M2PRO RTH Function and Accuracy

[GMAN007]

As of Aug 2021 -- I have uploaded the most current firmware and remote smart controller for my Mavic 2 Pro. I took the M2P up for a few practice runs and noticed that the precision accuracy location (RTH) isn't what it use to be (despite refreshing RTH point / local compass calibration). I did about 10 landings...with only 3 returning to the exact (original) launch point (pad). The other 7 RTHs were at least 2-3 feet off target.

This has been (in recent times) a surprise to me. Anybody else experiencing this anomaly with the current firmware version ?

 

[Deleted member 103366]

Totally off topic but........unusual decor but it looks quite good.
What is the firmware version number?

 

[Meta4]

As of Aug 2021 -- I have uploaded the most current firmware and remote smart controller for my Mavic 2 Pro. I took the M2P up for a few practice runs and noticed that the precision accuracy location (RTH) isn't what it use to be (despite refreshing RTH point / local compass calibration). I did about 10 landings...with only 3 returning to the exact (original) launch point (pad). The other 7 RTHs were at least 2-3 feet off target.

What you've noticed isn't something about the drone's abilities.
it's about GPS and it's variable inaccuracy.

Your drone has two different systems that are responsible for RTH autolanding precision.
If your drone isn't RTH autolanding within inches, you are not using the Precision Landing feature that uses optical technology.
If you don't launch appropriately for the Precision Landing feature to work properly, the drone will use GPS alone.
GPS is not pinpoint accurate and will place the drone +/- several feet.
That's the nature of GPS.
Recalibrating your compass is completely unnecessary and has no effect on autolanding precision.

But none of this matters much, since you can cancel RTH and land wherever you want rather than depending on unnecessary gimmickry.
You can even fly the drone home yourself.
Just remember to allow sufficient clearance around your launch spot if you are going to let the drone autoland after RTH.

 

[Forensics_Pilot]

Meta4 is exactly right. I just flew 6 missions in the last 2 days and the landings were well within 1-1/2 inches of take off point having just downloaded latest firmware from DJI.

 

[Meta4]

Meta4 is exactly right. I just flew 6 missions in the last 2 days and the landings were well within 1-1/2 inches of take off point having just downloaded latest firmware from DJI.

Precision Landing would have worked with any firmware version, not just the most recent.

 

[benhuntn]

Just my 2 cents but I let my m2pro hover over the launch pad for 15 sec. before I go for my flight. I find that almost always results in an accurate landing if I use rth.

 

[Mark_Y]

I have the best results for a precise RTH auto landing when I take off let the drone hover for 15 seconds, then increase up to 24 feet and let the drone hover again for 15 seconds. This method has always worked well for me.

 

[offtheback]

What you've noticed isn't something about the drone's abilities.
it's about GPS and it's variable inaccuracy.

Your drone has two different systems that are responsible for RTH autolanding precision.
If your drone isn't RTH autolanding within inches, you are not using the Precision Landing feature that uses optical technology.
If you don't launch appropriately for the Precision Landing feature to work properly, the drone will use GPS alone.
GPS is not pinpoint accurate and will place the drone +/- several feet.
That's the nature of GPS.
Recalibrating your compass is completely unnecessary and has no effect on autolanding precision.

But none of this matters much, since you can cancel RTH and land wherever you want rather than depending on unnecessary gimmickry.
You can even fly the drone home yourself.
Just remember to allow sufficient clearance around your launch spot if you are going to let the drone autoland after RTH.

Does the drone take an image of the landing pad upon takeoff to be able to detect it in precision landing?How does it do that?

 

[Ol' Sparky]

Don't know if it still applies for precision landings, but I always fly 20 feet or more directly above take off spot and it always comes back and lands on the pad.

 

[Meta4]

Don't know if it still applies for precision landings, but I always fly 20 feet or more directly above take off spot and it always comes back and lands on the pad.

Here's the Precision Landing section of the manual for the Air 2S
The underlined section is to allow the drone to optically record the landing area for matching when it comes back.

Precision Landing
The aircraft automatically scans and attempts to match the terrain features below during RTH.
When the current terrain matches the Home Point terrain, the aircraft will land.
A prompt will appear in DJI Fly if the terrain match fails.
Landing Protection is activated during Precision Landing.
The Precision Landing performance is subject to the following conditions:
a. The Home Point must be recorded upon takeoff and must not be changed during flight.
Otherwise, the aircraft will have no record of the Home Point terrain features.
b. During takeoff, the aircraft must ascend at least 7 m before flying horizontally.
c. The Home Point terrain features must remain largely unchanged.
d. The terrain features of the Home Point must be sufficiently distinctive.
Terrain such as snow-covered areas are not suitable.e. The lighting conditions must not be too light or too dark.

The following actions are available during Precision Landing:
a. Press the throttle stick down to accelerate landing.
b. Move the control sticks in any direction to stop Precision Landing.
The aircraft will descend vertically after the control sticks are released.

 

[Forensics_Pilot]

Precision Landing would have worked with any firmware version, not just the most recent.

That was understood regarding the precision landing working with previous firmware versions; no problem there. I was simply confirming that precision landing works with the latest release and it was implied that there was another reason that GMAN007 was having his reported problem of landing accuracy following his most recent firmware download.

 

[Lets Fly]

. The Home Point must be recorded upon takeoff and must not be changed during flight.
Otherwise, the aircraft will have no record of the Home Point terrain features.

And that's the secret. As long as I heard her say Home point recorded check it on the map, my M2Z comes down within inches of the takeoff point. Although I prefer flying it in, I will sometimes hit RTH just to check that its working correctly.

 

[offtheback]

And that's the secret. As long as I heard her say Home point recorded check it on the map, my M2Z comes down within inches of the takeoff point. Although I prefer flying it in, I will sometimes hit RTH just to check that its working correctly.

Sometimes I do it just to say wow!

 

[offtheback]

Here's the Precision Landing section of the manual for the Air 2S
The underlined section is to allow the drone to optically record the landing area for matching when it comes back.

Precision Landing
The aircraft automatically scans and attempts to match the terrain features below during RTH.
When the current terrain matches the Home Point terrain, the aircraft will land.
A prompt will appear in DJI Fly if the terrain match fails.
Landing Protection is activated during Precision Landing.
The Precision Landing performance is subject to the following conditions:
a. The Home Point must be recorded upon takeoff and must not be changed during flight.
Otherwise, the aircraft will have no record of the Home Point terrain features.
b. During takeoff, the aircraft must ascend at least 7 m before flying horizontally.
c. The Home Point terrain features must remain largely unchanged.
d. The terrain features of the Home Point must be sufficiently distinctive.
Terrain such as snow-covered areas are not suitable.e. The lighting conditions must not be too light or too dark.

The following actions are available during Precision Landing:
a. Press the throttle stick down to accelerate landing.
b. Move the control sticks in any direction to stop Precision Landing.
The aircraft will descend vertically after the control sticks are released.

What instrument on the drone scans the landscape?

 

[Meta4]

And that's the secret. As long as I heard her say Home point recorded check it on the map, my M2Z comes down within inches of the takeoff point.

It's not.
Homepoint is recorded refers to the GPS location being recorded.
That will only get you back within a few feet.
For Precision Landing to work, during takeoff, the aircraft must ascend at least 7 m before flying horizontally, and the other points from the manual highlighted in post #10 have to be fulfilled.

 

[Meta4]

What instrument on the drone scans the landscape?

The manual doesn't say.

 

[offtheback]

The manual doesn't say.

At 1st I assumed without evidence thst the camera needed to be pointed down to take a photo of the landing area/pad but that seems too simple.I'll wait while your take yours apart to discover the answer.I feel you may be curious?

 

[Meta4]

At 1st I assumed without evidence thst the camera needed to be pointed down to take a photo of the landing area/pad but that seems too simple.I'll wait while your take yours apart to discover the answer.I feel you may be curious?

It will be either the main camera or the VPS sensors.
It should be pretty simple to see if yours wants to point the camera down as you launch.

 

[Cymruflyer]

I just had my first case of auto landing last week. I always lift off and let it sit there several seconds and the voice message always says... the home point has been updated, please check it on the map. Then I climb up and then go off somewhere.

Last week I needed to quickly take a look from above to see where the best place would be to be off over a lake and come back and circle around as I would be descending and then come through a section in the trees to a point on the ground.

When I lifted off, all was well and the voice message came on about home point update, but I noticed I only had ten percent battery left on the SC, though M2P had a full charge battery fitted. Since the SC battery is always plenty of charge from full for several drone batteries, I felt I had plenty left, to do the possibly minute or two or three, of checking from above that I needed to do and get back on the ground before I would have no power left in the SC.

I have the latest version of all software loaded, by the way. Well within about a minute or so as I was out over the lake, the message showed that I only had 5% left now, which seems to be going quicker than I thought it would. I decided to bring it back rather than try to fly the track I was hoping to fly, to try out my idea, but suddenly the SC started flashing and beeping and then the screen went black.

I quickly tried to turn it back on, to no avail, so I tried to just fly back with the sticks, as I watched the drone, which was just a few hundred feet away and about 60-80 feet high. The sticks did not seem to be working, I assumed everything must have shut down. This is the first time such a thing has ever happened to me in about 4 years of flying.

As I'm watching the M2P helplessly, I see it slowly rotate away from me and start to fly out into the lake and disappear behind a line of tall trees. Now panic set in but there was nothing I could do. I thought I was watching one of those fly away events I had often read about and was preparing myself to never see the drone again. Suddenly I hear it flying back to me and see it come over the tree line again and then hang there and do a little rotating and then it flies away maybe ten or twenty feet and turns again and comes back and then begins to start to land.

It slowly came down and hovered for a few seconds over the picnic table I took off from and gently landed, within an inch or so of where it took off. It didn't even get a leg to fall between the table top sections of wood, which I thought may happen and I would loose a prop or two. Nope, nothing, it landed itself perfectly, all by itself. What an amazing piece of machinery, I thought to myself and picked it up and kissed it. Then quickly looked around to see if anyone was watching. Luckily, I was still all alone.

So, I made a note to self to never again fly without at least 50% on the SC and it was a lesson well learned. As Meta4 has suggested, I believe it was so accurate because of the photo it takes of the take off point, about three feet up when it initially lifts off. From what I understand, it takes a photo through the downward sensor on lift off and hover and then turns it into algorithms and enters that into its location brain and uses that to find its accurate way home to the same spot, in the event of a lost signal. What ever it does it is AMAZING to me.

 

[offtheback]

I just had my first case of auto landing last week. I always lift off and let it sit there several seconds and the voice message always says... the home point has been updated, please check it on the map. Then I climb up and then go off somewhere.

Last week I needed to quickly take a look from above to see where the best place would be to be off over a lake and come back and circle around as I would be descending and then come through a section in the trees to a point on the ground.

When I lifted off, all was well and the voice message came on about home point update, but I noticed I only had ten percent battery left on the SC, though M2P had a full charge battery fitted. Since the SC battery is always plenty of charge from full for several drone batteries, I felt I had plenty left, to do the possibly minute or two or three, of checking from above that I needed to do and get back on the ground before I would have no power left in the SC.

I have the latest version of all software loaded, by the way. Well within about a minute or so as I was out over the lake, the message showed that I only had 5% left now, which seems to be going quicker than I thought it would. I decided to bring it back rather than try to fly the track I was hoping to fly, to try out my idea, but suddenly the SC started flashing and beeping and then the screen went black.

I quickly tried to turn it back on, to no avail, so I tried to just fly back with the sticks, as I watched the drone, which was just a few hundred feet away and about 60-80 feet high. The sticks did not seem to be working, I assumed everything must have shut down. This is the first time such a thing has ever happened to me in about 4 years of flying.

As I'm watching the M2P helplessly, I see it slowly rotate away from me and start to fly out into the lake and disappear behind a line of tall trees. Now panic set in but there was nothing I could do. I thought I was watching one of those fly away events I had often read about and was preparing myself to never see the drone again. Suddenly I hear it flying back to me and see it come over the tree line again and then hang there and do a little rotating and then it flies away maybe ten or twenty feet and turns again and comes back and then begins to start to land.

It slowly came down and hovered for a few seconds over the picnic table I took off from and gently landed, within an inch or so of where it took off. It didn't even get a leg to fall between the table top sections of wood, which I thought may happen and I would loose a prop or two. Nope, nothing, it landed itself perfectly, all by itself. What an amazing piece of machinery, I thought to myself and picked it up and kissed it. Then quickly looked around to see if anyone was watching. Luckily, I was still all alone.

So, I made a note to self to never again fly without at least 50% on the SC and it was a lesson well learned. As Meta4 has suggested, I believe it was so accurate because of the photo it takes of the take off point, about three feet up when it initially lifts off. From what I understand, it takes a photo through the downward sensor on lift off and hover and then turns it into algorithms and enters that into its location brain and uses that to find its accurate way home to the same spot, in the event of a lost signal. What ever it does it is AMAZING to me.

Nor sure if it's possible on the SC but I have the std controller and a Crystal Sky and velcroed a phone charger battery that plugs into the side of the controller.I can fly 10+batteries worth easily.About $20.