Of course not, it's moving about 1000mph... can't you feel the breeze on your face?
Mavic 2 Pro Drops Into the Ocean at Takeoff
- Thread starter Tim3459575
- Start date
That looks like a great place for boating and for drone photography.
Your drone had good GPS location data by the time you started the motors.
It reported recording the homepoint at 0.2 seconds.
The drone detected the boat's movement through the changing location data.
At the end of the data (only 3.5 sec), the drone knew it was 16 ft from where you started up.
With no joystick input from you, it sensed that it was hovering and drifting away and wanted to correct that, by flying back to the launch spot.
Once the motors had started, you needed to get the drone into the air where it could hover and wait for you to give it some control input and start flying.
But restraining it while its trying to hold position, was what caused the problem.
To be more specific, and as I suggested previously, at 3.5 s the aircraft roll went to 109° due to the operator attempting to restrain it from holding position, and the FC shut down the motors due to attitude limit exceeded. In other words the operator dropped it into the water, motors off.
... and make it somewhat visual.
Here is what happened pictured in a chart & on a sat picture.
To the left, where the light green background color switch to darker green is from where the HP is recorded. By that the distance traveled from the HP (red graph) & heading speed (green graph) starts to be logged. The blue & purple graph is the logged AC Attitude in pitch & roll.
So after the AC had been moved away from the HP 4,59m it finally broke lose from the OP's hands & rolled to a max logged angle of 108,7 degrees which, as said earlier, meant that the motors shut off ... which is confirmed by the OSD:isMotorUp state switches from True to False just in the end (3,5sec) where I've placed the marker in the chart.
(Click on the chart to make it larger)
And here from a sat picture showing the path of AC movement (red, with a green bar to show the yaw direction) with where the HP & mobile device (with it's own measured position) was in relation to the AC in the end of the log.
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Thank you for the detailed analysis ! Once I get my new drone I’ll make sure to let it go soon as it establishes basic lift. The programming logic does seem strange though, in that it would tilt 109 degrees, then shut off motors, in an effort to get back to home point.
Will be getting either Air2s or M2P. I wonder if the Air would be safer for boat launching. Have the accessories for the M2P and believe has a better camera due to aperture control. But perhaps the Air has better flight control.
It's two separate things.
With the drone wanting to get back to where it thought you wanted it to hover and you fighting against it, the drone ended up in a position where it rolled >90° which is what shut down the motors
They both have similar flight controls, but the Mavic 2 uses the DJI Go4 app which is quite a bit better than DJI Fly, which the Air 2S uses.
The Air 2S has more recent frills in automated flight modes.
After reading your first post, my first thought was why use Auto takeoff on a boat? Power the drone on, hold it out at arm's length, arm the motors, and firewall the throttle...
Once the motors are armed the drone thinks it needs to hold its position in 3 dimensions. Any movement big enough for the drone to think that it isn’t at the motor arming point will cause an attempt to get back to that point. Going from CSC to full lift will take a measurable time during which the drone will try to stay at its home point.
Disclaimer: I've never launched from a boat. But over the last four years on this and the Phantom Pilots forum I've read dozens, maybe a hundred or more posts of people who do. I've never heard anyone say they use Auto takeoff, and to me that just wouldn't make any sense to do so. Those same people launch from a boat, so there must be a way.
If you throttled down the boat to an idle and wait till it stops moving through the water that would be a heck of a lot better than being underway. And if you floor the throttle it won't matter if the drone wants to move a little backwards anyway - it's already under its own power.
eta: Auto takeoff is only going to apply enough power to get the Drone four or five feet in the air and hover. Throttle to the wall, it's going to pull itself out of your hand and rise... that's also the best way to take off from the ground in windy / gusty conditions
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Don't hold onto the drone. It should just be resting on your hand or a platform. Let it take off on it's own. It should just lift off and hover. I also don't think it would be a good idea to let a drone lift off from the boat, if the boat is moving faster than the drones maximum speed. It might be ok, but I'm not positive. It may cause the drone to tilt too much. Maybe someone else will know.
On the ground that only takes me about two seconds flat... I fly with the controller on a lanyard and can CSC and throttle up with my left hand... which would also be an excellent idea on a boat.
What does CSC stand for ? Sounds like I shouldn’t use auto takeoff and also hold it lightly so it can lift off as soon as it’s got enough lift. Being a sailboat and trying to capture images under sail makes stopping the boat very difficult (vs a power boat). Attached is recent sample image.
Attachments
CSC is an acronym for Combination Stick Command... a fancy way of saying pull both sticks all the way down and to the inside (or outside)... to me inside is easier with one hand... a quick convenient way to arm the motors.
With the controller on a lanyard I let it dangle about belly button height, lightly hold the Drone at arm's length above my head with my right hand, pull both sticks down with my left forefinger and pinky. As soon as the motors arm hit the throttle hard (left stick) and it's gone baby!
Also, before you do any of the above, power on the drone and give it a few minutes to acquire enough satellites.
so I assume “arming” (using CSC) initiates liftoff sequence which powers up the props (similar to auto takeoff slider) which I immediately follow with full throttle ascend.
Arming doesn't 'initiate liftoff sequence', it just starts the motors at an idle, then you can take off with the throttle (left stick)... please practice this in your back yard, HS football/baseball/soccer field, or a nearby park if it has an open space.
Also, while you're practicing this, you can stop the motors by pulling all the back on the left stick. BTW, don't do a CSC while the drone is in the air - CSC also stops the motors if they are running. ?
Also, while you're practicing this, you can stop the motors by pulling all the back on the left stick. BTW, don't do a CSC while the drone is in the air - CSC also stops the motors if they are running. ?
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Combination Stick Command - an unlikely combination of stick movements used to command the motors to start or stop. RTFM! In the case of our drones the command to start is accompanied by the words “Take off”. The drone is then holding position waiting for a command. In flight, the CSC will stop the motors. Holding the left stick hard down (in mode 2) does not stop the motors unless the drone is on the ground, hand, table or whatever you’ve decided to land on.
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BTW, someone said above:
Good Luck!
Resting on your palm, on a boat = bad idea. Gently hold it from underneath - another thing you should practice.
Good Luck!
The mobile device the RC is connected to gives the audio message “take off” on issuing the CSC command. Flying without a mobile device is silent other than for beeps and alarms but you’ll certainly fly VLOS.
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