Programming missions with varying terrain

[Brojon]

So rather than risk my machine I'm hoping someone can detail some Litchi behaviors for me.
I'll use big round numbers to help focus on the answers and not get hung up on math.

So assume my takeoff point is 500ft above sea level.
I takeoff and rise to 100 feet.
I can assume this 100 feet is above the reference takeoff point.
I fly 2000 feet and the terrain drops 200 feet.
Is the height still 100 feet relative to the takeoff point? This would mean I'm flying 300 feet above the destination?
This has import because I go to where I'm going to be flying and measure the height of objects I'd rather not collide with.
At the waypoint if I set the height different will it still be relative to the takeoff point? The point of teh question being I need to know the relative terrain height difference to set height to something safe at that point.
When on a mission is collision avoidance active?
If return to home is set as mission end action will it ascend immediately to the RTH preset height or will it ascend while returning?

Thanks!

 

[Brojon]

Just as an FYI I discovered:
a - Height is always relative to takeoff point unless
b - you use teh batch edit to change waypoints relative to ground at which point it uses Google terrain data to set the height above the ground level as Google reports it at that waypoint.
I assume that as per other height changes Litchi sets a slope to smoothly traverse the height change.
Trying to figure a way to verify this without crashing drone.

 

[Racenviper]

Create your mission in Litchi, change your "Unit" settings to metric and export to a CSV file. Open the CSV file in a "TEXT EDITING PROGRAM" like "Notepad" not Wordpad or Microsoft Word. Formatting will destroy the CSV file. Copy the first waypoint line and past it so you now have two waypoint that are the same. Change the "Alt" of the copy to zero and save.

Use this site: Convert Litchi .csv file to .kml with elevation to convert the CSV file to a KML file. It can then be imported into Google Earth. Same process I used to do this: http://mavicpilots.com/attachments/flsc-litchi-chart-curve-2-poi-jpg.15460/

 

[jimmybbq]

Create your mission in Litchi, change your "Unit" settings to metric and export to a CSV file. Open the CSV file in a "TEXT EDITING PROGRAM" like "Notepad" not Wordpad or Microsoft Word. Formatting will destroy the CSV file. Copy the first waypoint line and past it so you now have two waypoint that are the same. Change the "Alt" of the copy to zero and save.

Use this site: Convert Litchi .csv file to .kml with elevation to convert the CSV file to a KML file. It can then be imported into Google Earth. Same process I used to do this: http://mavicpilots.com/attachments/flsc-litchi-chart-curve-2-poi-jpg.15460/

Wouldn't it just be easier to program on the Litchi website, then open the mission in Litchi, batch edit waypoints to be AGL, then save? Maybe I'm not understanding what you're trying to accomplish. Also, from what I've read, collision avoidance is not active during a mission.

Why can we not select AGL on the mission planner website?

 

[cirrusly]

Wouldn't it just be easier to program on the Litchi website, then open the mission in Litchi, batch edit waypoints to be AGL, then save? Maybe I'm not understanding what you're trying to accomplish. Also, from what I've read, collision avoidance is not active during a mission.

Why can we not select AGL on the mission planner website?

Unfortunately altitudes relative to AGL aren't supported yet on the website. However, it's not a big deal to create the mission on the website, download it on your device, then change the elevations to be relative to ground. Compared to any other options out there that's by far the easiest. Hopefully in a future update we'll be able to do so directly from the website interface.

 

[Racenviper]

Maybe you want to do a mission like this:


Because Litichi only works in a flat world, you could program this:


Thinking you were getting this:


Exporting out the mission to a CSV and converting it to a KML, then viewing in google earth will let you tweak your altitude values.