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RTH accuracy.

MoToad

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My Mav 3 Classic continually missed the mark by a foot or to thruout its life with me. Never would land on the target ring it took off from. Never changed thru a couple of updates. So I was pleasantly surprised to find my first RTH land exactly where it took off from. Now I've only had a couple of chances to fly so far and it didn't happen on my second flight. But there was a difference between one and two. The first perfect RTH was done completely by the drone. Never touched the controls. The second I moved the camera around some and it seemed to stop it from using it. I take it the camera is a big part of landing where it took off from? Or not?
Edit: Just to clarify. This is my new Air3S i am referring to.
 
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. I take it the camera is a big part of landing where it took off from? Or not?
There are two ways your drone locates the launch point for returning to home.
1. GPS alone - that will give you a return accuracy of a couple of feet.
2. Precision Landing Feature - This uses optical technology to record the fine details around the launch point and match them on return.
It will give accuracy of an inch or two if your takeoff meets the requirements for this feature.
For details of Precision Landing, see page 23 of your manual here:

ps .. PL doesn't use the main camera.
 
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Not sure about the Air3S, but on my original MP, in order for precision landing to work, when taking off you must go straight up to a height of at least 10 meters with no lateral movement. The allows the craft to get a "picture" of the landing spot. I can consistently land almost exactly where it took off.
 
My Air 3S is spot on when landing too. Don’t touch a thing on RTH, observe the cross hair icon when landing and you will see it adjusting to its original take off coordinates…remarkable precision. Even my Air 2S is pretty spot on. What I’m going to see with both drones is trying night flights using my landing light on the belly for take off and landing. The Air 3S has the landing cross hair icon. With the Air 2S I select the cross hair grid line to observe the landing behaviour.

MoToad, safe and accurate landings ✅

🇨🇦👍
 
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My Air 3S is spot on when landing too. Don’t touch a thing on RTH, observe the cross hair icon when landing and you will see it adjusting to its original take off coordinates…remarkable precision. Even my Air 2S is pretty spot on. What I’m going to see with both drones is trying night flights using my landing light on the belly for take off and landing. The Air 3S has the landing cross hair icon. With the Air 2S I select the cross hair grid line to observe the landing behaviour.

MoToad, safe and accurate landings ✅

🇨🇦👍
Mines about 2cm out on a bad day
 
Precision Landing works by using the VPS capability, same tech that hovers precisely at low altitude.

The drone must ascend vertically on takeoff to 7m/20ft with a brief pause to capture the image below the drone with the VPS cameras. It's critical there are no yaw/pitch/roll inputs AT ALL during this ascent – that will cancel the Precision Landing initialization, and RTH will land with only GPS accuracy.

On RTH, when Landing the drone will use the saved image to compare to the live view from the VPS cameras to adjust position. This is how a low altitude hover works – when there is no control input and the drone is below the VPS altitude (30-45ft depending on model), it captures an image of the ground below, and then using a technique called "optical flow" the Flight Controller in the drone makes contant pitch and roll adjustments to keep the live view aligned with the captured image.

Bottom line: To enable PL, ascend on takeoff to 20ft without any other stick input, count one-two, go fly. RTH will land on a dime.
 
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Mines about 2cm out on a bad day
I wonder, with doing what I said, if I cancel RTH and re RTH, if that would correct. Not touching anything from that point on. Around here lately we have low cloud till about noon. Then we have had brilliant sky. Hope to get out today for a bunch of practice RTHs.
 
I wonder, with doing what I said, if I cancel RTH and re RTH, if that would correct. Not touching anything from that point on. Around here lately we have low cloud till about noon. Then we have had brilliant sky. Hope to get out today for a bunch of practice RTHs.
The drone would still be using the same information about the home point. There's no reason to expect a different result.
 
The drone would still be using the same information about the home point. There's no reason to expect a different result.

If PL was properly initialized, and the drone is far enough away to not land where it is (review RTH operation in the manual), then yes it will perform a Precision Landing.
 
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Take some shiny tape and make a hashtag on your landing pad, with this and if you follow Droning on and on...post No.7 your drone will hit its mark every time. 20 feet seems a little high but would work fine if you do like he is describing. the hashtag you make must be made from tape or such and will not work nearly as well if you Paint it on the Landing pad.
 
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The colour is irrelevant.
All the VPS needs is a texture or pattern it can recognise.

In fact, I believe the OA cameras are grayscale.

At least that's the presentation when displayed in Fly.
 
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