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Mavic 3 Notable Blind Area for new Obstacle Avoidance System

BlairAir

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The title is not meant to be alarmist. If it gets attention, that's enough.

The usage of "360° Obstacle Avoidance" is accurate in terms of a flat, horizontal plane. In 3D space, things get, well... it's complicated 😕

Autel Evo 2 made a big splash with the OA Camera Array on it. They would alternately say it had "360° coverage", and "comes with 720° omnidirectional obstacle avoidance"

720° eh? I measured 717.3°. 😆

Anyway, looking at the M3 Manual, I saw something in the sensor coverage diagrams that I thought interesting. A fairly large uncovered area.

Going back to the E2P for reference, a YouTube channel; Jack of all Trades did OA testing, discussing the 45° angle blind spots, but ALSO blind area above the front aircraft -because the sensor array is on the back. He nearly flies into a beam under the trestle - because he comes at it with the front, top of the AC. He shows this at 10:00 in the video:


There is a significant area that the Mavic 3 cannot cover with Obstacle Avoidance. It's not likely many would have a collision because of it, but in the interest of understanding what is covered, and what the limitations are, I did a crude white board, using DJI's diagrams from page 17 of the User Manual. I tried multiple screen recorders but after close to an hour screwing around, I just used Paint and show the issue.
Comments welcome. It's all for awareness. It's FYI, not criticism of DJI. The use of wide angle cameras mounted at 45° is brilliant in its simplicity. One of those things that are incredibly obvious... AFTER the fact. As in "why didn't anyone think of this before?"

But it's not perfect. There's a point of diminishing returns, and sticking more and more sensors to cover that last sliver of space isn't necessarily a good solution.

Here is my explanation.

 
The title is not meant to be alarmist. If it gets attention, that's enough.

The usage of "360° Obstacle Avoidance" is accurate in terms of a flat, horizontal plane. In 3D space, things get, well... it's complicated 😕

Autel Evo 2 made a big splash with the OA Camera Array on it. They would alternately say it had "360° coverage", and "comes with 720° omnidirectional obstacle avoidance"

720° eh? I measured 717.3°. 😆

Anyway, looking at the M3 Manual, I saw something in the sensor coverage diagrams that I thought interesting. A fairly large uncovered area.

Going back to the E2P for reference, a YouTube channel; Jack of all Trades did OA testing, discussing the 45° angle blind spots, but ALSO blind area above the front aircraft -because the sensor array is on the back. He nearly flies into a beam under the trestle - because he comes at it with the front, top of the AC. He shows this at 10:00 in the video:


There is a significant area that the Mavic 3 cannot cover with Obstacle Avoidance. It's not likely many would have a collision because of it, but in the interest of understanding what is covered, and what the limitations are, I did a crude white board, using DJI's diagrams from page 17 of the User Manual. I tried multiple screen recorders but after close to an hour screwing around, I just used Paint and show the issue.
Comments welcome. It's all for awareness. It's FYI, not criticism of DJI. The use of wide angle cameras mounted at 45° is brilliant in its simplicity. One of those things that are incredibly obvious... AFTER the fact. As in "why didn't anyone think of this before?"

But it's not perfect. There's a point of diminishing returns, and sticking more and more sensors to cover that last sliver of space isn't necessarily a good solution.

Here is my explanation.

Good to know. Thank you very much.
 
Thanks, interesting analysis. Realistically though, I would not be depending upon the obstacle avoidance system around trees, especially at this time of the year (northern hemisphere). The fine branches with no leaves may not be detected even if they’re in the covered area.
 
Thanks, interesting analysis. Realistically though, I would not be depending upon the obstacle avoidance system around trees, especially at this time of the year (northern hemisphere). The fine branches with no leaves may not be detected even if they’re in the covered area.
You are very correct in describing the dangers of small branches being seen by cameras. (distance detection) I worked for many years as a traffic signal tech and noticed how easy it was to "not see" small diameter wires while working in the air from a bucket truck. It was so easy to miss-judge distance, so I understand the dangers of relying too much on electronics to protect my equipment.
 
I don’t recommend doing this intentionally but the folding propellors on the Mavics may allow you to recover from hitting a small branch fortunately. You’re right small branches are hard to judge and I have clipped trees several times with my M2P & luckily flown away from it ( no crash). In all these cases the sensors didn’t pickup the branches. I imagine it comes down to the resolution of the sensor and computing capability of the controller. DJI is so vague in their technical descriptions, they claim an improved system, it’s impossible to tell from the specs if the M3 actually has an improved sensing capability.
 
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Excellent analysis, very interesting and informative. Thanks for sharing.
 
Thanks for sharing
 
Thanks, interesting analysis. Realistically though, I would not be depending upon the obstacle avoidance system around trees, especially at this time of the year (northern hemisphere). The fine branches with no leaves may not be detected even if they’re in the covered area.
No argument there. This is my beef with so called Advanced RTH. I have big trees that I never launch under to avoid a Failsafe RTH going right through them. Advanced RTH tried to advance directly through, on an angle towards the Homepoint. It MAY have figured it out, but I wasn't going to end up posting yet another Mavic 3 crash video! Just give us a software switch to Straight Line RTH, DJI.
Thanks, interesting analysis. Realistically though, I would not be depending upon the obstacle avoidance system around trees, especially at this time of the year (northern hemisphere). The fine branches with no leaves may not be detected even if they’re in the covered area.
No argument there. This is my beef with so called Advanced RTH. I have big trees that I never launch under to avoid a Failsafe RTH going right through them. Advanced RTH tried to advance directly through, on an angle towards the Homepoint. It MAY have figured it out, but I wasn't going to end up posting yet another Mavic 3 crash video! Just give us a software switch to Straight Line RTH, DJI.
 
I don’t recommend doing this intentionally but the folding propellors on the Mavics may allow you to recover from hitting a small branch fortunately. You’re right small branches are hard to judge and I have clipped trees several times with my M2P & luckily flown away from it ( no crash). In all these cases the sensors didn’t pickup the branches. I imagine it comes down to the resolution of the sensor and computing capability of the controller. DJI is so vague in their technical descriptions, they claim an improved system, it’s impossible to tell from the specs if the M3 actually has an improved sensing capability.
Indeed, and the fastest way to find out is what would be called "destructive testing" - I'll leave that to the big budget YouTube stars, thanks. I admit I'm curious to explore Active Track 5.0 when it's ready. I have taken a half dozen drones through this low canopy of trees that a long walkway. The Evo 2 Pro's Dynamic Track was too dynamic for me. I nearly stroked out just watching it afterwards, since I never looked back during the event; just walked through, whispering "Autel Care" as a mantra, never looking back.
 
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