Crazy idea ? Good idea ? Stupid idea ?

[caspian]

I live just south of Springvale in Melbourne, and the local demographic sure do.

 

[AgPhotoWings]

...or you catch them by surprise and have a chuckle over the facial expression of a bird

On a side note, I think the idea is not bad at all, I am doubtful about the feasibility though.
Another thing to point out is that, although the idea might be good- there are always numbnuts around that will then fly their drones straight into power lines which the can clearly see with their own eyes because they stand only 5m away from him, and then blame the app for not warning them...

Fantastic Photography!

 

[JoostGT3]

Fantastic Photography!

Thanks!

 

[Jwelz]

the problem then becomes the degree of separation between the sensors and the included angle to the object to be ranged. having had a little experience with this sort of ranging method for other applications, it can be done, but only within limits, and with a lot of interactive feedback from an operator.

it would be much better if the sensors could be relocated to the front motor pods just inboard of the front nav LEDs, but you then have the issue of space in the pods and legs for equipment and wiring, increased complexity of the wiring loom out through the front arm hinges, and electrical noise isolation from the motors and power wiring to them.

even then, the sensors need to be of a high enough resolution to discern any sized aerial span cable (and I've got a length of single strand fibre on my desk at work that is only about half the size of a pencil in cross section, but will do a 500 metre span no problems - no, that's not a typo) and the onboard computer needs to be able to process that and halt the aircraft from max speed before impact, or at least display it visually fast enough that the pilot could actively do the same. in all lighting conditions from dim light to haze to backlit glare, for all colours of cable, against all colours of background.

and ultimately, we as the purchaser will pay for all of the hardware and R&D to make it happen.

it's a nice idea, but I have doubts about the feasibility of implementation.

The layout to the front of the existing Mavic is not well suited to increasing the physical separation between the sensors, hence the base length which sets a limit to the range accuracy.

Adding a 3rd sensor, even with the base length currently implemented and obstacle avoidance sensor resolution would require computation of sensor a - b, a - c and b - c as opposed to just a - b, hence more processing power plus an additional sensor. Sure there's some r & d but this is a developing field and there is competition for technological advantage between vendors.

The Mavic obstacle avoidance is already capable of detecting a vertical cable of the size of most powerlines. It is only the lack of angle between the axis of the sensors and horizontal cables that makes them appear to be infinitely far away.

Given that there are more vertical and horizontal lines and edges than diagonals, it is unfortunate that the Mavic designers chose a horizontal sensor layout that is effectively blind to horizontal edges that lack distinguishing features along their length.

You can test the ability of the Mavic to see/not see a cable simply by holding it in your hand and turning it on the roll axis whule aiming it at a post or cable. Even something like the top of one of those wire mesh fences, with its repeating mesh pattern is invisible yet roll the Mavic 90 degrees to a vertical bank in your hand and it can instantly see and accurately range the fence.

Simply by introducing a vertical displacement between the existing two front range sensors, and without adding any computational complexity, the designers could have drastically increased the effectiveness of the forward sensors by enabling them to detect a vastly higher percentage of obstacles likely to be encountered in normal use.

 

[Skymax]

No harm no foul

Or harmed Fowl.

 

[Jwelz]

At the very least, the instruction manual should give photos of situations where the optical obstacle avoidance is ineffective. Any situation where the obstacle has a horizontal edge with no distinguishing features along the edge is assessed as being at an infinite distance. Such edges with repeating identical features along the length can also not be ranged. The lack of adequate instructions or explanation by DJI is reprehensible.

 

[Marko9219]

Whoa there! Facial recognition on small cameras works ONLY at close ranges (like a several feet). By time your little camera in your Mavic sees a wire, and identifies it, you are already going to be into it! Not to mention, more than half the time anyone flies these things, the camera is pointed down, not forward.

 

[Just_nick]

This is a drone that can't even detect branches from a couple feet away with its OA sensors, but it'll somehow mark power lines that you're flying to close to? I think you're vastly overestimating the current technology's abilities.

 

[JMF]

Stay away from power lines....

 

[Jwelz]

Whoa there! Facial recognition on small cameras works ONLY at close ranges (like a several feet). By time your little camera in your Mavic sees a wire, and identifies it, you are already going to be into it! Not to mention, more than half the time anyone flies these things, the camera is pointed down, not forward.

This is not about facial recognition. The Mavic forward optical sensors enable it to detect and avoid collision with objects provided it is flying within the specified speed range for obstacle avoidance. The avoidance technology compares the displacement of objects in the field of view of the two cameras. The greater the displacement. The closer the object. Given that the cameras are side by side, the parallax lateral shifts can only be seen in vertical edges and lines. There will be no detectable displacement of horizontal objects as they simply lie atop one another like any object at infinite distance is.

While the Mavic can see and stop in time to avoid collision with a 4 inch fence post, it is completely blind to a horizontal beam 12 inches tall and 20 feet wide. Hold the Mavic 10 feet from the horizontal beam and it won't see the beam. Roll the Mavic 30 degrees from level and it will detect the beam as 20 feet away. Roll the Mavic 45 degrees from horizontal and it will see the beam as being 14 feet away. Roll it 90 degrees and it will see the beam as being 10 feet away.

With good lighting and contrast and limited speed, the Mavic is entiely capable of avoiding collisions with objects as thin as a half an inch. It's simply blind to horizontally consistent obstacles.

Complex patterns such as twigs and repeating patterns are another matter entirely and have additional considerations that could be documented but lack examples.

If you've ever looked at one of those red-blue 3d images with a red filter for one eye and a blue one for the other, you see 3d depth. The Mavic OA cameras see something like the red and blue images superimposed over one another. The further apart sideways from red to blue, the closer something appears. The problem is, a horizontal line in the red image will always appear right on top of that of the blue image. In the absence of vertical clues, the horizontals appear to be at infinity and won't trigger avoidance.