]

Agree. I hand catch & launch in many different locations. Obstacle avoidance needs to be off. I injured myself in my pic because I foolishly tried to catch it from the topside instead of underneath.

Yea, I can see why topside would be dangerous. Not much room to avoid the props.

 

[Yorkshire_Pud]

I do not believe it stresses anything.

That's your choice but have you ever heard of a gyroscope and what happens when you try to change the direction of the gyroscope's axis of rotation ?

If it doesn't stress things then it would take no torque to rotate the drone onto its side or back, from memory that is not the case.
Not only are you fighting the gyroscopic effect of the props but the drone itself will attempt to remain level by changing motor speeds.
Of course the drone is designed to withstand these stresses, it has to be since similar actions are how it manoeuvres, but flipping the drone onto its back takes things to extremes.

Case in point, it has been noted the props of some drones ( mavic mini ? ) will, in certain circumstances, clip the drone's shell.
If this is not caused by the flexing, and therefore stressing, of various components during 'acrobatics' what causes this to happen ?

Disbelieve what OMM has said if you want but I think you are mistaken.

 

[TheRock]

Sorry to hear that. That must have been terrible !!
I always hold my arm above my head when hand catching and with wind pushing the drone away from me not towards me! If I may say so, catching the drone in front of the face isn't the smartest idea on a solid ground let alone on a rocking boat

I don't believe it was in front of his face until the wave hit. They had to use soft skin from his underarm to use for his nose. He is fine now.