It appears the phantom comes crashing down hard if one of the motors fails during flight. Is there anyway the phantom could recognize a motor has failed and then shut of the opposite motor leaving the other two motors to safely auto land? Is this even possible or are the motors not powerful enough to keep it dropping from the sky? Can a phantom hover or descend using only two motors? Planes can fly off one engine so could a quadcopter have some type of limited flight from two or three motors?

Is any company working on a way to improve the safety and flightability of a quad if one motor fails?

Google is your friend. I came across this. This is back from 2013 so why hasn't this been implemented if it really works. It's just a matter of time before one of these phantoms come crashing down possibly injuring or killing someone....

http://www.gizmag.com/quadcopter-failure-algorithm/30031/

In answer to your question "Can phantom safely land with only two opposite motors running?" the answer is NO.

In answer to you question "Planes can fly off one engine so could a quadcopter have some type of limited flight from two or three motors?"
Aeroplanes have wings for lift so you cant compare the two. Do you know the difference between a helicopter and a aeroplane ?

rdc44444@hotmai Posted at 2015-3-9 03:52
Google is your friend. I came across this. This is back from 2013 so why hasn't this been implemente ...

I think the chances of safe landing in this situation is virtual zero. The issue is the phantom not really knows when motor is not working, all it knows its side is falling, so it tries to compensate by more throttle on the falling side motor, if motor is a toast it will just get out of control in split seconds.

johnwarr@live.c Posted at 2015-3-9 04:48
In answer to your question "Can phantom safely land with only two opposite motors running?" the answ ...

Don't have to get smart with me. Of course I know the difference I was just using it as an example... again why couldn't it safely land with three motors like in the link?

Rotor blades are rotating wings...They do cause lift by passing thru the air.  That is an interesting thought about running on 2 opposing motors!

johnwarr@live.c Posted at 2015-3-9 04:48
In answer to your question "Can phantom safely land with only two opposite motors running?" the answ ...

Actually helicopters are safer then dropping like a rock, because of props would continue to spin and provide lift during fall. another good news the elevation is usually low.

Naza-PA Posted at 2015-3-9 05:07
Actually helicopters are safer then dropping like a rock, because of props would continue to spin  ...

I understand but just looking for ways it could come down in a more controlled manner. I viewed the video of you crash and your drone was doing somersaults in the air at the end. Ican imagine if it was doing somersaults at a high enough altitude it might possibly come down very hard doing some serious damage.

Full sized helicopters can use autorotate to slow their decent, but the fixed pitch blades on the phantom can not do this.
If you lose a motor or prop the phantom will crash instantly.

The problem with 2 opposing motors running would be the torque.  No way to counteract it.  It would start spinning.

oakspi Posted at 2015-3-9 05:30
The problem with 2 opposing motors running would be the torque.  No way to counteract it.  It would  ...

So I guess this is why helicopters  have the small rotor on the tail to counteract the torque? the opposite motors on the phantom spin in the same direction? If the opposite motors spun in different directions would this counteract the torque? Just curious.

Redundancy is difficult with multirotors because adding more motors (octo, hex) adds more stuff to go wrong! Those can often land with one motor out.  So you increase the chances of something happening but may save it when it does.....

The underlying issues here are safety and cost (recovery of your property). I think we are going to see these solved in various ways including:
1. Parachute systems like the new Hubsan Pro.
2. Super lightweight units like the BeBop
3. Control software that may somehow let a quad have a controlled crash...even with 3 of 4 motors working.
4. Airbags or similar.

I think another idea may be some sort of wings which spring out upon failure and cause a stronger auto-rotation, etc.

Amazingly enough, there is not a lot of research being done on this - some, but not a lot. I spoke to one of the team members on the drone staff at MIT and he and his colleagues hadn't even considered it...they are so focused on swarming and other stuff that they overlook the obvious.

rdc44444@hotmai Posted at 2015-3-9 03:52
Google is your friend. I came across this. This is back from 2013 so why hasn't this been implemente ...

Imagine if Dji came out with this firmware update. I wonder who would be brave enough to update and test it. I for one would not.

Regards

Guy

rdc44444@hotmai Posted at 2015-3-9 05:40
So I guess this is why helicopters  have the small rotor on the tail to counteract the torque? the ...

Yes, That is correct.  And the twin rotors go in opposite directions.

The parachute system would be prefect.  Perhaps it could deploy with a panic button.

rdc44444@hotmai Posted at 2015-3-9 04:53
Don't have to get smart with me. Of course I know the difference I was just using it as an example. ...

You have to consider with 2 motors out, you are developing lift from the 2 remaining motors, both being on one side.  

A man in my airplane club did land a DJI Hexcopter with one motor out.

Capt. Bill Posted at 2015-3-9 07:38
A man in my airplane club did land a DJI Hexcopter with one motor out.

1 motor out is possible, but 2 opposing motors out as in this scenario would be impossible.

It would spin and likely damage things under the craft but the landing would likely be softer than a fall from the sky

naza FC and A2 FC can handle a motor outage, provided this occurs on a hex, or octo copter.
quads are not so fortunate.

Dji have developed and currently sell a parachute system.

Eirlink Posted at 2015-3-9 07:56
naza FC and A2 FC can handle a motor outage, provided this occurs on a hex, or octo copter.
quads a ...

How does the parachute deploy?  Does it auto-deploy based on the descent speed?  

This is a pretty good explanation on how quads operate. Two motors would not work at all as the opposite motors spin in the same direction. Algorithm for a semi controlled landing softening the crash would be the best option for the phantom. Maybe future firmware update?

http://blacktieaerial.com/2014/0 ... -quadcopter-flight/

Like i wrote before in older similar threads it is possible when a motor fails on a quad to crash much softer with a special algorithm. The quad will start to spin itself like hell. Parachute Systems, for example on the new hubsan phantom like quad are deployed when the copter reaches a certain angle to the ground, beyond the 45 degree for example. Usually when motors fail the quad will turn itself on its head in the air and drop to the ground. A parachute system will help in this case.

droneflyers.com Posted at 2015-3-9 06:05
Redundancy is difficult with multirotors because adding more motors (octo, hex) adds more stuff to g ...

Thanks great info. I'm really interested in the hubsan x4 pro. 40 minute flight times according to hubsan website, 3 axis gimbal that rotates camera vertically and horizontally, built in FPV monitor, fail safe parachute, gps waypoint ground station all for $899. Sounds too good to be true but I'm extremely interested in this model if it really performs with all these features at $899. Will definately pick one up.


http://www.newsshooter.com/2015/ ... tor-for-around-500/

rdc44444@hotmai Posted at 2015-3-9 09:23
Thanks great info. I'm really interested in the hubsan x4 pro. 40 minute flight times according to  ...

This model is not 899, fully equipped its more like 1700. i think the optional parachute was 200

Daninho Posted at 2015-3-9 09:31
This model is not 899, fully equipped its more like 1700. i think the optional parachute was 200

Wow  1900 is pricey... Still 40 minute flight times, parachute, waypoint flying all which the $2800 inspire does not have. I'm excited about the drones that are going to be coming out in the next couple of years and it will be interesting to see the improvements and innovations like parachute, obstacle avoidance, talking drones, extended flight times.....yeah

rdc44444@hotmai Posted at 2015-3-9 09:39
Wow  1900 is pricey... Still 40 minute flight times, parachute, waypoint flying all which the $280 ...

Yes its interesting, the remote control looks like 600 dollar alone but the copter itself looks a bit cheap, i mean its just a 350 sized toyish copter. For that pricetag i want a bigger thing. Nobody knows how much experience hubsan has, they are new to larger quads. I hope the rumors about the DJI Phantom hexa XSIX are true, than we would have a bit of redundancy and an awesome Panasonic camera. Lets wait and see what they will release in April

Daninho Posted at 2015-3-9 09:17
Like i wrote before in older similar threads it is possible when a motor fails on a quad to crash mu ...

Drone turning upside down with motors running from a high altitude is going to make for one ugly high speed crash. ..

Daninho Posted at 2015-3-9 09:31
This model is not 899, fully equipped its more like 1700. i think the optional parachute was 200

Just curious were you found the 1700 price. No price on hubsan website and the articles I have found are saying under $1000 which I find hard to believe.
Well this website is offering it for $899. If parachute is 200 that would make it the same price as vision plus.

http://m.banggood.com/Hubsan-H10 ... opter-p-914223.html

Daninho Posted at 2015-3-9 09:44
Yes its interesting, the remote control looks like 600 dollar alone but the copter itself looks a b ...

Oh so the price doesn't include the remote... Why do they do that? Silly... Guess I'll wait and see what the final cost will be and on some reviews. Competition is good. Will keep dji on their toes. Is the phantom hexa xxl replacing the phantom vision plus or is it suppose to be another model somewhere between the phantom vision and inspire 1?

rdc44444@hotmai Posted at 2015-3-9 09:48
Drone turning upside down with motors running from a high altitude is going to make for one ugly h ...

No, the parachute is spring loaded and its triggered when the Quad reaches certain angles to the ground. The copters usually turn upside down when power is lost during a flight.

There is a youtube video about the hubsan from the CES show, the guy said 1500 dollar in april

rdc44444@hotmai Posted at 2015-3-9 09:23
Thanks great info. I'm really interested in the hubsan x4 pro. 40 minute flight times according to  ...

If you get one, will you come back to the forum and tell us more?

oakspi Posted at 2015-3-9 10:17
If you get one, will you come back to the forum and tell us more?

Yes I will but it might be awhile. I've learned to not buy anything especially a quad when it first comes out. I'm going to wait for reviews and follow some online forums to see if there are problems. It looks promising and I'm also interested to see what dji is coming out with next hopefully a whole new redesign of the phantom or a model somewhere between the phantom and inspire in the 1500 price range.

Interesting YouTube clip... The entire video is interesting but skip to the 6:30 mark
https://m.youtube.com/watch?v=w2itwFJCgFQ

love that video, pretty interesting and innovative information, thanks for sharing

gnixon2015 Posted at 2015-3-10 19:47
love that video, pretty interesting and innovative information, thanks for sharing

Quads can do anything. You must watch this...



Regards

Guy