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A wall flying at full speed.

dmenguez

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Anyone know what would happen if I'm flying in positioning mode (P) and I drive my Mavic 2 at 27 mph against a wall?
Would anti-shock systems work?
Or maybe, even if it detects the wall, it would not give you time to slow down?
Someone has tried?
Thank you
 
It happens that sometimes, when I fly around a mountain, if I tell him to go home, the drone will return in a straight line, making the path shorter and at maximum speed. Would you dodge the mountain to go home?
 
When I am in flying in P-Mode I can not fly my drone into anything because the vision / collision sensors are on. I have tried flying it into stuff and there was never a chance of doing so with the sensor enabled. The AC would also stop at least 6-10 feet away and thats only when I was flying at full p-mode speed!
 
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Someone has tried?
I don't think anyone has ever "tried" Not unless they had deep pockets and wanted to post on youtube like some do when a new product comes out just for clicks.
Nope, never tried, but I am sure a few people have had some major accidents with their drones.
 
I don't think anyone has ever "tried" Not unless they had deep pockets and wanted to post on youtube like some do when a new product comes out just for clicks.
Nope, never tried, but I am sure a few people have had some major accidents with their drones.
My question is: If flying around a building for example ... and the drone is told "come home" ... return around the building? or try to return by the shortest path crashing against it?
 
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I don't think anyone has ever "tried" Not unless they had deep pockets and wanted to post on youtube like some do when a new product comes out just for clicks.
Nope, never tried, but I am sure a few people have had some major accidents with their drones.
I may be missing something here, but how could you crash a dji drone in p-mode when all the sensors are on? I thought that is what the OP was asking. I have tried to crash my drone, when I first got it when I was testing the sensors out. I know its a bit stupid, but I choose a soft target (me) and flew the drone at quarter speed, half speed and then full speed in p-mode and each time there was no way I could ever get the drone to crash lol. That's the whole point of having an expensive drone with safety features!
 
My question is: If flying around a building for example ... and the drone is told "come home" ... return around the building? or try to return by the shortest path crashing against it?

This will depend on the height settings for the Return to Home feature. If there was a building in the way and the drone losses contact with the RC then the drone will activate return to home, or whatever settings you have set for when contact is lost.

Even if the height settings is not high enough the drone will not fly into the building it will try and move around or over it as long as there is enough light for the sensors to work correctly!
 
My question is: If flying around a building for example ... and the drone is told "come home" ... return around the building? or try to return by the shortest path crashing against it?
Have a look at your manual ... you'll find an explanation like this ...
OADRTH.JPG
Make sure you understand all of the 'Return to Home' features that your Drone has, and what the various options that you can turn on and off actually do (and what limitations there are!!) ... !!!! Then !!!! Learn to fly without trusting them ... The bottom line is that if you can't see your drone to trust that it will avoid some obstacle on RTH, then a) first try not to get in that situation in the first place, b) fly the drone to a point where you can see that it's in clear air, and c) use RTH as a last resort!

Knowing how to fly the drone back toward you is a basic but important flight skill, that one day you'll be pleased you mastered. That realisation comes the day you push left to fly right - without having to think about it - to avoid the tree as you bring the drone back to you.
 
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I may be missing something here, but how could you crash a dji drone in p-mode when all the sensors are on? I thought that is what the OP was asking. I have tried to crash my drone, when I first got it when I was testing the sensors out. I know its a bit stupid, but I choose a soft target (me) and flew the drone at quarter speed, half speed and then full speed in p-mode and each time there was no way I could ever get the drone to crash lol. That's the whole point of having an expensive drone with safety features!
I am glad I’m not your life insurance agent. :p
 
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The sensors MAY stop your drone from hitting a wall but they are not perfect. They are affected by speed, lighting conditions, temperature, angle of attack, and the characteristics of the object. Don’t depend on them.
 
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Anyone know what would happen if I'm flying in positioning mode (P) and I drive my Mavic 2 at 27 mph against a wall?
Would anti-shock systems work?
Or maybe, even if it detects the wall, it would not give you time to slow down?
Someone has tried?
Thank you

My original Mavic Pro does a great job of stopping when using the front facing optical avoidance/detection cameras even at full speed P mode when there are clear unique vertical edges in the field of view.

As far as horizontal lines or markings are concerned, all forward DJI obstacle avoidance sees them as infinitely far away like the horizon.

I propped a 12' 2 by 4 in front of a plain wall. From 8 feet away, the Mavic detected the vertical stud as 8 feet away. At a 45 diagonal, it read it as being 11 feet away. At 60 degrees off vertical, it thought it was 15+ feet away. At horizontal, it didn't see any obstacle. This is because the steroscopy determines distance to objects by counting how many pixels apart an object in one image is from where it is in the other. Because the cameras are at the same level, any uniform object parallel to the axis between the cameras appear to lie stop each other with no distance between them which is what you get for objects at infinity. You have the same problem with uniformly spaced identical objects or when there are no distictly identifiable shapes in the obstacle avoidance cameras field of view.

Accuracy gets worse when there are no distinct edges, the light is poor or the lenses are dirty or facing directly into light sources causing flare or internal lens reflections. Under optimal conditions with still air or a head wind, the Mavic Pro 1 can stop in time at full P mode speed so I'd expect similar performance from the 2.
 
The sensors MAY stop your drone from hitting a wall but they are not perfect. They are affected by speed, lighting conditions, temperature, angle of attack, and the characteristics of the object. Don’t depend on them.

Good call, Camino. I have a $300 repair bill from DJI proving that the sensors didn't stop our Mavic Pro from hitting a wall. "Testing" this is crazy unless you have a bunch of money laying around to use for kicks.

And yes, I was "testing" mine. How did it happen? I was slowly approaching my house testing to see where, when and if the sensors stopped it. And no, it wasn't the sensors' fault. It was my fault for not realizing how bad the light had gotten. (It was about sundown.) My depth perception was not good enough and I slowly flew it into the wall.

The lesson(s) learned: Camino is exactly right, the sensors ARE good but not perfect. Lack of available light caused mine to fail to sense the wall. Second lesson: Don't take unnecessary chances with your drone even if you are sure the sensors are working fine. Trust me, it's not worth it.

I very much appreciate the fact that the sensors are there, but I NEVER depend on them. Just like RTH and precision landing; I use RTH almost every time I land, but you can believe that I watch it like a hawk while it's doing it, especially if it's late in the day and the light is failing.

Bottom line: Why take totally unnecessary risks with a $1000 piece of equipment? Just my opinion...
 
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Anyone know what would happen if I'm flying in positioning mode (P) and I drive my Mavic 2 at 27 mph against a wall?
Would anti-shock systems work?
Or maybe, even if it detects the wall, it would not give you time to slow down?
Someone has tried?
Thank you

It would stop before it hit the wall if you were in P or T mode and had the obstacle sensors active. Never assume the sensors will work though - they do work very well but they are more of a "plan B" rather than something you should place ultimate trust in. Things like bright sunlight and too steep of a flight angle (attitude) can render the sensors temporarily useless, and that can happen when you least expect it.

If you're curious how drones hold up to crashes, people on YouTube have purposely flown them full speed in Sport mode into a tree, shot them with hoses and pressure washers, etc. and they are surprisingly durable, but the results are pretty well as expected - not something any normal person would ever want to do.

Also note that the side sensors on the Mavic 2 are not stereoscopic, so they do not work in real time like the others do, and they only work in tripod mode, point of interest, circle, helix, boomerang, timelapse and active track. They work by comparing images, so they only work with slower consistent/predictable movement.
 
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Anyone know what would happen if I'm flying in positioning mode (P) and I drive my Mavic 2 at 27 mph against a wall?
Would anti-shock systems work?
Or maybe, even if it detects the wall, it would not give you time to slow down?
Someone has tried?
Thank you

Just to verify my earlier response, I had a look at the manual for the Mavic 2. This claims a maximum speed for effective forward obstacle avoidance is 14 metres per second so it should be able to stop in time provided the obstacle had the correct attributes for detection and the light was good. Maximum P mode speed is limited by forward tilt angle which is set not to exceed 25 degrees. In S mode, tilt is allowed to go up to 35 degrees which allows the greater speed but the obstacle avoidance is disabled because it is not sufficiently capable at that speed. The vertical field of view of the front obstacle cameras is 70 degrees and at a S mode tilt angle of 35 degrees, anything in front of a horizontal flight path at the level of the drone and immediately above would be undetected. In P mode, there is a 10 degree upward angle of view cushion above the flight path.

Wind speed can affect the rate of closure with a stationary obstacle as the ground speed will vary despite the tilt angle limit. The DJI specs for speed are based on airspeed and not ground speed. A tailwind would reduce the air speed figure for effective forward obstacle avoidance below 14 m/sec.

Interestingly, the rearward obstacle cameras are over/ under rather than side by side so it would be blind to vertical objects like flagpoles.
 
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