Flights on hills

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So, I live on a sloped street/hill. When I take off, I’m at 2-3 feet. As soon as I head towards the neighbors I’m so much higher and the next neighbor even higher. Basically, at the end of my block I’m already over my 300ft flight limit.

Is there a way to have my quad know it’s only 300ft in the air from its current location, and now from its return spot?

Did that question make sense?
 

Meta4

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Is there a way to have my quad know it’s only 300ft in the air from its current location, and now from its return spot?
No ... the drone doesn't have any sensors that can measure height above the ground (except for the short range VPS system).
So all heights are relative to the launch point.
That won't create any problems with RTH.
 
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No ... the drone doesn't have any sensors that can measure height above the ground (except for the short range VPS system).
So all heights are relative to the launch point.
That won't create any problems with RTH.

that makes sense.... what if I walked with the drone? Would it still use the RTH for height, or my remotes/ipads new location?

I ask because I’ve flown the drive about 2-3 blocks down from my home and I get about 7-800 feet above ground and it get warnings from the nearby airport. It’s also hundreds of feet higher than my drive is allowed to get with me flying it on my own.
 

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that makes sense.... what if I walked with the drone? Would it still use the RTH for height, or my remotes/ipads new location?
I ask because I’ve flown the drive about 2-3 blocks down from my home and I get about 7-800 feet above ground and it get warnings from the nearby airport. It’s also hundreds of feet higher than my drive is allowed to get with me flying it on my own.
When you power on the drone, it uses the reading from the barometric sensor in the IMU as its zero height.
All heights in your flight data are based on that zero height, no matter how far you move or what you do with your iPad etc.
It's up to you as the pilot to know where the drone is and keep it within 400 ft of the ground below it (or less if there are airport restrictions).
 
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And there is only on you to estimate you'll not go above 400ft AGL. But also that doesn't mean that you will not be over 400ft from your take off point if the terrain goes up. You can fly at altitude of 1000ft or more as long as you not exceed 400ft AGL.
 
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Flying a prescribed route using Litchi, you can choose to set all the waypoints at a certain altitude "above ground". Then your craft will always be at the chosen height relative to the ground. See the notations on the waypoint settings here...

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AGL Waypoints.jpg


Note: The steeper and more rugged the terrain, the closer-together you'll want to set the waypoints.

On this flight the waypoints were never set to more than a couple hundred feet "Above Ground", yet the range of altitude was about 800 feet.


Steve
 
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I was going to find a video and do all the processing. Too much work. lol. I was barely over the tree tops and was close to 500 feet as recorded by the app. The app was warning me that I was flying too high. That was in front of my house trying to clear my neighbor's house. It's also easy to fly negative numbers and be too high AGL.
 
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No ... the drone doesn't have any sensors that can measure height above the ground (except for the short range VPS system).
So all heights are relative to the launch point.
That won't create any problems with RTH.
What I never understood in DJI’s P3 design (I guess the approach is still present in further generations), is why the drone is not using its GPS capability to measure on Z axis too (height), value from which will extract the "ground_elevation_at_drone_location" (see the csv file, column based I guess on Google Earth mapping), to finally obtain drone's present elevation above ground.

Actually, except "height_above_takeoff", the csv file is containing too the column "height_above_ground_at_drone_location", which is exactly what we need on screen in hilly environments !
 

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What I never understood .. is why the drone is not using its GPS capability to measure on Z axis too (height)
Mostly because it's not as accurate as the barometric sensor.
"height_above_ground_at_drone_location", which is exactly what we need on screen in hilly environments !
Estimating your drone's height isn't as great a problem as some forum members make out.
 

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When I got my first drone, a P3P, I thought it would be great to do a video of the golf course behind me. I live in Florida so the terrain is rather flat. I left all the settings at default and off I went. The sun was very bright and I could hardly see the screen let alone the drone. I went about a thousand feet up the golf course when I lost the signal. Panic struck in and I ran up the golf course looking for it and trying to get my signal back. Then I drove around looking. Finally I checked the GPS on the remote to see where it was last. It stopped between 2 houses. It struck the top of a tree ( 100 plus feet tall) and rolled down onto some bushes and landed next to a house. In Clermont Florida the terrain is rolling hills not flat. It doesn't look like much to the eye but it is at least 300 feet plus that tree. That is when I started repairing gimbals. I am now very careful about knowing the terrain before flying. I am also pretty good at repairing gimbals. LOL
 
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When I got my first drone, a P3P, I thought it would be great to do a video of the golf course behind me. I live in Florida so the terrain is rather flat. I left all the settings at default and off I went. The sun was very bright and I could hardly see the screen let alone the drone. I went about a thousand feet up the golf course when I lost the signal. Panic struck in and I ran up the golf course looking for it and trying to get my signal back. Then I drove around looking. Finally I checked the GPS on the remote to see where it was last. It stopped between 2 houses. It struck the top of a tree ( 100 plus feet tall) and rolled down onto some bushes and landed next to a house. In Clermont Florida the terrain is rolling hills not flat. It doesn't look like much to the eye but it is at least 300 feet plus that tree. That is when I started repairing gimbals. I am now very careful about knowing the terrain before flying. I am also pretty good at repairing gimbals. LOL
That's when you learned the citrus tower was over 300 feet above sea level. You live in the Hillcrest part of Florida. I also use to live in Leesburg.
 

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