How to force OPTI mode for boat use?

[Xanth]

Surprised I can't find anything on the forum about this, but I'm on a large ship and I want to take some shots while the ship is moving. My fear is that in GPS mode as soon as the Mavic is off the deck it'll head off the back of the boat.

Staying in OPTI mode seems the obvious solution, but there's no mention of how to intentionally do that in the manual.

What am I missing?

 

[msinger]

What am I missing?

Nothing. It's not possible to manually switch to OPTI (ATTI) mode.

 

[chris956]

Surprised I can't find anything on the forum about this, but I'm on a large ship and I want to take some shots while the ship is moving. My fear is that in GPS mode as soon as the Mavic is off the deck it'll head off the back of the boat.

Staying in OPTI mode seems the obvious solution, but there's no mention of how to intentionally do that in the manual.

What am I missing?

Why dont you just set the home point as the remote control ??

 

[Andrew F]

Nothing. It's not possible to manually switch to OPTI (ATTI) mode.

Which is a travesty.

 

[Andrew F]

Why dont you just set the home point as the remote control ??

That requires your phone / tablet to have a strong GPS signal. But it works. Regardless. Flying from a moving ship is a risky venture. If you get into a legit RTH situation - good luck.

 

[Xanth]

That requires your phone / tablet to have a strong GPS signal. But it works. Regardless. Flying from a moving ship is a risky venture. If you get into a legit RTH situation - good luck.

Good point, but RTH really isn't the problem since I don't intend to ever get more than 20 ft off the deck. I'd like to shoot some ship-board activities in tripod mode like you would indoors. My assumption (w/o testing for obvious reasons) is that on deck, GPS would send the bird like a bullet into, or over, the back of the boat.

I have considered using Activetrack Trace, but since it has to be engaged in flight, I figured the Mavic might be gone before I could even identify the target.

Then there's the little matter of landing. I wonder if the Mavic would even do it if GPS tells it there's significant horizontal velocity.

Weird stuff

 

[Andrew F]

Good point, but RTH really isn't the problem since I don't intend to ever get more than 20 ft off the deck. I'd like to shoot some ship-board activities in tripod mode like you would indoors. My assumption (w/o testing for obvious reasons) is that on deck, GPS would send the bird like a bullet into, or over, the back of the boat.

I have considered using Activetrack Trace, but since it has to be engaged in flight, I figured the Mavic might be gone before I could even identify the target.

Then there's the little matter of landing. I wonder if the Mavic would even do it if GPS tells it there's significant horizontal velocity.

Weird stuff

Oh! Then just turn off RTH and have the Mavic hover in place if gps signal is lost. RTH is a very bad idea in that circumstance.

 

[Kilrah]

I would simply not use a Mavic for such a job. Get a Phantom that can be forced in ATTI mode.

 

[Xanth]

Oh! Then just turn off RTH and have the Mavic hover in place if gps signal is lost. RTH is a very bad idea in that circumstance.

Hover in place IS the problem.

 

[Xanth]

I would simply not use a Mavic for such a job. Get a Phantom that can be forced in ATTI mode.

It's not a job, it's a vacation. And I've taken my Phantom on trips before and it's a pain. Convenient and capable were supposed to be big Mavic selling points.

Beginning to wonder if DJI is Chinese for "too smart by half."

Next thing we'll learn is that the Spark won't ever work on foggy days just in case you should decide to gesture.

 

[Malavic]

Surprised I can't find anything on the forum about this, but I'm on a large ship and I want to take some shots while the ship is moving. My fear is that in GPS mode as soon as the Mavic is off the deck it'll head off the back of the boat.

Staying in OPTI mode seems the obvious solution, but there's no mention of how to intentionally do that in the manual.

What am I missing?

There is no way to do it except to block the GPS. Funny but Anthony Cumia took his Mavic on a Cruise recently and flew it in his suite without a problem. He took it out on the balcony and as long as it was over the balcony, no problem. The moment he moved it off the balcony, it shot to the back of the ship as the GPS locked on. He was able to quickly stick down land it on the putting green . His suite valet had strong words for him about drone use being prohibited. The Valet also mentioned that the ship has some anti-drone tech, no idea what that means though.

 

[Andrew F]

Hover in place IS the problem.

Only if you are on the bow. But it's MUCH better than RTH in your case. You can always manually abort. Be sure to be comfortable switching to sport mode.

 

[dbyantis]

Good point, but RTH really isn't the problem since I don't intend to ever get more than 20 ft off the deck. I'd like to shoot some ship-board activities in tripod mode like you would indoors. My assumption (w/o testing for obvious reasons) is that on deck, GPS would send the bird like a bullet into, or over, the back of the boat.

I have considered using Activetrack Trace, but since it has to be engaged in flight, I figured the Mavic might be gone before I could even identify the target.

Then there's the little matter of landing. I wonder if the Mavic would even do it if GPS tells it there's significant horizontal velocity.

Weird stuff

I don't want to hijack the main thread, but I need to understand the real issue here, I would always prefer to fly with GPS, I also assume that you can get the SAT lock from a moving ship, so just wait for full GPS mode and you will have complete control of it, I do understand why there is a concern about it flying away once it gets GPS, you can turn off RTH, so it won't go to the lasy known home.Thanks.

 

[peros550]

If I have understood correctly, the Mavic locks its position when GPS is on. It tries to stay there no mater what.

If the ship is moving, it will move forward and the Mavic will try to stay locked behind. The effect will be like the Mavic was moving backwards because you the pilot are stand still on a forward moving ship.

Whoever tries that, pay attention to big metal areas, they might mess with Mavic's compass.

 

[Xanth]

This has been a unique thread. I feel like 2/3 of the participants understand that GPS generates basic location coordinates relative to the globe, and the other 1/3 seem to ascribe GPS and RTH an almost sentient ability to know where you are, were and will be. To help, I would suggest an experiment. Get in your car and place the Mavic on the passenger seat. Power up and idle the props. Wait for GPS mode, then slowly start driving the car and see what your bird does.

Many thanks for the Anthony Cumia story. That confirms everything I suspected would happen. Thank goodness there was enough boat so that when the emergency kill command finally took effect he wasn't over the drink. I think my first instinct in that situation would be to climb and hope to miss heads, smokestacks, etc. (Especially given the fact that holding the GPS lock might cause the Mavic to fly with full prop velocity to the back of the boat.) Then once it was high and clear bring it in for a hand-grab landing.
FWIW

 

[MavicAyr]

I work on a ship and had the same idea as yourself in blocking GPS to allow easy takeoff and landing. With the most recent firmware the Mavic automatically assumes that I'm in a NFZ. I downgraded to .400 and it'll work but the whole ATTI thing on a moving large ship with various winds coming through the superstructure caused me no end of stress.
I've successfully hand launched and hand caught from a utility boat away from my main ship. The benefit being I can stop the utility boat and slowly fly into range to grab the Mavic.

 

[Xanth]

I work on a ship and had the same idea as yourself in blocking GPS to allow easy takeoff and landing. With the most recent firmware the Mavic automatically assumes that I'm in a NFZ. I downgraded to .400 and it'll work but the whole ATTI thing on a moving large ship with various winds coming through the superstructure caused me no end of stress.
I've successfully hand launched and hand caught from a utility boat away from my main ship. The benefit being I can stop the utility boat and slowly fly into range to grab the Mavic.

Very interesting! I would think flying ATTI in that situation would be a real test. Were you ever able to fly in OPTI? That seems like it should work close to the deck.

I decided to do some testing on deck during my boring "at sea" day, and had my son hold the Mavic while I spun up the props. Sure enough, once we found a way to hold it that wasn't blocking any of the sensors, it went full rotors trying to hold GPS lock. That really wasn't surprising. What was surprising was how worthless the emergency stop (sticks down and in/out) was. What kind of emergency isn't made worse by 5-10 secs at full power before cutting...if at all? I thought I was going to have to pull off the battery because the props kept stopping and restarting again. Having the stick controls the same for both emergency stop, and start, is worth rethinking. That said, this only happens with my Mavic. My Inspire and old Phantom kill immediately.

All this could be solved if DJI created a certification program that would allow the certified to fly without all the restrictions made necessary by the certifiable.

 

[Robbyg]

The problem is not taking off. You can always take off by just making sure you have enough clearance between the Mavic and the back rail so that you can quickly throttle up and clear the railing.

The bigger problem is when you try to land! Just like the video of the guy trying to land in the bed of a moving truck you are going to find you have to match the forward speed of the boat but the minute you ease up and try to go into landing mode the Mavic is going to start going backwards very quickly.

You could CSC the Mavic one foot from the deck but its still going to go backwards a few feet. Short of hand grabbing it, which I would not recommend, I can see no easy way of doing this short of building some sort of padded cardboard box to catch the Mavic in.

Rob

 

[dwallersv]

Hover in place IS the problem.

^This.

Instead of trying to keep the aircraft "stationary" over the boat deck by using ActiveTrack, which will be problematic at best in this situation, how about trying the Follow mode? So long as you have good GPS on your smart device connected to the RC, you can set it up to follow you and it will then more or less "hover" over the moving deck when you let go of the sticks, but still be able to control and move it around.

Of course, as someone else mentioned, be sure and set RTH to the RC location too, just in case anything goes wrong.

 

[gregw]

Good point, but RTH really isn't the problem since I don't intend to ever get more than 20 ft off the deck. I'd like to shoot some ship-board activities in tripod mode like you would indoors. My assumption (w/o testing for obvious reasons) is that on deck, GPS would send the bird like a bullet into, or over, the back of the boat.

I have considered using Activetrack Trace, but since it has to be engaged in flight, I figured the Mavic might be gone before I could even identify the target.

Then there's the little matter of landing. I wonder if the Mavic would even do it if GPS tells it there's significant horizontal velocity.

Weird stuff

As far as I know, all cruise ships ban drones from being flown on board... If you do have permission to do this, then please try it out and report here so we all know what to do...

Hovering in place in a moving boat in GPS mode requires you to actually fly the Mavic to match the forward motion of the boat... Since the boat itself is moving, the GPS position is constantly changing, so you will have to "factor" in this while flying... I think the Mavic should be more than capable of keeping up with a cruise ship, and if all else fails, there's always Sports mode.. I would also be wary of taking off directly from the deck since almost everything on the ship is metal... I would definitely start up the Mavic on a plastic deck table and launch from there or hand launch it... Landing on deck should be fine...

I still haven't tried flying the Mavic from a moving boat, but I think the solution to landing is to turn off "Landing Protection" and/or VPS and land manually.. i.e. with the Mavic facing towards the front of the ship, keep right stick forward to match the velocity of the boat, then left stick down to land the Mavic on the deck... You'll need to remember to land slowly since there isn't the hover at 2 feet before landing mode is activated...

My advice is, whatever you do, DO NOT try using any of the "Smart" modes... It may work, but should it loose track of whatever it's supposed to be tracking, there is no telling what the Mavic would do, and you're on a moving ship, with the Mavic surrounded by all that metal..