RTH

[Music One]

I was able to briefly take my new M2P for its first test flight yesterday. Only really to check it started up ok and check out the RTH. The homepoint was updated and all checked out on the map and I manually took off, rising to a height of about 10ft and waited a minute before flying off a little distance. I then selected RTH on the controller. It returned ok but was off the mark by about 6/7ft. I had the latest software in it. I then took off with the auto take off. I noticed it told me the drone would rise to 3.9ft. It did and then a message came up saying something like homepoint recorded. I flew off again. Then selected RTH off the screen. The drone returned and was spot on the mark. Had to leave it there yesterday and at the moment today its blowing a gale and raining. I will try manual take off again and only rise 3/4ft and wait to see if that makes any difference. Anyone else had a similar occurence.

 

[Meta4]

I was able to briefly take my new M2P for its first test flight yesterday. Only really to check it started up ok and check out the RTH. The homepoint was updated and all checked out on the map and I manually took off, rising to a height of about 10ft and waited a minute before flying off a little distance. I then selected RTH on the controller. It returned ok but was off the mark by about 6/7ft. I had the latest software in it. I then took off with the auto take off. I noticed it told me the drone would rise to 3.9ft. It did and then a message came up saying something like homepoint recorded. I flew off again. Then selected RTH off the screen. The drone returned and was spot on the mark. Had to leave it there yesterday and at the moment today its blowing a gale and raining. I will try manual take off again and only rise 3/4ft and wait to see if that makes any difference. Anyone else had a similar occurence.

Your drone can use just GPS for RTH autolanding and it's accuracy will be variable within the specs of GPS - it will usually be within 6-7 feet but can sometimes be even more.
The drone can also use its precision Landing feature to gat accuracy within a few inches.
Read about Precision Landing in the manual to find out how to use that if you want pinpoint autolanding accuracy.

 

[FoxhallGH]

To get accurate RTH, you need to remember that the Mavic uses its downward-facing cameras to identify the RTH landing area. If you are taking off from an area of just grass, or just tarmac, with no distinctive features, then that makes it difficult for the Mavic to tell where it should come down. If you use a distinctive pop-up landing disc then that helps immensely! The other thing that helps is to ensure that Go4 is telling you that you have a good (green strip) GPS connection before you lift off. Then once you have lifted, don't touch any controls other than the up-stick to take the Mavic [at a reasonable rate] up to 10 metres (30 ft.). Once that's done, the Mavic has a good 'picture' of where it's at, and you can go fly ...
From your description, it does sound like the first flight had not got a good GPS lock prior to take-off [??] - while subsequent flights and RTH landings did have that GPS accuracy.

 

[Music One]

Thanks for the info. I was taking off from a landing matt. Will duly recheck manual take off lock as suggested.

 

[Deleted member 94047]

Not an M2P flyer (I fly the MA) and not a frequent user of the RTH function. But the few times I have used RTH, I have noticed that precision landing kicks in the final stages of the RTH (a message appears on screen informing you of this) even when I had taken off manually. As a result, I had the impression that precision landing was enabled by default as long as your takeoff met two conditions - (1) you takeoff and climb straight up slowly to a height of about 6m (2) you let the AC hover there for a few seconds. Now a comparison of precision landing accuracy after an auto takeoff with the precision landing box ticked and after a manual takeoff meeting the above two requirements would be interesting.

Edit: I just converted the 10ft into meters (sorry I don't understand feet) and that is about 3meters. I think that is too low for the precision landing requirement. Again, I don't know about the M2P, but that feature on the MA requires the AC to climb straight up to a height of 6 meters at takeoff. I don't imagine it would be different for the M2P

 

[RonW]

I have a Mavic Pro and for precision landing the drone needs to ascend approx 10mts(34ft) and hover a few secs to allow a picture of landing area to be taken. The RTH lands it within a couple of inches of take off point in, providing as has been stated, the take off point is clearly contrasted against surrounding area, be it a landing mat or a gravel patch by grass,etc.
I've also found that without precision landing energised, the ac returns to within about a foot or so of take off. GPS acquision is important for all RTH modes, as stated earlier. One important point to remember is to not set RTH height too high and be aware of windage, etc.

 

[Music One]

Thanks for all the info. Ive flown my MA for nearly about 9 months now and hardly ever use the RTH as I like flying manually. All the neccesary settings are in place though in the event. On the time times I have taken off either auto or manual and used the RTH, both have always came back and landed either on, or two legs on /off or within inches of the matt. And I do ascend slowly to around the 12ft mark and wait. I was just curious how the M2P ascends only to a couple of feet and RTH worked spot on. I will be aware more now about double checking the gps lock with manual take off.

 

[25Vettes]

The best thing to do is read the manual:

Precision Landing
The Mavic 2 Pro/Zoom automatically scans and attempts to match the terrain features underneath during Return to Home. When the current terrain matches Home Point terrain, the Mavic 2 Pro/Zoom will start landing. The DJI GO 4 app will show a terrain feature mismatch prompt if matching fails.
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’s terrain features.
b. During takeoff the aircraft must ascend vertically 7 m before moving horizontally.
c. The Home Point terrain features must remain largely unchanged.
d. The Home Point terrain features must be sufficiently distinctive.
e. The lighting conditions must not be too light or too dark.
The following actions are available during Precision Landing:
a. Throttle down to accelerate landing.
b. Move the control sticks in any other direction to stop Precision Landing. The Mavic 2 Pro/ Zoom will descend vertically after the control sticks are released.

 

[Music One]

Again thanks for that info. I must have missed that when I checked. W

 

[Music One]

Message went to quick again. On the the b part about stopping the precision landing. I guessing from that that there is still no manual control over its continuing path.

 

[new2mavic]

You should be able to see a message saying that the drone is doing precision landing and the drone subsequently trying to locate the take off point. In this flight the take off point is the corner of the white markings of the football field :

 

[Bobvt]

To get accurate RTH, you need to remember that the Mavic uses its downward-facing cameras to identify the RTH landing area. If you are taking off from an area of just grass, or just tarmac, with no distinctive features, then that makes it difficult for the Mavic to tell where it should come down. If you use a distinctive pop-up landing disc then that helps immensely! The other thing that helps is to ensure that Go4 is telling you that you have a good (green strip) GPS connection before you lift off. Then once you have lifted, don't touch any controls other than the up-stick to take the Mavic [at a reasonable rate] up to 10 to 15 ft. Once that's done, the Mavic has a good 'picture' of where it's at, and you can go fly ...
From your description, it does sound like the first flight had not got a good GPS lock prior to take-off [??] - while subsequent flights and RTH landings did have that GPS accuracy.

Just remember to set rth height higher than the highest obstacle near you or in its path of rth.

 

[AMann]

As 25Vettes pointed out, precision landing always sticks it for me almost perfectly when I go straight up above my pad to 7m (23ft), wait for the precision landing confirmation and then go flying. Use a high contrast pad that does not match the ground, and don’t expect it to work very well if there are shadows or if you are flying close to dawn or dusk.

 

[Fred Garvin]

I have a landing pad in my backyard built from 16” patio pavers and a 32” pad mounted to a 3/4” plywood circle. Whenever I fly from my backyard, I let the M2P hover above it at 20’ until I get the precision message.

I don’t use RTH as I prefer to fly my aircraft at all times, but as a safety measure I make sure it’s setup, just in case. I have tested RTH and it works perfectly, landing better than I do sometimes.