Litchi's Smart Return Home option in waypoint mode

[TaiTony]

Today I almost crash my Mavic Air when run the mission. I open the smart return home option in the setting, but when the smart return home will be trigger ?

This mission is run couple time, this area is limited to 60 meters but can apply unlock from DJI to 180 meters because nearby airport altitude is 200 meter higher than downtown. That is the issue of DJI and I have request DJI to answer. I have unlocked the MA to 180 meters but Litchi can not go up to WP2 that I set to 80 meters. But I still fly other mission yesterday over 100 meters without problem in same areas.

When Litchi mission can not reach the WP2 height (80 meters) and than cancel the mission automatically and run Smart Return Home and almost crash to high building. When I hear the beep from phone, I use manual control to rotate the aircraft. What the difference of RTH(when manual control and loss connection) and Smart Return Home in Waypoint Mode. Can any one advise these two type of RTH ? In mission control, I set none for finish action instead of RTH. But why:

1. Why cancel the mission automatically ?
2. Why trigger Smart Return Home ?

 

[slup]

Can you upload the Litchi log file to --> to either PhantomHelp or AirData and post the link back here.

On Android devices the Litchi CSV logs are in LitchiApp » flightlogs.
Litchi also creates a standard DJI TXT log, which for some reason it stores in a subdirectory in the DJI app directory, DJI » com.aryuthere.visionplus » FlightRecord.

On iOS devices, the Litchi CSV logs are in Litchi » Documents » flightlogs, and the DJI TXT logs are in Litchi » Documents » SDK_logs » FlightRecord.

Either one of them will do ...

Could be interesting to see if something is shown there that reveals what happened.

 

[RodPad]

I would like to see the mission, can you share it on the hub.

Rod

 

[Deleted member 94047]

I did a little googling on this same question because I also want to know if it is possible to use DJI's Geo Zone unlocks with Litchi. Looks like you may need to star with GO4, upload the unlock code to the AC, and switch to Litchi once the geo zone is unlocked and the AC is in the air. Have a look at this thread

Question about DJI unlock when paired with Litchi hub app

So if I got access to unlock a radius in a blue auth zone for the DJI and apply that license to my aircraft via the DJI app, does it then allow me to swap the app to use Litchi and fly a preprogrammed waypoint mission within the parameters of that radius or no? Is the authorization dependant on...

mavicpilots.com

 

[TaiTony]

Can you upload the Litchi log file to --> to either PhantomHelp or AirData and post the link back here.

On Android devices the Litchi CSV logs are in LitchiApp » flightlogs.
Litchi also creates a standard DJI TXT log, which for some reason it stores in a subdirectory in the DJI app directory, DJI » com.aryuthere.visionplus » FlightRecord.

On iOS devices, the Litchi CSV logs are in Litchi » Documents » flightlogs, and the DJI TXT logs are in Litchi » Documents » SDK_logs » FlightRecord.

Either one of them will do ...

Could be interesting to see if something is shown there that reveals what happened.

From Air Data show the reason to trigger Smart Return Home due to lack of enough numbers of GPS. But it take off at 10 GPS but become 6 when it reach 50 meters. I send messenger to Litchi support and they told me the Smart Return Home is due to DJI firmware not Litchi but you can turn off the Smart Return Home.

The numbers of GPS become lower than take off may related to the high buildings(most higher than 120~150 meters) nearby the take off point.

In same day morning I fly in other area over 100 meters is OK due to the enough GPS.

For manual control for same issue and avoid the trigger of Smart Return Home, now I set this option to OFF in the setting of aircraft in Litchi.

I attach the reply from Litchi and two Air Data route.

So now I understand the issue and thank for your comments.

 

[TaiTony]

I did a little googling on this same question because I also want to know if it is possible to use DJI's Geo Zone unlocks with Litchi. Looks like you may need to star with GO4, upload the unlock code to the AC, and switch to Litchi once the geo zone is unlocked and the AC is in the air. Have a look at this thread

Question about DJI unlock when paired with Litchi hub app

So if I got access to unlock a radius in a blue auth zone for the DJI and apply that license to my aircraft via the DJI app, does it then allow me to swap the app to use Litchi and fly a preprogrammed waypoint mission within the parameters of that radius or no? Is the authorization dependant on...

mavicpilots.com

Yes, I use GO 4 to upload the unlock certification to Mavic Air and than you can use Litchi to fly in GEO zone. But you must turn off the unlock when you are outside the unlock range, otherwise DJI will not allow you to take off.

 

[Deleted member 94047]

But you must turn off the unlock when you are outside the unlock range

That is great info, many thanks!

 

[slup]

From Air Data show the reason to trigger Smart Return Home due to lack of enough numbers of GPS. But it take off at 10 GPS but become 6 when it reach 50 meters. I send messenger to Litchi support and they told me the Smart Return Home is due to DJI firmware not Litchi but you can turn off the Smart Return Home.

The numbers of GPS become lower than take off may related to the high buildings(most higher than 120~150 meters) nearby the take off point.

In same day morning I fly in other area over 100 meters is OK due to the enough GPS.

For manual control for same issue and avoid the trigger of Smart Return Home, now I set this option to OFF in the setting of aircraft in Litchi.

I attach the reply from Litchi and two Air Data route.

So now I understand the issue and thank for your comments.

If you want us to have a closer look & share the reasons for the event for educational purposes please share the link to Airdata ...

Push this button in the Airdata flight log & paste in the link here.

 

[Deleted member 94047]

I have never heard of a drop in GPS signal triggering RTH - I thought the AC would switch to vision or Atti. In fact, if GPS signal is the issue, how would it be able to travel back to the home point? Or is this a Litchi thing since I suppose a way point mission would require the AC to have GPS data to be able to complete the mission?

 

[TaiTony]

If you want us to have a closer look & share the reasons for the event for educational purposes please share the link to Airdata ...

Push this button in the Airdata flight log & paste in the link here.

View attachment 89988

Sorry for late reply. This is the air data link for that flight.
Smart Return Home issue

 

[TaiTony]

I have never heard of a drop in GPS signal triggering RTH - I thought the AC would switch to vision or Atti. In fact, if GPS signal is the issue, how would it be able to travel back to the home point? Or is this a Litchi thing since I suppose a way point mission would require the AC to have GPS data to be able to complete the mission?

From data log the Smart Return Home change from waypoint mode to P-GPS mode. No issue of ATTI.