If you go to the 7:10 mark on the posted video you will see a quad flying on 2 motors, controlled flight on 2 motors. Ive also seen a quad fly similarly on 3 motors. As we can all see its clearly possible. Why has DJI not incorporated this technology in its products? Is it simply that failures sell more drones? I really dont see any other reason for it. This video is 4 years old. It really bothers me that DJI could easilly integrate this technology, most likely with a firmware update but most certainly  could have incorporated it in their new models going at least 4 years back, but they havent. Every DJI since the Phantom 2 should have this capability. Sometimes I just really dont like DJI. They could make drones safer and more redundant, but they dont. They do what is in their best interest but could care less about their customers best interest. I find it a little disturbing. They could add a small backup power supply for gps locating after a crash, but they dont. They could do an onboard self susstained tracker, but they dont. They could prevent motor/prop failure crashs, but they dont. They will incorporate strick geo fencing, but thats for them, not you. They could do so much more to protect you the operator/owner but if it doesnt protect them then they have no interest. Bad form DJI!

DJI could easily integrate this technology, most likely with a firmware update but most certainly  could have incorporated it in their new models going at least 4 years back, but they havent.

Really?
DJI could do that easily but they aren't interested?
If it was as simple as you think, don't you think DJI would have done it already?
Perhaps it's not such a simple matter at all.
Did you think that just maybe, there's a good reason (or two) that DJI haven't implemented this?
It's one thing for a purpose built lightweight drone to do that but it's a very different matter for a camera drone optimised to fly for 30 minutes.  The weight is just too much for it to fly with only two or three motors.
And how common is it for a Phantom to lose a motor?

Labroides Posted at 2017-7-16 08:17
DJI could easily integrate this technology, most likely with a firmware update but most certainly  could have incorporated it in their new models going at least 4 years back, but they havent.

Really?

Yeah, I do think it would be easy to incorporate the teck. Its just a computer algorithm and I think its a safe bet to say that the p4 has much more processing power than the one in the 4 year old video. Do I think they  have a good reason for not doing it? Sure, crashes sell drones, thats the only reason they need. There is another video floating around youtube of a quad with a similar design to phantoms flying on 3 motors. How often is there a motor failure? Probably not often but youtube is full of videos of prop failures. Ive offered proof that it can and does work and you've offered nothing more than conjecture that it wont. Do you have any factual information that a phantom could not fly on 3 motor? If not, thanks for you offering your opinion. Ive made note of it, and disregarded it. Thanks

You can make a note of my opinion, too, and disregard it.  This video does not show a failed motor.  It shows four working motors and two of them (note that the number is two, not one) have props that are compromised.  Both of these compromised props are on either side of the body of the quad.  How convenient.  This is not the same as a single failed motor.  It's not even close.  

You say you've seen a quad flying on three motors?  That sounds a lot like conjecture.  Let's see it.  Show us a video of a quad flying controlled with three working motors and one failed motor and we can consider getting out the torches and pitch forks.

Mark The Droner Posted at 2017-7-16 12:20
You can make a note of my opinion, too, and disregard it.  This video does not show a failed motor.  It shows four working motors and two of them (note that the number is two, not one) have props that are compromised.  Both of these compromised props are on either side of the body of the quad.  How convenient.  This is not the same as a single failed motor.  It's not even close.  

You say you've seen a quad flying on three motors?  That sounds a lot like conjecture.  Let's see it.  Show us a video of a quad flying controlled with three working motors and one failed motor and we can consider getting out the torches and pitch forks.

Here ya go.

Anything else?

Actually I have seen that vid.  I just forgot about it.  Well done.  

Mark The Droner Posted at 2017-7-16 12:20
You can make a note of my opinion, too, and disregard it.  This video does not show a failed motor.  It shows four working motors and two of them (note that the number is two, not one) have props that are compromised.  Both of these compromised props are on either side of the body of the quad.  How convenient.  This is not the same as a single failed motor.  It's not even close.  

You say you've seen a quad flying on three motors?  That sounds a lot like conjecture.  Let's see it.  Show us a video of a quad flying controlled with three working motors and one failed motor and we can consider getting out the torches and pitch forks.

So what kind of pitch fork are you bringing? I prefer a trident but bring whatever you like.

Duchunter Posted at 2017-7-16 12:44
Anything else?

No ... just the same issues.
It might be possible for a lightweight, purpose built drone to do that but it's a very different matter for a Phantom with enough battery for 30 minutes flying time.
Power to weight is a huge factor in the issue.
I have a feeling that the designers that can get a P4 pro together might have a few tech ideas that are slightly beyond your level.
The notion that DJI could incorporate this but choose not to so they can sell more drones doesn't stack up.
The number that crash for loss of a motor or prop is miniscule.
The number that crash because owners fly them into things is huge.

Labroides Posted at 2017-7-16 16:00
No ... just the same issues.
It might be possible for a lightweight, purpose built drone to do that but it's a very different matter for a Phantom with enough battery for 30 minutes flying time.
Power to weight is a huge factor in the issue.

OK man, sure, your right. No proof, but your still right.

Mark The Droner Posted at 2017-7-16 12:46
Actually I have seen that vid.  I just forgot about it.  Well done.

Thank you kindly Sir.

It is not as stable and there would be low payloads

x-acto Posted at 2017-7-28 03:16
It is not as stable and there would be low payloads

I think just getting it to the ground a little slower than terminal velocity would make me happy. They can do it and they dont.

Duchunter Posted at 2017-7-28 04:32
I think just getting it to the ground a little slower than terminal velocity would make me happy. They can do it and they dont.

It may be a case of how much would you be willing to pay to license this piece of software in DJI products, it's very likely copyright protected. Besides how would it behave in the real environment where there could easily be wind factors to be taken into account ?

Quite likely that gimbal/camera would take some damage if coming down from 200 feet in a 20 mph wind.

Aardvark Posted at 2017-7-29 16:07
It may be a case of how much would you be willing to pay to license this piece of software in DJI products, it's very likely copyright protected. Besides how would it behave in the real environment where there could easily be wind factors to be taken into account ?

Quite likely that gimbal/camera would take some damage if coming down from 200 feet in a 20 mph wind.

Your probably right but I imagine its gonna do more damage falling out of the sky. If they could just make it fall a little slower and give it a better chance of surviving I would be happy. I just think that they could do more than nothing. If for no other reason than to give people more time to get away from it. DJi wants to dictate all kinds of "safety" measures so why not have one that people would actually like to have? They only dictate safety measures that protect them from liability or that if not implemented could cause drones to be banned outright. There more than willing to protect themselves but getting a drone to the ground safely after a prop/motor failure doesnt benefit them in the least and thats why they dont use this technology. Take me for example, I lose a prop in flight, my drone is lost, now dji is $800 richer. If my p4 had this teck I wouldnt have needed to buy another p4. Thats a win for DJI.

Duchunter Posted at 2017-7-29 17:01
Your probably right but I imagine its gonna do more damage falling out of the sky. If they could just make it fall a little slower and give it a better chance of surviving I would be happy. I just think that they could do more than nothing. If for no other reason than to give people more time to get away from it. DJi wants to dictate all kinds of "safety" measures so why not have one that people would actually like to have? They only dictate safety measures that protect them from liability or that if not implemented could cause drones to be banned outright. There more than willing to protect themselves but getting a drone to the ground safely after a prop/motor failure doesnt benefit them in the least and thats why they dont use this technology. Take me for example, I lose a prop in flight, my drone is lost, now dji is $800 richer. If my p4 had this teck I wouldnt have needed to buy another p4. Thats a win for DJI.

Something to consider, at least in the first clip you showed, is that all the quads in that demo are built for inside flight, no camera or other payload and are all controlled from a central computer, so there is nothing much that they have in common with one of our aircraft. In a little aircraft like those, cutting two motors in flight and relying on the remaining two might be recoverable, but not on a larger aircraft carrying a camera.

Note that when he cut the props, he cut off both blades on two diagonally opposite props. What happens if he did it to two adjacent props? The answer is it would crash to the ground. It is an interesting demonstration, but weighted in favour of success.

'Why has DJI not incorporated this technology in its products? Is it simply that failures sell more drones? I really dont see any other reason for it.'

It could very well be because they tried to do this and found it did not work. There is equally a case that says if DJI had managed to get a failsafe mode working, they would have one of the biggest marketing advantages over any other commercially available aircraft, because no commercially available consumer level drone out there has such a feature.

' They could add a small backup power supply for gps locating after a crash, but they dont. They could do an onboard self susstained tracker, but they dont.'

How about this. Set up a poll on here to ask how many people have successfully used a separate tracker to locate and recover their aircraft? I am pretty certain you will find the number is quite low, most people who have a crash know exactly where it is or was, and if that is the case, why spend money on a feature that is hardly used.

Duchunter Posted at 2017-7-16 12:30
https://www.youtube.com/watch?v=bsHryqnvyYA
Here ya go.

10 seconds. is that a controlled flight with three propellers? 1 0   s e c o n d s...

Geebax Posted at 2017-7-29 21:17
Something to consider, at least in the first clip you showed, is that all the quads in that demo are built for inside flight, no camera or other payload and are all controlled from a central computer, so there is nothing much that they have in common with one of our aircraft. In a little aircraft like those, cutting two motors in flight and relying on the remaining two might be recoverable, but not on a larger aircraft carrying a camera.

Note that when he cut the props, he cut off both blades on two diagonally opposite props. What happens if he did it to two adjacent props? The answer is it would crash to the ground. It is an interesting demonstration, but weighted in favour of success.

Also, he did not cut the propblades all the way to the hub. He left some lenght of blade, and by revving up those two motors he might have achieved enough lift to sustain the aircraft, but probably not enough reaction  to balance the yaw...

Apparently watching one Youtube video is all it takes to become a certified Aeronautical Engineer these days.

Antonio76 Posted at 2017-8-3 12:10
Also, he did not cut the propblades all the way to the hub. He left some lenght of blade, and by revving up those two motors he might have achieved enough lift to sustain the aircraft, but probably not enough reaction  to balance the yaw...

If it will fly for 10 seconds it will fly for 10 minutes. Clearly you didnt watch the second video.

Duchunter Posted at 2017-8-3 12:27
If it will fly for 10 seconds it will fly for 10 minutes. Clearly you didnt watch the second video.

Oh, I didn't watch the second video, did I ? How could I have timed the flight otherwise, pray tell? And why limit it to 10 minutes, if it can fly ten minutes it certainly can fly for an hour...

Antonio76 Posted at 2017-8-3 12:34
Oh, I didn't watch the second video, did I ? How could I have timed the flight otherwise, pray tell? And why limit it to 10 minutes, if it can fly ten minutes it certainly can fly for an hour...

What exactly is your problem?

Duchunter Posted at 2017-8-5 08:33
What exactly is your problem?

LOL, if you think that I have a problem, then maybe you have a problem...

Antonio76 Posted at 2017-8-5 08:55
LOL, if you think that I have a problem, then maybe you have a problem...

Alrighty then.