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Litchi beginners question / Waypoint missions

Butterfly Copper

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As a complete litchi beginner I have a basic question to the experts in waypoint missions.

I understand that you can plan your waypoint mission at home, upload the result to the app and then have your drone autonomously complete the mission (without even being connected to the drone).

Is this really the way it works? Are the maps exact enough for giving you the desired results? How often do you have to re-adjust and to re-fly the mission before this fits?

What about the height of the flight? How do you calculate this (especially in a hilly area) and aren't you worried about miscalculations and obstacles you simply have not planned or forgot?

I would really be interested how you plan your missions and if you could get some clues how to fly safe here :)
 
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1. The desktop "Mission Hub" syncs automatically to the app. You don't have to do anything except verify that the sync took place.
2. The base-map in Litchi is quite accurate horizontally, within 10 ft. It may be outdated, and not show all current obstacles, however. 'Flying' in Virtual Litchi Mission will avoid many post-flight adjustments to the mission regarding gimbal pitch, yaw, etc.
3. Above-ground elevations for each way-point can be set using Litchi if desired. This does NOT account for tree heights, buildings, wires, etc. and also uses elevation models that may not be completely accurate. Use an appropriate height that has a good margin for error. This is where most of the risk is, especially if flying where you will lose radio contact. My workflow is to first roughly plan the flight path in Google Earth (there are tutorials on how to do this). This will allow you to work in a virtual 3d environment with way-points/paths as opposed to the Mission Hub. Some regions (although not mine) also show 3d renderings of buildings and trees. Import the GE path into Litchi (as a KML) to make further adjustments, then fly with Virtual Litchi Mission.
4. It's best to always have a "loop" mission, with your first way point directly above the takeoff point, and your last point close to the first.
 
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Thanks for the expertise you are sharing here. I will definitely have a look at the Virtual Litchi Mission + the tutorials for Google Earth. Yepp, a loop mission definetely makes sense!
 
I use Litchi exclusively for way points, and also check flights in Virtual Litchi/Google Earth. Am able to 'see' how bird flies and what camera is looking at. I can adjust angles, etc before going to location. I like to keep to minimum of 100 feet as not many trees here above that. I generally find that most of my videos are best from 250ft, this gives a good view of subjects. Here's a tip for you, try to keep gimbal angle about - 20degrees interpolated when flying missions, when not actually looking at Poi's. This gives a nice balance of sky and land and better exposure. Practise is your friend.
 
Another tip if using iPad: plan mission on Mission Hub, view results on VLM. Power on ipad, make sure new mission is auto downloaded to ipad Litchi, open new mission on ipad to show mission location, press power button once to blank screen of ipad DO NOT SWITCH POWER OFF COMPLETELY. When on location, press power button once more and hey presto, your mission and map is available. Use way point or fpv function and fly your bird. Ipads do not save maps when shut down, hence reason to only blank screen before leaving home.
Hope this helps.
 
Make sure you understand how the ground altitude reference is being handled On your mission.
 
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I've done lots of Litchi Missions via the mission hub. I generally go the location (before flying the mission), and manually fly to any of the waypoints I'm not sure about (elevation-wise), and make note of where I can safely fly. I generally add at least 10' to the waypoints to make sure it is far enough away (like trees). Remember that trees grow pretty fast, and you aren't always sure when Google Earth took the reference photo. Once you safely fly the mission a couple of times, you can go in later and "tighten" up the waypoints if you like. Have fun!

Oh, make sure you know how to abort a mission if you see your aircraft get too close to something - on my Mavic Pro, I just switch it to SPORTS mode, and that cancels the mission. Then I can fly it back manually. You can also push the PAUSE button on the RC, and it will pause the mission. If you are flying a Phantom, you switch the mode switch out of F mode, and that cancels the mission.
 
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I've done lots of Litchi Missions via the mission hub. I generally go the location (before flying the mission), and manually fly to any of the waypoints I'm not sure about (elevation-wise), and make note of where I can safely fly. I generally add at least 10' to the waypoints to make sure it is far enough away (like trees). Remember that trees grow pretty fast, and you aren't always sure when Google Earth took the reference photo. Once you safely fly the mission a couple of times, you can go in later and "tighten" up the waypoints if you like. Have fun!
This is something I immediately understand: do a manual flight first and plan in detail afterwards. Thanks for explicitly pointing this out as I somehow had the impression that the "experts" are planning on the map and are confident enough to fly the wildest missions completely autonomously.
 
This is something I immediately understand: do a manual flight first and plan in detail afterwards. Thanks for explicitly pointing this out as I somehow had the impression that the "experts" are planning on the map and are confident enough to fly the wildest missions completely autonomously.
Your impression was not incorrect. It's entirely feasible to plan out-of-contact missions on your PC and fly them without visiting the site first. Obviously there is risk in doing this, and the risk will vary with the site you plan to fly. I've done it that way exclusively, but not without at least some fore-knowledge of the actual site conditions and obstacles. I've never manually flown a site before a mission, most times it is not practical. My longer autonomous flights are over heavily forested and remote areas and several have been longer than 4 miles over terrain with significant elevation changes. I have a good idea of when radio will be lost and I minimize the amount of time as best I can. It's a risk vs. reward scenario. Plan and fly your original mission at greater relative height than you think you need. It's a simple process to lower the path and fly a second time. As I mentioned above, Virtual Litchi Mission is invaluable for pre-flight planning.
 
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Make sure you understand how the ground altitude reference is being handled On your mission.
I understand that the altitude parameter in the app is relative to your position. On the other hand the Mission Hub takes the elevation of the area in account.
 
When you plan to fly over uneven terrains, an other advantage of flying first a VLM virtual mission, which was not mentionned above is to look at the visual basin of your drone at waypoints where the connexion can be lost because of the "shadow" of hills, trees or whatever. In Google Earth, just click right on the suspected waypoints and click on "Viewshed" in the menu. This will color in green the areas where your drone can be "viewed" by your RC and, hence, the areas where your RC can transmit gimbal and speed commands to the drone (these commands are not stored in the drone memory as is the rest of the mission data). For example in the image below, if I stand close to waypoint 1 (in this mission, I had no alternative), VLOS is maintained at waypoint 7 if I fly at an altitude of 210m (first image) but not if I fly only at 90m (second image). However, 90m would be largely enough to clear all obstacles.
 

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Thanks a lot for your tips and advice regarding litchi waypoints! I am sure that nothing that I write here is any news for experienced pilots, but maybe some newbie like me can still benefit from it.

What I learned so far:
  1. Use the Litchi Mission Hub, do not use the app for planning a waypoint mission (except for really short ones). The Mission Hub has elevation data included, something that the app is not capable of. You really, really want that.
  2. Use the Virtual Litchi Mission application together with Google Earth for planning and testing! It is really impressive to "fly" the mission in Google Earth, gives you a more or less good impression of what you planned.
  3. Know you terrain! All the virtual testing does not help if power lines are in the way which you just do not see in Google Earth. As the Google maps are probably some years old you will find some surprises in the real world. Eg. instead of a house shown on Google Earth I found a building pit with a monster high crane standing next to it.
  4. Better plan your flight too high than to low (see 3.). You can think of one (or two or three...) training flight(s) and readjust after that.
  5. Always take your battery time into account. The estimations given by the Mission Hub are usually too optimistic.
  6. A standard gimbal tilt of -16° looks reasonable to me.
  7. For speed changes and gimble adjustments you need a connection to your drone (at least for the Mavic Air) during the flight. Everything else can be flown autonomously by the drone. Especially the gimbal adjustment look awful when you lose connection during a otherwise smooth adjustment.
  8. Weather conditions have to be perfect. E.g. wind gusts will definitely set the mission and your drone at risk.
  9. The faster you fly the less cinematic is the result. The slower you fly the more boring is the result. Changing the speed in post-processing leads usually to awkward results.
  10. Do not forget to make your mind up what to do with your drone when the mission is done. Return to waypoint 1? Return to home?
So, here you have my first "longer" mission through my home town. In fact this is full of flaws and not very impressive, but anyhow, this was my first attempt.

 
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I agree with all of the things you have learnt so far, and all of the safety warnings are highly relevant (plan on the computer not the app, use Google Earth, fly high at first, check the terrain and decide your end point). The only area where I might disagree is the "optimism" of the hub mission time estimate - I have found that it is an over-estimate, with missions usually being shorter than specified. Certainly this has been true for me when the Mavic Air does not change its height during the mission...
I especially like your point number 9: the trade off between speed and smooth cinematics. My usual solution on presentation of the material is to crossfade out of the boring parts, making the mission feel rapid to the viewer whilst maintaining the nice, quiet bits. For example, in your film above we see the nice red roof of the REWE building at 1'24", but the next ten seconds have an uncomfortable sweep and some dodgy gimbal control. You could have crossfaded between 1'24" and 1'34" almost unnoticeably...
 
For your first mission, I think it was great! The music had me going for a while, I thought someone was texting me on my phone! What happened to the building with the "caved-in" roof? Was there a fire? My only comment was the intro was a little long, but I did like how you sped up the video near the end and in-between segments. The "speedups" weren't too bad. Which aircraft did you use for this? I have found that my Mavic Pro is superior to both my Phantom 3 and my Spark in missions, when it comes to smoothness and responsiveness. Also, don't forget that you need to be within control range for the whole flight because your phone/ipad/tablet controls the gimbal aiming during the mission. If you started the mission, then turned off the phone/ipad/tablet, the aircraft would still complete the mission (including altitude adjustments), but there would be no tilt changes, as those happen "live" with commands from the phone/ipad/tablet during the mission.
 
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For example, in your film above we see the nice red roof of the REWE building at 1'24", but the next ten seconds have an uncomfortable sweep and some dodgy gimbal control. You could have crossfaded between 1'24" and 1'34" almost unnoticeably...
You are absolutely right here, but my goal was to have no cuts at all (which did not work out anyway, see 3'33"). There is a lot of room for improvement, I have to admit. :)
 
For your first mission, I think it was great! The music had me going for a while, I thought someone was texting me on my phone!

Hehe, german Krautrock Motorik...

What happened to the building with the "caved-in" roof? Was there a fire?

Yes, I think I read something like that in a local newspaper.

My only comment was the intro was a little long, but I did like how you sped up the video near the end and in-between segments. The "speedups" weren't too bad. Which aircraft did you use for this? I have found that my Mavic Pro is superior to both my Phantom 3 and my Spark in missions, when it comes to smoothness and responsiveness. Also, don't forget that you need to be within control range for the whole flight because your phone/ipad/tablet controls the gimbal aiming during the mission. If you started the mission, then turned off the phone/ipad/tablet, the aircraft would still complete the mission (including altitude adjustments), but there would be no tilt changes, as those happen "live" with commands from the phone/ipad/tablet during the mission.

You are right regarding the intro, but I wanted to cover "the whole town"...

I used the Mavic Air, which is limiting me a little bit battery-and distance-wise...
 
Yes, concerning the duration of the mission, Litchi hub is rather pessimitic. Estimations by VLM are far more accurate and generally indicates much shorter times.
Concerning now the mission above which is not bad at all for a first trial, I'd be curious to see its design. My impression is that you jumped for a "focus waypoint" to an other "focus waypoint". If true, this doesn't give the smoothest gimbal movements. What I recommand (and what I use always) is to build the mission with this help for fixing gimbal pitches and headings at all waypoints and once this is done, to systematically switch to "interpolate" and to set waypoint numbers to "none" in the hub.
 
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Concerning now the mission above which is not bad at all for a first trial, I'd be curious to see its design. My impression is that you jumped for a "focus waypoint" to an other "focus waypoint". If true, this doesn't give the smoothest gimbal movements. What I recommand (and what I use always) is to build the mission with this help for fixing gimbal pitches and headings at all waypoints and once this is done, to systematically switch to "interpolate" and to set waypoint numbers to "none" in the hub.

I think you mean "POI numbers", don't you? Good idea, this is really helpful!
 
Concerning now the mission above which is not bad at all for a first trial, I'd be curious to see its design. My impression is that you jumped for a "focus waypoint" to an other "focus waypoint". If true, this doesn't give the smoothest gimbal movements. What I recommend (and what I use always) is to build the mission with this help for fixing gimbal pitches and headings at all waypoints and once this is done, to systematically switch to "interpolate" and to set waypoint numbers to "none" in the hub.
Can you say a little bit more about this? As I understand it, Litchi won't "look" at an object as I fly by it unless I:
1. set a Point of Interest
2. place a Waypoint nearby and set its "POI" to the Point of Interest number
3. let Litchi control the gimbal by choosing "Focus POI"

In the example below, I haven't flown 800m just to film trees, so I want the camera to film three nice buildings (POIs 2, 3 and 4). For the journey to the area, the Mavic has been focused on POI 2, the tallest building.
1574855619183.png
As it approaches, I want to view the building on the left, POI 4. So I define Waypoint 10 settings as:
1574858035358.png
What will be the effect of choosing Interpolate? And will it still rely on the link with the controller for smooth movement?

Many thanks.
 

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