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[mereflyer]

Anyone know what to do when a Mavic Pro using Litchi app, whether flying FPV or Waypoint flights, persistently misses the landing pad on auto RTH by at least 5 or 6 metres and has to be manually landed because of the error?

Anyone else having this problem?

BTW I have re calibrated everything several times as suggested by other learned operators on these Forums.
Any suggestions very much appreciated!

 

[Former Member]

Anyone know what to do when a Mavic Pro using Litchi app, whether flying FPV or Waypoint flights, persistently misses the landing pad on auto RTH by at least 5 or 6 metres and has to be manually landed because of the error?

Anyone else having this problem?

BTW I have re calibrated everything several times as suggested by other learned operators on these Forums.
Any suggestions very much appreciated!

Does it also land that far away when you use DJI Go 4 precision takeoff?

5 to 6 meters is alot. I rarely find a drone that lands exactly, or within 1 foot of where it took off from. But 5-6 meters means that something is wrong with your sensors.Have you tried wiping off your bottom plate or check for dirt or debris?

 

[mereflyer]

Does it also land that far away when you use DJI Go 4 precision takeoff?

5 to 6 meters is alot. I rarely find a drone that lands exactly, or within 1 foot of where it took off from. But 5-6 meters means that something is wrong with your sensors.Have you tried wiping off your bottom plate or check for dirt or debris?

I have not used DJI Go4 this last many weeks, much happier to use Litchi. Will try Go4 and let you know later.

Yes I have carefully wiped the sensors and tried every thing in the book, still no accuracy. Might be a faulty sensor eh?
Thanks for replying

 

[Former Member]

Might be a faulty sensor eh?

Its possible, but then you would get a sensor error in Litchi.

Check out this web page. Down where it talks about RTH settings.

RTH Settings in DJI GO/4

DJI Guides - DJI Store (United States)

Online shopping for a great selection of at the official DJI Online Store.

store.dji.com

 

[Simmo]

I agree with what Rob says, but has this happened in differant locations?
Is the location in this case open enough for good GPS coverage?

 

[Meta4]

I have not used DJI Go4 this last many weeks, much happier to use Litchi. Will try Go4 and let you now later.

Litchi/DJI Go 4 shouldn't make any difference since the RTH process is part of the drone's firmware and is independent of the app used to fly.
Precision landing is not magic and has a number of limitations that could cause it to fail.
The manual has a listing you should check to see if any apply to your situation.
If you can't track down the issue, try using DJI Go 4 and share your flight data to see if the solution is in the data.

 

[mereflyer]

Litchi/DJI Go 4 shouldn't make any difference since the RTH process is part of the drone's firmware and is independent of the app used to fly.
Precision landing is not magic and has a number of limitations that could cause it to fail.
The manual has a listing you should check to see if any apply to your situation.
If you can't track down the issue, try using DJI Go 4 and share your flight data to see if the solution is in the data.

Thanks for that - Inclement weather prevents further experiment, will get back with update info when next possible.

 

[mereflyer]

Its possible, but then you would get a sensor error in Litchi.

Check out this web page. Down where it talks about RTH settings.

RTH Settings in DJI GO/4

DJI Guides - DJI Store (United States)

Online shopping for a great selection of at the official DJI Online Store.

store.dji.com

Thanks for that Thunder, Yes I am familiar with all of those battery instructions and adhere to those settings and RTH advice.

My MP1 was fairly accurate at landing on the spot for the first 6 months as I remember. Has never had an accident or heavy landing.

Seems to coincide with or about the time I changed over to Litchi. about a similar 6 months ago.

Has not really been a huge problem as I usually hand catch the landings.

However it has become a niggling point and I would like to fix it - if not too much trouble!

When the time and weather are suitable I will fly again using DJI Go4 app for control and let you know the outcome.

Other than that I still get huge enjoyment flying and enjoy the excellent photo and video capabilities. Is still very accurate at finding and following waypoints and have a 1TB HDD devoted only to the many video files taken from MP1.

 

[mereflyer]

I agree with what Rob says, but has this happened in differant locations?
Is the location in this case open enough for good GPS coverage?

Thanks Simmo,
Yes I have had the same lack of landing accuracy at about 7 or 8 different spots - most well clear of obstacles etc -- (Just had a thought - maybe its allergic to me!!!)

 

[Steve S in Arizona]

I am new to this and fly a Mavic Air from a small patio adjacent to my house. The DJI go 4 app consistently shows my home point accurately on the map. Litchi puts it about 20 feet away on the roof of my house. I have allowed the go 4 app to complete a RTH landing, but have been afraid to allow litchi to do so. Go 4 lands within a foot or so of the takeoff point. I wonder if there might be a difference in the maps that the apps use.

 

[Simmo]

Litchci and go 4 use the same basic parameters eminating from the same data.... no reason that there should be a differance?

 

[Former Member]

Here are some things I have found.

Yesterday I flew my M2Z a few times using both Litchi and DJIG04. Both apps landed the drone within 1 foot of the home point. Not great, but as @mereflyer does, I always gimbal straight down to see where the crosshairs on the grid line up, and manually adjust the drone if necessary to where I want to pu it down.

At the last DSAR meeting, people were using RTH for landing on dozens of different drones. Very few ended up landing within 1 foot of the home point. Almost everyone was using a landing pad, which should have been a clear enough target for the drone to see.

I was awed a couple of days ago by a customers older Mavic Pro Platinum that I had just finished a repair on, and test flew. Not only did it fly like it was brand new, but that sucker landed closer to the home takeoff point than any other drone I have ever test flown. When it landed, I just grinned and said to myself, "thats what RTH is supposed to do!" It landed closer than all the M2's, Sparks, Airs, and other drones I had ever test flown. Accuracy seems to be a little bit off with RTH on most drones, but it gets you close.

Im wondering if anyone has some advice on what to use on the ground to make to drone land closer to the home point? I have used landing pads, chalk, cardboard, none really help the accuracy of the final landing spot.

 

[Aussie Oldtimer]

Mine makes me recalibrate the compass before every flight. I used to find it annoying

When I first got it, it would sometime bee up to 1m off but now it is always within 200mm. better than any hand held gps I own

 

[Meta4]

When I first got it, it would sometime bee up to 1m off but now it is always within 200mm. better than any hand held gps I own

If it's always within 200mm, it's not using GPS to achieve that.
The GPS in the Mavic is only as accurate as a handheld unit.

 

[Aussie Oldtimer]

If it's always within 200mm, it's not using GPS to achieve that.
The GPS in the Mavic is only as accurate as a handheld unit.

so how does it get so accurate if not gps?

 

[Meta4]

so how does it get so accurate if not gps?

The precision landing system uses optical technology.
It photographs the launch spot from above and matches that to land in the same spot.

 

[mereflyer]

Here are some things I have found.

Yesterday I flew my M2Z a few times using both Litchi and DJIG04. Both apps landed the drone within 1 foot of the home point. Not great, but as @mereflyer does, I always gimbal straight down to see where the crosshairs on the grid line up, and manually adjust the drone if necessary to where I want to pu it down.

At the last DSAR meeting, people were using RTH for landing on dozens of different drones. Very few ended up landing within 1 foot of the home point. Almost everyone was using a landing pad, which should have been a clear enough target for the drone to see.

I was awed a couple of days ago by a customers older Mavic Pro Platinum that I had just finished a repair on, and test flew. Not only did it fly like it was brand new, but that sucker landed closer to the home takeoff point than any other drone I have ever test flown. When it landed, I just grinned and said to myself, "thats what RTH is supposed to do!" It landed closer than all the M2's, Sparks, Airs, and other drones I had ever test flown. Accuracy seems to be a little bit off with RTH on most drones, but it gets you close.

Im wondering if anyone has some advice on what to use on the ground to make to drone land closer to the home point? I have used landing pads, chalk, cardboard, none really help the accuracy of the final landing spot.

Yes Thunder, I find the same as you, have tried many types of landing pads, no real difference noticed.

The main problem of poor landing spot accuracy as I said above, still remains.

Weather still no good here so have not yet tried Go4 again, will do so at next opportunity.

 

[Former Member]

Im going to do some experiments. Maybe a high contrast landing pad.

 

[mereflyer]

Well the weather cleared for a while today, so I tried the Go4 app instead of Litchi and to my surprise the Mavic Pro (RTH)
Landed on the pad within about 200mm of the takeoff.

So what I deduce from this?

The comparison with the Litchi app's inaccuracy had me really starting to think there could be a fault in the Litchi algorithm. Could this be true?

Will try something different - Delete Litchi, purge the cache of my Tab A Tablet and then try a reinstall to see if that makes any difference!

Will this work - Any of you Litchi specialists welcome to chime in with your thoughts or suggestions.

 

[Former Member]

Before you do anything else, maybe try Litchi. See if, after Go 4 was so accurate, if Litchi is more accurate. Some functions of Litchi are translated from DJI Go 4.