How precise is your RTH?

[kloogee]

I find that most drone pilots make two big mistakes related to this. First, they believe they can run their controller on a smartphone that isn't an Apple product. DJI specifically states to use iphones or ipads. The IOS system is the best for this and runs more accurately. Android is not so good, and can cause flight failure too.Second, allow the drone to hover for a half minute after it launches, so it can get its fixes. My drone always RTH withing 6 inches, even in light breeze.

I think you have completely misunderstood the "Made for iPhone" sticker that is on many of DJI's packaging. This doesn't mean that DJI is specifically recommending iPhones over Androids. This is simply the Apple logo for their developer certification program. It means that DJI has paid Apple a bunch of money and is certifying that they are meeting certain requirements of the Apple program to help ensure good compatibility with Apple devices. Unfortunately, there is no similar developer certification program for Android. If there were, I imagine DJI would do that certification process as well.

You can learn more about the Apple Developer Cerfication Program here: MFi Program - Apple Developer

 

[PatrickG]

i did the test after calibrating the compass
20 cm from the take off zone after a fly in many direction

 

[kloogee]

i did the test after calibrating the compass
20 cm from the take off zone after a fly in many direction

Compass calibration shouldn’t affect RTH precision.

 

[DanMan32]

Was that before or after PL was added to the firmware? PL is automatic on M2, assuming you flew up high enough before going out.

 

[DanMan32]

My m2z requests I recalibrate for 90% of all flights even when launching from my house most flights.

It might need demagnetising.

 

[lrsn]

I, like a few others on this thread, don't agree with Joe Boudreault in post #36 of this thread. I have never used anything but Android Tablets and Smartphones with my P3P, I1V2, P4, MP, and P4PV2.0, all of which I still have. For my M2P I use my DJI Smartcontroller which also happens to be Android!

 

[zappy54]

I have never been happier changing from Android to iOS no need to think about the dreaded usb charging the Android device or the dreaded usb permission full stop.......

 

[marine9]

Make a conscious effort to ensure you are in GPS mode before you take off. Very important to prevent flyaways.

 

[parkgt]

It’s good practivpce to calibrate the compass before each flight. My M2P returns to within 1 m.

I don't unless asked to and my MP2 is usually within 6" to 12".

 

[parkgt]

Make a conscious effort to ensure you are in GPS mode before you take off. Very important to prevent flyaways.

I never have to make a "conscious effort" mine has never taken off without being in GPS mode?

 

[Meta4]

I have seen people post that they never calibrate their compass. This can lead to disaster. While if you are flying in the same general area all the time, it's not a problem. But if you take it on a trip, then it may be. Magnetic north is almost never the same as true north. This compass deviation will vary as you travel east or west. Where I live the deviation is only a few degrees and no problem. But when I took my drone to Utah, there is significant compass deviation and so I calibrated my drone before flying. What happens is that if there is a significant variation, the GPS is saying north is one way and the compass is saying north is in a different direction which wreaks havoc with the IMU and has caused pilots to lose control of the aircraft immediately upon takeoff. I think the poster is correct in that if there such variation, the aircraft will give you a warning but even if it doesn't it is better to be safe than sorry though I don't recall getting a warning from the App before the flight when I went to Utah. Taking a few seconds to calibrate the compass is well worth it to prevent the loss of a valuable aircraft.

Compass calibration has nothing to do with magnetic deviation at all or how far you travel .
The only thing compass calibration does is to identify and measure the magnetic fields that are part of the drone so they can be ignored.
This ensures that your compass readings are accurate.

 

[Thomas B]

I only calibrate compass if the M2P requests it, and doesn’t really apply for the question at hand.
As far as accuracy of RTH:
I ascend to about 4-10’ and wait 2 or 3 seconds for the voice confirmation that home point is recorded. I then get a precision landing that is uniformly within 2-3” of TO point.

 

[PAW]

I only calibrate compass if the M2P requests it, and doesn’t really apply for the question at hand.
As far as accuracy of RTH:
I ascend to about 4-10’ and wait 2 or 3 seconds for the voice confirmation that home point is recorded. I then get a precision landing that is uniformly within 2-3” of TO point.

Ditto

 

[kloogee]

I only calibrate compass if the M2P requests it, and doesn’t really apply for the question at hand.
As far as accuracy of RTH:
I ascend to about 4-10’ and wait 2 or 3 seconds for the voice confirmation that home point is recorded. I then get a precision landing that is uniformly within 2-3” of TO point.

I would highly recommend for most people to wait for the home point to be recorded before launching. Not doing so significantly increases your risks of a bad outcome. This is especially important for newer operators that don't have a ton of experience.

 

[Thomas B]

I would highly recommend for most people to wait for the home point to be recorded before launching. Not doing so significantly increases your risks of a bad outcome. This is especially important for newer operators that don't have a ton of experience.

Agree that home point recording is important, especially if signal communication to the drone is lost.
I don’t think the drone will record accurate home point until after TO, hence my advise to launch, hover, and wait 2-3 seconds for the “home point recorded” message.

 

[DanMan32]

After paying closer attention, mine says homepoint updated almost as soon as there's a GPS lock and IMU fully initialized.

 

[paulatkin73]

i did the test after calibrating the compass
20 cm from the take off zone after a fly in many direction

other day i started it from the palm of my hand, flew half mile away above the forest, took some panos, then pressed RTH - it returned exactly back into my hand, i did not walk away or moved at all.
i did not stop it to hover, just turn it on while holding it in the hand, wait for the GPS mode to come up on the screen, to say that home point is set, then i flip the switch on the screen to start motors and take off vertically up to 100m or so.

 

[Drgnfli]

I've M2Z and generally I took off vertically up to 25m, then move horizontally.

I always do RTH, as I enjoy its auto landing part. Most of the time RTH is accurate up to less than an inch and sometimes 100% accurate.

Yeah, I RTH at least once a week! I think it is fun and really amazes those watching. Except for that noisy, continuous beeping I would do it more often ! !

 

[Drgnfli]

Be sure to calibrate your compass before takeoff. Lift off to 30 pause and rotate 360 degrees, my drone lands spot on almost every time.

I don't get this "calibrate the compass" everyone seems to do all the time. I've calibrated my MP ONCE in two years only because I wanted to learn how to do it. Other then that, my MP never, ever requires me to calibrate the compass & I never have a problem with its location or RTH accuracy...?

 

[Paulman]

Flew m2z this am from home and as usual came up with "magnetic inter " and 're calibrate compass' which made it happy and move from opti to gps and fly well.