Size, scale, depth perception when flying over featureless terrain or without reference size objects

[lomposlapos]

Think of flying above featureless/unknown scale terrain (over water, desert sand, arctic ice/snow, over a volcano) or in a major canyon or around a big (200 m diameter) rocky island, where there are no people, houses, roads, etc. that would help to calibrate size and distance and height AGL.

What are the options to estimate distance from an object or height above the ground or water (AGL) for safe operation (i.e., not hitting anything)? Let's say you approaching a rocky island that is 4 km away from mainland home point, and you want to go close enough but not crashing into... at what point do you stop getting close?

 

[Meta4]

What are the options to estimate distance from an object or height above the ground or water (AGL) for safe operation (i.e., not hitting anything)?

You can do a little homework with Google Earth to find distances and calculate heights.

Let's say you approaching a rocky island that is 4 km away from mainland home point, and you want to go close enough but not crashing into... at what point do you stop getting close?

You do have vision on the screen to help.

 

[lomposlapos]

You do have vision on the screen to help.

Does not help if there is zero reference in size on the screen. Like landing on moon using visual cues only, can not judge distance.

 

[Meta4]

Does not help if there is zero reference in size on the screen. Like landing on moon using visual cues only, can not judge distance.

Have you had this problem or are you just anticipating it?
If you want to fly to an island 4 km away, you know how far it is and you have the distance showing on your screen to let you know how much further the target is.

 

[Hummingbird.UAV]

Think of flying above featureless/unknown scale terrain (over water, desert sand, arctic ice/snow, over a volcano) or in a major canyon or around a big (200 m diameter) rocky island, where there are no people, houses, roads, etc. that would help to calibrate size and distance and height AGL.

What are the options to estimate distance from an object or height above the ground or water (AGL) for safe operation (i.e., not hitting anything)? Let's say you approaching a rocky island that is 4 km away from mainland home point, and you want to go close enough but not crashing into... at what point do you stop getting close?

Approaching a rocky island 4km away. Well to start you don't have line of sight of your drone, that probably maxes out at .5km. So you are flying off the screen, FPV. Hopefully a big screen. Flying off the screen and approaching objects has all to do with changing perspective to judge distance to objects. It requires practice while you can see the drone and the object directly and on the screen to know how close things are that you see on the screen. Hope that helps.

 

[RadioFlyerMan]

Think of flying above featureless/unknown scale terrain (over water, desert sand, arctic ice/snow, over a volcano) or in a major canyon or around a big (200 m diameter) rocky island, where there are no people, houses, roads, etc. that would help to calibrate size and distance and height AGL.

What are the options to estimate distance from an object or height above the ground or water (AGL) for safe operation (i.e., not hitting anything)? Let's say you approaching a rocky island that is 4 km away from mainland home point, and you want to go close enough but not crashing into... at what point do you stop getting close?

I've been your scenario several times, flying FPV and having no sense of scale. In such cases I simply rely on the distance reading of the forward and downward sensors. And then I assume a large margin of error so I don't get too close.

Here's an example of getting close to a featureless object or an object with no known scale:

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[Montana John]

I've been your scenario several times, flying FPV and having no sense of scale. In such cases I simply rely on the distance reading of the forward and downward sensors. And then I assume a large margin of error so I don't get too close.

Here's an example of getting close to a featureless object or an object with no known scale:

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Great match of music with skillful flying. Onward!

 

[BigAl07]

It sounds like you're anticipating a bigger problem than is likely to happen. While you can't "accurately" just distance you can tell when you're relatively close to something when flying FPV like you're suggesting.

Go out and do some practice flights near your home and you'll get a good feel for what to expect.

 

[paulatkin73]

Think of flying above featureless/unknown scale terrain (over water, desert sand, arctic ice/snow, over a volcano) or in a major canyon or around a big (200 m diameter) rocky island, where there are no people, houses, roads, etc. that would help to calibrate size and distance and height AGL.

What are the options to estimate distance from an object or height above the ground or water (AGL) for safe operation (i.e., not hitting anything)? Let's say you approaching a rocky island that is 4 km away from mainland home point, and you want to go close enough but not crashing into... at what point do you stop getting close?

I would say, if you go FPV - get good goggles. Screen is not the best way to see. Hdo fatsharks, or dji product, or epson - anything that can take hdmi input.

 

[RadioFlyerMan]

Great match of music with skillful flying. Onward!

Thank you!

 

[lomposlapos]

I've been your scenario several times, flying FPV and having no sense of scale. In such cases I simply rely on the distance reading of the forward and downward sensors. And then I assume a large margin of error so I don't get too close.

Thank you for the advice, I see you surely mastering the exact situation I am referring to. Excellent videos!

Can I ask you please what do you use as an initial video setting in situations like the above shoot (ISO, f/, shutter, etc.), and the suggested focusing method (manual, AF and keep tapping...)?

 

[RadioFlyerMan]

Thank you for the advice, I see you surely mastering the exact situation I am referring to. Excellent videos!

Can I ask you please what do you use as an initial video setting in situations like the above shoot (ISO, f/, shutter, etc.), and the suggested focusing method (manual, AF and keep tapping...)?

Keep in mind they are shot with an MPP fixed aperture . I was shooting in 4K, Truecolor, with white balance set to sunny or cloudy. As far as exposure, back when I did those videos, I was not very scientific at all. I set everything to manual, ISO at 100, did my focus in automatic then locked it in to manual, then moved the exposure wheel until the histogram looked good. Actually a very poor way of doing it because sometimes I was lucky, and sometimes the clips would be over exposed.

Today I have a significantly different approach... see this link

Videos too bright

I was out flying yesterday and all the video was washed out with too much light. I didn't think there was much more light than at other times. It was between 4 and 5 pm and even the video taken while flying away from the sun was over exposed. My Chrystal Sky monitor was not showing the over...

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