Litchi large perfect circle

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i am using a Phantom 3 Professional and Litchi. I want to program a mission that flies a perfect circle with a 3000 foot radius focused on a central waypoint. I don't want to use obit as I understand it has a radius limit too small and I want it to be repeatable, always starting and ending at the same point. The idea is to fly the same large circle around my 185 acre farm in different seasons. I've tried to draw a circle but can't get the distances and curve lengths perfectly symmetrical. Is there a circle function other than orbit?
 
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Whew! That's ambitious! That's an over 18000 ft (over 5 km) mission. Not even going to talk about VLOS issues! Anyway, I would try manually drawing the mission, only not freehand. I would use a circle template and a stylus to draw on my tablet. Pull up the map of your farm and zoom out until the scale matches your template the use the stylus to draw the mission around it. Let Litchi fill in the waypoints then set your POI in the center and link all of the waypoints to that POI. Use curved paths and set it to autorecord on take off (if you are shooting video). For stills, you will have to use straight lines and set the mission to take the shoots at each waypoint. Store the mission and repeat as often as desired. If the total length is too long, you could use the total mission as the base and break it into segments that you save as separate missions then fly each in turn. Going that route would also allow you to change batteries and relocate your takeoff position between segments. Others may have better ideas, this is one way I think would work. Let us know how it works if you try it.
 
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Mark The Droner

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That's gonna be tough. Even if you successfully came up with the "perfect" mission, the craft will tend to be off by a bit relative to each mission, some horizontally and more vertically. And then you have wind causing problems - one mission to the next.

Re your last question, you can use IOC home lock to draw a circle, but that's not a mission.

Good luck.
 
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I like the idea about drawing around a template. I'd use a suction cup so it didn't move.and draw it with a stylus as suggested. You can then move that circle and adjust its size where ever you want it on the map.
 
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Phantom,

I think Richard is pretty much dead on. Your bird should do 18k' without issue as long as you make sure you are starting out with "everything" fully charged, you have established a good working speed and the weather cooperates. Prior to the introduction of the orbit function in Litchi, that's exactly how I did orbits, by taking an object and tracing a circle with a stylus on my pad. It's not as easy as it sounds but it will work. A word of warning if you'll be doing this often, invest in a tracker for your bird. It'll pay for itself the first time you need to use it. I use the Marco Polo stuff on all of my birds. Good luck!

Jerry
 
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i am using a Phantom 3 Professional and Litchi. I want to program a mission that flies a perfect circle with a 3000 foot radius focused on a central waypoint. I don't want to use obit as I understand it has a radius limit too small and I want it to be repeatable, always starting and ending at the same point. The idea is to fly the same large circle around my 185 acre farm in different seasons. I've tried to draw a circle but can't get the distances and curve lengths perfectly symmetrical. Is there a circle function other than orbit?
I've created a simple circle, didn't fly test it yet. Search for Circle on FlyLitchi Hub, it can be moved to your location and resized, rotated.

Looking at the map it seems kind of squashed, but maybe can create good results. If your primary goal is to compare different seasons, the circle doesn't need to be perfect, more important would be the repetition precision (GPS related).
 
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All,

Thanks for the advice!

Ed,

I tried to search for the circle in the Litchi Hub but only found locations, like Circle K and Circleville, OH (home of the pumpkin festival). If I did find it I'm not sure how to move it but could probably figure it out.

I've never used Litchi Hub...I'm new to Litchi and have only drawn and clicked missions on my iPad. Getting that circle closer to perfect freehand has been tough. I like the suction cup idea and may give that one a shot but don't know if I have time this weekend. I was hoping for an insert function, like you get in Word, where you can just drop a circle, resize and move it but it sounds like that doesn't exist.

I've done my hand-drawn mission and can complete it with about 20% battery left even slowing it down a bit to keep the props out of the video, but I think a tracker is a good idea particularly if it were to drop in wooded areas or tall corn.
 
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A 3000ft radius with a 94deg FOV lens you will need massive inaccuracies in your circular oath for it to be evident in your footage. As long as the gimble tracks your POI everything will be good.
 
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A 3000ft radius with a 94deg FOV lens you will need massive inaccuracies in your circular oath for it to be evident in your footage. As long as the gimble tracks your POI everything will be good.
Good observation. OP could create a pentahedron (or hexahedron or etc) and with enough curve radius it would either be a perfect circle, or it would fly like one.
 
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i am using a Phantom 3 Professional and Litchi. I want to program a mission that flies a perfect circle with a 3000 foot radius focused on a central waypoint. I don't want to use obit as I understand it has a radius limit too small and I want it to be repeatable, always starting and ending at the same point. The idea is to fly the same large circle around my 185 acre farm in different seasons. I've tried to draw a circle but can't get the distances and curve lengths perfectly symmetrical. Is there a circle function other than orbit?
Iam doing a project like yours,I started in June.Be ready for alot of time at the editing stage as the bird will deviate its flight path on each flight. Its better to film in 4K then you have room to adjust the picture in the edit. I divided the playing time by 12 and then made 12 video tracks.Sync all your starts and place a long cross fade at your division markers. Its a challenge but Im happy with it so far. Good luck.
 
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Vid,

A bit crude (my editing skills are horrible) and not a circle but you'll get the idea. It's six miles so I had to speed it up to keep it from being too boring and 15 minutes long.

Jerry

 
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Vid,

A bit crude (my editing skills are horrible) and not a circle but you'll get the idea. It's six miles so I had to speed it up to keep it from being too boring and 15 minutes long.

Jerry

cool video. I would try using dissolves instead of cuts though
 
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All,

Thanks for the advice!

Ed,

I tried to search for the circle in the Litchi Hub but only found locations, like Circle K and Circleville, OH (home of the pumpkin festival). If I did find it I'm not sure how to move it but could probably figure it out.

I've never used Litchi Hub...I'm new to Litchi and have only drawn and clicked missions on my iPad. Getting that circle closer to perfect freehand has been tough. I like the suction cup idea and may give that one a shot but don't know if I have time this weekend. I was hoping for an insert function, like you get in Word, where you can just drop a circle, resize and move it but it sounds like that doesn't exist.

I've done my hand-drawn mission and can complete it with about 20% battery left even slowing it down a bit to keep the props out of the video, but I think a tracker is a good idea particularly if it were to drop in wooded areas or tall corn.

I've created a simple tutorial (attached image), hope it helps. Did it on my computer, not tablet, not perfect, but it's a start.

In case you succeed creating it, start on a smaller scale, just to try the concept. In case you are satisfied, go to full size.

Good luck ;)
 

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I was watching football with a relative who is an engineer and works with guidance systems. I threw the problem his way and he created my perfect circle by using a Great Circle calculation. He gave me 99 waypoints, the max that can imported into Litchi, in an excel spreadsheet that he then imported into my Litchi account. Each waypoint is exactly 0.8 KM from the center of the farm. The entire circle covers 22,102 ft. in 10 minutes at cruising speed, which I may slow a bit to keep the props from dropping into the frame. He even cross-referenced Google's terrain data to get the distance above sea level for each waypoint, that way I can adjust altitude for the hills in the area. I was going for what would keep me under 400 ft. AGL at the lowest point on the circle, which had me lower than I wanted to be at the top part of the farm. I'll give it shot this weekend, weather permitting!
 
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I was watching football with a relative who is an engineer and works with guidance systems. I threw the problem his way and he created my perfect circle by using a Great Circle calculation. He gave me 99 waypoints, the max that can imported into Litchi, in an excel spreadsheet that he then imported into my Litchi account. Each waypoint is exactly 0.8 KM from the center of the farm. The entire circle covers 22,102 ft. in 10 minutes at cruising speed, which I may slow a bit to keep the props from dropping into the frame. He even cross-referenced Google's terrain data to get the distance above sea level for each waypoint, that way I can adjust altitude for the hills in the area. I was going for what would keep me under 400 ft. AGL at the lowest point on the circle, which had me lower than I wanted to be at the top part of the farm. I'll give it shot this weekend, weather permitting!
That's a really useful relative ;)

Maybe one day he could write your own personal app ;)
 
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I searched for Circle and didnt get a direct hit. What part of the country should I look in?

I've created a simple circle, didn't fly test it yet. Search for Circle on FlyLitchi Hub, it can be moved to your location and resized, rotated.

Looking at the map it seems kind of squashed, but maybe can create good results. If your primary goal is to compare different seasons, the circle doesn't need to be perfect, more important would be the repetition precision (GPS related).
 

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