Litchi - Google Earth Notes

[dwallersv]

With the new (awesome!!!) Ground-Relative feature built-in Litchi, there is now the reverse problem: How to export a path from Litchi to GE so you can visualize it in 3D, and make changes to avoid obstacles (trees, structures) that are not accounted for by the GIS terrain data.

A fellow member has coded up an online converter that will take a Litchi CSV export and convert it to a suitable KML file that can be opened in GE. It works quite well, although one caveat: You need to add an extra waypoint in Litchi as your first waypoint at ground (altitude 0) level for the converter to calculate the waypoint altitudes correctly for GE.

You can find it here:

Litchi CSV to KML tool

Props to @Member for developing this tool, and also for bagging the handle, "Member"

My procedure now is to create the mission in the Litchi Android app, export from Hub, run through the converter, view in GE. Make any necessary adjustments/additions in the Litchi app while examining the path in GE. Rinse and repeat as necessary.

 

[The Springs]

I prefer planning a path in GE as well and using the Litchi feature to double check .
With GE you can overlay a line or circle and plot your path along it you can also "play "the path and look at the elevation profile as well
I would like to able to overlay say a hexagon or pentagon with a variable radius, put a WP (path points) on each point then add the curves later in Litchi ,the aim being to get a perfect POI circle .

bsartist I think everyone has a brain fade now and then . I still find it counter to my instincts to push a lever forward to go up . I dropped my P3 into a 40 ha wheat crop due to a" brain inversion" .The camera was still on I could see a wheat plant stem with 5 aphids on it .I thought "well that will narrow the search are down considerably !"
If you not giving the chimney trick a go plan a mission around one of those islands on Lake George .Lifes short go for it .

 

[Member]

one caveat: You need to add an extra waypoint in Litchi as your first waypoint at ground (altitude 0) level for the converter to calculate the waypoint altitudes correctly for GE.

Thanks for the plug. A small correction there if I may:

Waypoint mission point altitudes are relative to where you turn on the drone. So if your first point's altitude is 20m, the program assumes it's 20m above ground just below it. Since it doesn't know where you turn on the drone, it can only do one thing: assume you launch the mission from your starting point. So adding an extra point is only necessary if you're launching the drone from elsewhere, and it's a way of telling the program what the relative altitude is relative to.

Short: you don't necessarily have to add an extra point and it definitely doesn't have to be set to altitude 0. The altitude won't matter because you're just setting the coordinates to a point from where the altitude will be used for the relative calculations. It will only change how GE shows the first line but will still calculate the waypoint altitudes correctly.

 

[dwallersv]

Thanks for the followup, @Member... not sure where I got that bit about the 0 altitude waypoint. I went back and checked, and indeed it isn't necessary.

Thanks again for developing, and hosting, this very useful tool.

 

[The Springs]

I do most of my planning on GE and the hub I just find the app even on a 8" tablet too small for my big fingers and not so good eyesight (easy to make mistakes).
So I have a question .When I import a kml file to Litchi Hub from GE it wont let me set curved turns in settings What I mean is you can select curved turns but it does not implement them I have to go from WP to WP and put them in. If I am creating a mission in the hub its not a problem and once the mission is on the app the same might apply (I haven't tried)
Have you come across this ?
I have also fiddled with different speeds between WPs then when you watch the speed as the mission progresses the speed changes appear to be a bit random.
Thanks

 

[dwallersv]

@The Springs, yes, this (and other waypoint settings) is among the reasons I find the workflow in the other direction much more efficient. Another issue is altering the position or altitude of a waypoint after imported to Litchi, and then visualizing that change in GE. Try that one when you import from GE to Litchi, and keep all the settings for each waypoint.

Can't.

If you use the Litchi interface as the primary interface -- where you're creating/locating waypoints and setting their altitude, and other settings -- then export to GE via @Member's converter for visualization and checking in 3D, you preserve all the detailed other mission settings in waypoints et al.

If you don't like the tablet app for the Litchi part, just use Mission Hub. This has been possible for a while for those that knew the secret of @Member's converter Me? I was just excited to be able to do this on the Android app with the new ground-relative altitude feature. I prefer to do it there over the hub, as there are features that are not available on the hub.

 

[Member]

Now if only DJI didn't encrypt the flight logs or if there was a way I could visualize a flight log in Google Earth without uploading everything 'to the cloud'...

 

[dolphindancer]

Altitude... I used GE to define a path to import to MIssion Hub. I have tried clamping the path to ground as well as making it relative to gound at 200' height. After creating a mission for both, specifying a 100' altitude and then exporting them to CSV, I don't see any difference in the altitude displayed. This causes me to believe Litchi ignores the relative to ground height in the path with that option Also...

There are three options in Litchi's batch edit process for Litchi Altitude to refer to: Home, Current or Ground. My understanding is selecting Ground will cause the drone to fly at the specified Litchi Altitude above the Google Earth surface below the mission flight path. So barring obstructions not considered by
GE, seems an easy way to go



Comments and Counsel Appreciated

 

[The Springs]

dwallersv thanks for the diffections to the converter I have used it often now .Thanks Member also.
dolphindancer I have planned many paths on GE "relative to ground ' with only one odd transition to Litchi path
.
I usually set the height to 30-33m which clears most of our trees .I know every part of our farm so I have a good idea of individual tree heights and elevation changes .Our tree cover is only about 10% or less so I generally plot between the trees any way.
I usually don't alter the mission in the field (too easy to make a mistake ) So I prefer using GE

The odd thing I was talking about was a mission that imported to Litchi oddly . I was in a hurry(always a bad idea) and didn't notice that instead of maintaining 33m above the ground it had actually added 10-15 m progressively as it climbed up a 70m rise so this I ended up at 168m instead of about 101m ? I only notice this later .I'm glad it did not subtract it !
I re-imported the same file and got the correct result .Very strange.