Mavic Pro Platinum Magnetic Interference Warning

[Conservative Nihilist]

Yesterday I test flew for the first time my recently acquired Mavic Pro Platinum. My drone landing pad is a 4-foot on edge plywood sheet standing on foot-tall wooden legs, with one at each corner and one at the center to prevent the plywood sheet from sagging in the middle. Those table legs are affixed with metal nails, which was a concern until I successfully flew several different drones off that table with no issues on takeoff or landing.

I have launched my Phantom 3S,, Phantom 3 Pro, and Mavic Pro from this plywood landing pad numerous times with no anomalies observed, but that changed when I flew the Mavic Pro Platinum from the same platform. Right away "magnetic interference" messages appeared on my iPad's Litchi screen, and the tail light flashed red and orange, as opposed to the green tail light that illuminates steadily on the Mavic Pro, whose Litchi screen issues no magnetic interference error messages when launched from the same exact wooden platform.

I happen to own a Fimi X8 2020 drone that regularly issues magnetic interference error messages, but because writers in a forum devoted to that drone reported no adverse consequences to simply ignoring those warnings and launching the drone, I decided to launch this Mavic Pro Platinum on a short test flight within visual range. In both GPS Position Mode and in Sport Mode, the Mavic Pro Platinum performed flawlessly in every regard except for the color of that tail light, which alternated between red and orange, rather than the expected green color.

Next, I sent the Mavic Pro Platinum on a 15-minute pre-planned Litchi mission that lay within signal reach of the controller. Again, there was no indication that the drone's performance and ability to follow a GPS-defined flight path were in any way compromised by those mysterious magnetic interference error messages that kept popping up. All this brings me to my question, which is whether in fact magnetic interference error messages can in some instances be ignored at no cost in terms of degraded performance or Litchi mission reliability. I would be grateful for any experiences that can be shared on this topic.

 

[Meta4]

whether in fact magnetic interference error messages can in some instances be ignored at no cost in terms of degraded performance or Litchi mission reliability.

When your compass warns you of magnetic interference, that's a sign that there is a potential problem.
Your biggest worry is that one day you place the drone close to the offending steel nail, but not so close that the magnetic field is obviously stronger than the earth's normal magnetic field, which would trigger a compass warning.
If the compass sensor is deflected toward the nail, but with a field strength that the compass doesn't recognise as a problem, you could find out what a yaw error does to ruin your drone flying.

Search here for yaw error to see some reports of what that involves.

I'd strongly advise you to get rid of the steel nails and replace them with something that won't affect the compass.
Something like copper or bronze boat nails might be an option.

 

[Conservative Nihilist]

Thanks for this clarification, Meta4. Looks like I may need to swap out those nails just to be on the safe side. It is odd that none of my other DJI drones gave any indication of there being significant magnetic interference when lauched from he same platform. I might go ahead and carry out a compass calibration on this MPP to see if that will make a difference in the meantime.

It just occurred to me that the Mavic Pro Platinum does have a couple more collision sensors than does the regular Mavic Pro1, so I wonder if those extra sensors increase the drone's susceptibility to magnetic interference. At some point I may temporarily turn off those sensors to see if the error messages go away.

 

[Meta4]

Thanks for this clarification, Meta4. Looks like I may need to swap out those nails just to be on the safe side. It is odd that none of my other DJI drones gave any indication of there being significant magnetic interference when lauched from he same platform

WIth small pieces of steel, like the head of a nail, the difference between setting off a compass warning or not could be a matter of a fraction of an inch closer or further from the compass sensor.

I might go ahead and carry out a compass calibration on this MPP to see if that will make a difference in the meantime.

It won't make any difference and isn't needed.
If your drone's compass wasn't properly calibrated, you'd know it.
Magnetic fields external to the drone are irrelevant to compass calibration, which only identifies and measures the magnetic fields that are part of the drone.

It just occurred to me that the Mavic Pro Platinum does have a couple more collision sensors than does the regular Mavic Pro1, so I wonder if those extra sensors increase the drone's susceptibility to magnetic interference.

And those sensors are visual or infrared.
None of them is affected by magnetic fields.

 

[Conservative Nihilist]

Good to know that the anti-collision sensors have no bearing on magnetic interference errors, so I won't need to look there for a solution. Likewise for the compass calibration I thought might help. For my next flight, I'll be sure and place the drone further away from that nail located dead center of the table surface, and I'll report back here if that off-center placement solves this puzzle.

It is reassuring to know that regardless of the questions asked about a Mavic Pro, there are old hands present in this forum with lots of experience who are willing to shed light for the benefit of less experienced drone hobbyists. I had no idea that magnetic interference warnings can be triggered by such tiny variations in distance from the drone to a small nail. I owe you a beer for sure Meta4, and I thank you kindly for taking a moment to clear up these ignoramus questions I needed to ask.

 

[Meta4]

It's all a good learning opportunity for others too.

 

[kndll]

I once used my backpack to launch from , inside the backpack was my tablet cover --- with the magnet closure --- enough to cause my PS3 to crash on take off , tablet cover has never been used since with any of my drones .

 

[Zonian]

I used to launch my MP1 from my wooden deck. Once I got the Magnetic Interference message, and when I investigated, I realized that I had placed the MP1 directly over a row of deck screws. I moved the MP1 6 inches or so so that it was between rows of deck screws, and the message went away.

 

[sar104]

Yesterday I test flew for the first time my recently acquired Mavic Pro Platinum. My drone landing pad is a 4-foot on edge plywood sheet standing on foot-tall wooden legs, with one at each corner and one at the center to prevent the plywood sheet from sagging in the middle. Those table legs are affixed with metal nails, which was a concern until I successfully flew several different drones off that table with no issues on takeoff or landing.

I have launched my Phantom 3S,, Phantom 3 Pro, and Mavic Pro from this plywood landing pad numerous times with no anomalies observed, but that changed when I flew the Mavic Pro Platinum from the same platform. Right away "magnetic interference" messages appeared on my iPad's Litchi screen, and the tail light flashed red and orange, as opposed to the green tail light that illuminates steadily on the Mavic Pro, whose Litchi screen issues no magnetic interference error messages when launched from the same exact wooden platform.

I happen to own a Fimi X8 2020 drone that regularly issues magnetic interference error messages, but because writers in a forum devoted to that drone reported no adverse consequences to simply ignoring those warnings and launching the drone, I decided to launch this Mavic Pro Platinum on a short test flight within visual range. In both GPS Position Mode and in Sport Mode, the Mavic Pro Platinum performed flawlessly in every regard except for the color of that tail light, which alternated between red and orange, rather than the expected green color.

Next, I sent the Mavic Pro Platinum on a 15-minute pre-planned Litchi mission that lay within signal reach of the controller. Again, there was no indication that the drone's performance and ability to follow a GPS-defined flight path were in any way compromised by those mysterious magnetic interference error messages that kept popping up. All this brings me to my question, which is whether in fact magnetic interference error messages can in some instances be ignored at no cost in terms of degraded performance or Litchi mission reliability. I would be grateful for any experiences that can be shared on this topic.

This thread seems to be full of speculation on an issue that is easily determined by actual data. It's trivial to identify the source of the magnetic interference message. Firstly - what are the compass interference values in the app - are they high or within spec? Secondly - is the aircraft heading, as displayed on the app, correct? Thirdly - does this only occur when powered up at that location, or does it always show the error?

 

[MAvic_South_Oz]

Thirdly - does this only occur when powered up at that location, or does it always show the error?

Exactly.
Try flying it from a clear ground launch spot (green oval grass) to see if the problem is gone and lights / map orientation is normal.

 

[MAvic_South_Oz]

It just occurred to me that the Mavic Pro Platinum does have a couple more collision sensors than does the regular Mavic Pro1

It does ?
I thought the M1P and MPP were basically the same bar the colour, props, and firmware settings for motor esc settings.

 

[Conservative Nihilist]

This thread seems to be full of speculation on an issue that is easily determined by actual data. It's trivial to identify the source of the magnetic interference message. Firstly - what are the compass interference values in the app - are they high or within spec? Secondly - is the aircraft heading, as displayed on the app, correct? Thirdly - does this only occur when powered up at that location, or does it always show the error?

Hello Sar104, and thanks for this response. The aircraft heading did appear to be correctly oriented along the Litchi flight path the drone traveled during my initial test, which led me to conclude that the detected magnetic interference was not significant enough to disorient the Mavic even during an autonomous flight. I'll take a look again today when I launch another test flight, to see how the drone orients itself for a regular flight that is not pre programmed with Litchi.

I use Litchi exclusively, and never DJI Go or DJI Go4, though I doubt whether this could be a contributive factor that could explain those magnetic interference error messages.

@Mavic South Oz I will run another test flight today with the launch pad a piece of plywood with no nails in it, to see if that will silence those error messages. Regarding the collision avoidance sensors, your correction of my wrong presumption is appreciated. I checked the manuals of both Mavic models, and they are indeed identical with respect to the number and location of those collision sensors.