Litchi Seems Inconsistent

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Today I flew a standard mission but forgot to turn on the video. The drone (P4) flew well. This was about noon. I charged a battery and flew the mission again about 2:30. This time it "encountered" a large tree during the mission. Several questions: Could the steepness of my driveway take-off point be an issue? When the drone "saw" the tree it stopped. What are my options when the drone is hovering there? I thought that the drone would automatically see the tree and go over it, why didn't it? Thanks in advance to your insightful replies.
 
If you're using Litichi mission hub, uncheck "private" and send me the link to the mission. I';ll gladly take a look at it
 
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With about 1,600 miles of Litchi autopilot missions under my belt, I have taken the liberty of awarding myself an honorary doctorate degree in Pure and Applied Litchiology. Donning my conical thinking cap to ruminate over the predicament you have described, my initial hunch is that you may have accidentally set a waypoint altitude lower than the obstacle in the flight path.

Plotting complex 60-waypoint missions lasting 22 minutes, I have on occasion entered negative altitude waypoint altitudes that I only caught during pre-flight cross-checking during which I closely scrutinized each waypoint in turn. If the mission you flew was not altered in any way, yet the tree still got in the way, it is also possible that the margin of altitude error you allowed was too slim, meaning that you programmed the drone to fly a tad too low above the tree canopy in your area.

To illustrate Litchi's altitude inaccuracy, the altitude callouts at my landing point have varied from 10 feet AGL to minus five feet BGL (Below round Level) ha ha. With that alarming variability in mind, I always make sure to allow at least a 20-foot clearance above all trees along my intended flight paths. May the force be with you, and may your drone never encounter a flying Tic-Tac or triangular TR-3B.
 
How do I do that. I see the share widget but how do I send it to you?
From the Litchi mission hub, click "Missions" then "open" a window will open that shows your saved missions. Uncheck "private" to the mission you're talking about.

1625063048795.png
 
What are you wanting to focus on? The house or the field? At what waypoint did your drone "catch a tree"?
As far as I can see, there is no reason for that to have to happen. The lowest wp is number 1 at 52 ft. all others are 101. Unless there is a reason for starting out so low, you can change #1 to match the others
 
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The tree line between the 3rd and 4th waypoints. There is a tree about half-way that caused the drone to stop on my last mission run. But the drone flew over the tree on the same mission an hour or 2 earlier.
 
Today I flew a standard mission but forgot to turn on the video. The drone (P4) flew well. This was about noon. I charged a battery and flew the mission again about 2:30. This time it "encountered" a large tree during the mission. Several questions: Could the steepness of my driveway take-off point be an issue? When the drone "saw" the tree it stopped. What are my options when the drone is hovering there? I thought that the drone would automatically see the tree and go over it, why didn't it? Thanks in advance to your insightful replies.

It may be that the quads altimeter wasnt zeroed, the older P range had issues, The only way to know for certain is to pull the Litchi flight log and see what initial figure is shown for starting height, but then it may have affected the other WP's.

Either way I can get a better idea using the flight log as opposed to the Litchi mission plan
 
Sorry but I don't know how to access the flight logs. Please advise.
Easiest way is to use airdata website
Quick guide here

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The tree line between the 3rd and 4th waypoints. There is a tree about half-way that caused the drone to stop on my last mission run. But the drone flew over the tree on the same mission an hour or 2 earlier.
Do you know how close the drone was to the tree first time?
It's not Litchi that's inconsistent, GPS (for horizontal position) and the barometric sensor for vertical position) are not consistent.
You always need a comfortable safety margin when flying waypoints near obstacles
 
At WP3 grondlevel is 12m (40ft) higher than at WP1.
So at WP3 your drone will be flying 12m lower to the ground.
Also there's a 4m height difference between the start and end of your driveway.

The heights you set at all waypoints are relative to the take-off point, NOT WP1 !!

If you want to set your heights at (all) waypoints relative to ground:
1. In Settings check "Use Online Elevation".
2. In (all) waypoint settings check "Above Ground" directly under "Altitude"

The P4P will fly over obstacles when the obstacle is big and DENSE enough.
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I strongly suggest reading the online Litchi-Manual.
 

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The same mission conducted 3 times. The first two cleared the tree. The third one did not. Here is a link to the videos on YouTube
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How do I upload the CSV Flight Logs?
 
The same mission conducted 3 times. The first two cleared the tree. The third one did not. Here is a link to the videos on YouTube
Because the drone has a very wideangle lens, it was closer to the trees than the video suggests.
The tree at 0:53 is much too close for safety with waypoints.
Another at 1:32 isn't much better.
Because of inconsistency in horizontal and vertical positioning, you need a bigger safety margin when flying waypoints.

I'm concerned about your earlier question: >> Could the steepness of my driveway take-off point be an issue?
Are you asking about the angle of the driveway surface, or have you launched from different levels on the driveway?
Launching from different levels will affect the height of your waypoints, because they are relative to the launch point.
Wherever you launch from equals zero ft.
 
How do I upload the CSV Flight Logs?
Asuming you are using AirData for your flightlogs:
Click the share-button in the right-upper corner, a new window appears, uncheck personal data, then click on "Create a unique sharing link" and post it here. (see picture).
However it won't tell anything about the cause of the crash.

At WP3 the drone will actually fly at the height you set in the mission=100ft minus 40ft (groundlevel height difference between WP1 and WP3) plus or minus groundlevel height difference between WP1 and the takeoff point.
All of this is pure theoretical, you have to take in account (error) margins in the given online elevations, GPS-data & barometric height-data from the drone, like Meta4 allready wrote.
 

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