So I was out flying this afternoon, brought back the Mavic to about 30 ft off the ground, made sure I was in GPS mode (NOT SPORT), started to head straight towards myself and realized too soon that the Mavic was drifting slightly to the right.  Before I could correct it, SMACK, right into a tree.  Here's the last image before it hit.  Why the heck did the Vision Posiitioning system not pick this up???  I also had made sure all the vision positioning was on.

I'm so distrought right now... All I've been reading are crazy repair costs for people without the DJI Care...

sure seems like it should have seen that. but probably would have crashed anyway when it goes up, it would have just hit the branches above.or if it tried to go around might hit the smaller branches, the sensors do not work with small things.

That sucks.  You weren't in an intelligent flight mode or using RTH so it should have just come to a halt vs. rising using the default settings, no?

Surprised it didn't see it unless it was an outer branch, but unfortunately these things aren't bulletproof, rather a helpful aid in most circumstances.

VPS is not full-proof. It has problems with small branches, buy the time it "sees" the tree it's to late.

BuzzCut Posted at 2017-1-23 09:24
That sucks.  You weren't in an intelligent flight mode or using RTH so it should have just come to a halt vs. rising using the default settings, no?

Surprised it didn't see it unless it was an outer branch, but unfortunately these things aren't bulletproof, rather a helpful aid in most circumstances.

I was in GPS mode which is the standard operating mode.  No other intelligent flight mode activated... Just heading straight home.  I must have gone through the flight log and settings about 100 times confirming everything I said.

I understand that the vision positioning won't pick up wires and thin branches but this is the friggen trunk of the tree!

R&L Aerial  Posted at 2017-1-23 10:20
VPS is not full-proof. It has problems with small branches, buy the time it "sees" the tree it's to late.

I understand its not full-proof but you see the picture right? its not just a branch.. it takes up almost 1/3 of the frame!

I've seen a lot of their videos showing how the VPS works and if it did as advertised then I would be out flying right now.

I'm more wondering if there was a defect or if this REALLY is a limitation.

Have you taken the plastic film from the forward sensors. My new mavic had these to protect the lens during shipping.

Almost hit my shed while testing the avoidance system. It appears to use the two cameras to triangulate the distance to an object, to do this it needs two good images to be able do this. It also needs a good sensor calibration! I have fair bit of optical measurement and autonomous positioning experience and good contrast is key to success, the system has limitations and poor light is one of them.

If the lighting is low, it will not work.  That is stated in the manual.  Low light conditions do not allow for the front sensors to work properly.  In the photo you attached, it looks as though it is dark outside and not good lighting.  The other extreme is they tend to stop the aircraft in mid flight if flying into direct sunlight...it don't like that either.

Sorry for your loss, I have had some of my aircraft sent in for repair and have never had any major issues...sometimes it just takes them a long time to even look at it once they get it.  Now maybe a bad time because all of the Christmas gifts and people have accidents and trying to send them in for repair.  Just have patience with them, they will pull through for you.

Daley Posted at 2017-1-23 10:28
I understand its not full-proof but you see the picture right? its not just a branch.. it takes up almost 1/3 of the frame!

I've seen a lot of their videos showing how the VPS works and if it did as advertised then I would be out flying right now.

From the picture it looks like low light, OA will slow down aircraft from 15 meters out if it's not slowing down it's not seeing obstacle, you would also be receiving warnings how fast were you travelling , you also said aircraft drifted into the tree , drifted sideways forward backwards ?? .
You can replay your flight on the app or post logs here. Just upload to this address and post here. http://www.phantomhelp.com/LogViewer/Upload/
You should also sync your flight to dji cloud.
Sorry to hear about your crash , hope you get sorted , good luck.

Sorry for your loss but that is why we stress on newbies to read and read and read the manual. Also practice, practice and practice before using all kind advanced features.

From experience I would add bright surfaces like siding. I tried to test it on a light beige siding of my house and it did NOT stop but I was under it looking to see how far and stopped it in time.

I would also add side detection only work in Beginner mode.

As ProQuad said, good lighting, good contrast, no small thin objects and for God sake guys, resist the urge of trying to test the limit of the machine it is there to help and no one will guarantee 100% RESULTS!


"Protect animal population. Spayed or Neutered? and License your Pet!"

I'm sorry for your crash, it may have been from low light but send the aircraft in for repair and the flight data analysis can determine it.
I can review the flight to see if I see anything out of the ordinary. Sync your flight records and provide your email and I'll take a look.

Buzzyone Posted at 2017-1-23 10:56
Almost hit my shed while testing the avoidance system. It appears to use the two cameras to triangulate the distance to an object, to do this it needs two good images to be able do this. It also needs a good sensor calibration! I have fair bit of optical measurement and autonomous positioning experience and good contrast is key to success, the system has limitations and poor light is one of them.

" good contrast is key to success, the system has limitations and poor light is one of them. "

This ^^^ !!
Very poor light level in the photo, 1st thing i thought when i seen it.
Its a no brainer.

Ginter Grey Posted at 2017-1-23 10:56
Have you taken the plastic film from the forward sensors. My new mavic had these to protect the lens during shipping.

Yes I made sure those were removed from day one

Bent Kangaroo Posted at 2017-1-23 15:29
" good contrast is key to success, the system has limitations and poor light is one of them. "

This ^^^ !!

This was in full sunlight in the middle of the day.  I'm not sure where the picture came from since I was taking a video up until the crash.  Here's an extract from the last moment from the video.
And now that I really think about it... I never stoppped the video from recording but the video stops 3 seconds before the crash.  The crash caused the battery to eject.  The picture that I shared is the one the is automatically taken from the aircraft for the aircraft logs.  Is it a coincidence that the aircraft took that picture right before the crash?  Or did it disable the video from recording so it could take the picture because it sensed an impact within a certain distance?  Also why is the picture in black and white while the video is in color?

hallmark007 Posted at 2017-1-23 11:29
From the picture it looks like low light, OA will slow down aircraft from 15 meters out if it's not slowing down it's not seeing obstacle, you would also be receiving warnings how fast were you travelling , you also said aircraft drifted into the tree , drifted sideways forward backwards ?? .
You can replay your flight on the app or post logs here. Just upload to this address and post here. http://www.phantomhelp.com/LogViewer/Upload/
You should also sync your flight to dji cloud.

Thanks.. I hope I can figure something out with it too.  It still flies but the camera gimbal is busted...shows live feed and allows videos/pictures but it's unusable in flight.

My maximum speed was 20mph from the log.  Being in GPS mode it won't let you go faster so the sensors stay activated.  I did not receive any speed warnings.  The drifting was normal.  If you put the right stick all the way forward the aircraft won't go exactly straight, it will probably drift left or right and you will have to make minor adjustments to keep it on track.  I wasn't correcting enough obviously lol.

Daley Posted at 2017-1-23 16:03
This was in full sunlight in the middle of the day.  I'm not sure where the picture came from since I was taking a video up until the crash.  Here's an extract from the last moment from the video.
And now that I really think about it... I never stoppped the video from recording but the video stops 3 seconds before the crash.  The crash caused the battery to eject.  The picture that I shared is the one the is automatically taken from the aircraft for the aircraft logs.  Is it a coincidence that the aircraft took that picture right before the crash?  Or did it disable the video from recording so it could take the picture because it sensed an impact within a certain distance?  Also why is the picture in black and white while the video is in color?

That picture looks like it's in color to me. I can see the grass, it's green.  
Also, if it were one branch, and that was small and thin enough then it probably wouldn't have picked that up. Was it cloudy outside? It could've been low light level due to clouds.
I have noticed when flying mind around that I tend to hit the video record and the camera shutter button without even realizing it. Those two buttons, for me, or in a position where I put my hands and fingers on the remote, and without even thinking about it I touch those two buttons and will either start and stop recording or take several photos without realizing it. That may have been the case with you as well.
I don't think DJI has come up with an algorithm to detect a photo right before I crash. Possibly future updates but I highly doubt it at this point.
Hope this is helped more in your crash.

well my issue is a little different, I was in beginner mode just getting used to flying it. I took off like normal and then it went straight backwards and slammed into my house crashed and broke the gimble off and scratched the mavic and blades all to pieces.

I have only had this a month what a kick in the teeth 1000 dollars down the drain.  I do not know what the warranty is on these I am sure none in a crash but what if the crash was not my fault and it just took off on  me. I have waited for years to buy a drone and then decided on this and waited 2 months to get it only to have my wife tell me what a waste of money, maybe DJI will step up and replace it. {:4_157:}

I crashed my car the other day and im hoping Ford will give me a brand new one.

I should have had insurance but i couldnt be bothered. I hope they give me a new one because i dont think it was my fault seeing i was only in 1st gear.
Im afraid you are going to need a better story backed by flight logs to convince some people.

ProQuad Posted at 2017-1-23 18:01
That picture looks like it's in color to me. I can see the grass, it's green.  
Also, if it were one branch, and that was small and thin enough then it probably wouldn't have picked that up. Was it cloudy outside? It could've been low light level due to clouds.
I have noticed when flying mind around that I tend to hit the video record and the camera shutter button without even realizing it. Those two buttons, for me, or in a position where I put my hands and fingers on the remote, and without even thinking about it I touch those two buttons and will either start and stop recording or take several photos without realizing it. That may have been the case with you as well.

I wonder if the vision positioning sensors record pictures, kind of like how the one for landing does to return to the same spot.

And there definitely wasn't a thin branch... As I looked up I caught the last 2 seconds of its demise hitting 20mph into the trunk of the tree

For yours I would try to get ahold of DJI Ken and have him review the flight log.  If it was a manufacturing issue then its covered.. but the hard point is proving that.  Most of the time is user error and unfortunately we have to eat the cost to have it repaired.  Very expensive lesson learned but to make you feel better we have all done it.

Daley Posted at 2017-1-23 16:14
Thanks.. I hope I can figure something out with it too.  It still flies but the camera gimbal is busted...shows live feed and allows videos/pictures but it's unusable in flight.

My maximum speed was 20mph from the log.  Being in GPS mode it won't let you go faster so the sensors stay activated.  I did not receive any speed warnings.  The drifting was normal.  If you put the right stick all the way forward the aircraft won't go exactly straight, it will probably drift left or right and you will have to make minor adjustments to keep it on track.  I wasn't correcting enough obviously lol.

I looked at your flight record from the GO app and I cannot determine a cause. When you sent the aircraft in for repair they will analyze the flight data recorder and be able to tell you more about the obstacle avoidance.

Daley Posted at 2017-1-23 16:14
Thanks.. I hope I can figure something out with it too.  It still flies but the camera gimbal is busted...shows live feed and allows videos/pictures but it's unusable in flight.

My maximum speed was 20mph from the log.  Being in GPS mode it won't let you go faster so the sensors stay activated.  I did not receive any speed warnings.  The drifting was normal.  If you put the right stick all the way forward the aircraft won't go exactly straight, it will probably drift left or right and you will have to make minor adjustments to keep it on track.  I wasn't correcting enough obviously lol.

"The drifting was normal.  If you put the right stick all the way forward the aircraft won't go exactly straight, it will probably drift left or right and you will have to make minor adjustments to keep it on track.  I wasn't correcting enough obviously lol."

Actually, I wouldn't really consider that normal. If it's in GPS mode and properly calibrated, I expect my Mavic to go in a straight line when I press forward. How much drift are you talking about here?

mikemcc Posted at 2017-1-23 18:30
well my issue is a little different, I was in beginner mode just getting used to flying it. I took off like normal and then it went straight backwards and slammed into my house crashed and broke the gimble off and scratched the mavic and blades all to pieces.

I have only had this a month what a kick in the teeth 1000 dollars down the drain.  I do not know what the warranty is on these I am sure none in a crash but what if the crash was not my fault and it just took off on  me. I have waited for years to buy a drone and then decided on this and waited 2 months to get it only to have my wife tell me what a waste of money, maybe DJI will step up and replace it.

Well I don't know if it's fortunate for you or unfortunate, but dji can tell by your logs if you pushed your right stick down causing the aircraft to fly backwards, or the aircraft malfunctioned ,
Good luck..

Very thin tree, sensors are just missing it probably.

Jason Lane Posted at 2017-1-24 01:30
"The drifting was normal.  If you put the right stick all the way forward the aircraft won't go exactly straight, it will probably drift left or right and you will have to make minor adjustments to keep it on track.  I wasn't correcting enough obviously lol."

Actually, I wouldn't really consider that normal. If it's in GPS mode and properly calibrated, I expect my Mavic to go in a straight line when I press forward. How much drift are you talking about here?

my only input was nose down to 100%.  Probably ended up 10 ft to the right after about 100ft of flight

If you look at the colour of the bark of the tree, it sort of blends with the ground below. We use our brain to distinguish the tree from the ground, but the mavic depends on a pattern recognition algorithm which in most cases would fail if the object in question is of the same colour as the background. It's a bit like if you wear a green shirt for a chroma key video take with a green screen as the background. It is impossible for the software to distinguish between the shirt and the background. Whatever the reason, I hope the damage is not too severe and wish ur Mavic a speedy recovery.

mikemcc Posted at 2017-1-23 18:30
well my issue is a little different, I was in beginner mode just getting used to flying it. I took off like normal and then it went straight backwards and slammed into my house crashed and broke the gimble off and scratched the mavic and blades all to pieces.

I have only had this a month what a kick in the teeth 1000 dollars down the drain.  I do not know what the warranty is on these I am sure none in a crash but what if the crash was not my fault and it just took off on  me. I have waited for years to buy a drone and then decided on this and waited 2 months to get it only to have my wife tell me what a waste of money, maybe DJI will step up and replace it.

I wrecked my P4 after 6 months (hot dogging, totally my fault) ripping off one landing gear, screwed up compass and gimbal - flew into a tree at about 30mph, recovered and flew out but it was toast.  It would fly but not in any manner I wanted to fly.  The total bill was around $180, not too bad.  If you were in beginner mode and it just flew off, I would send the logs in to DJI to analyze.  They will replace it if it was the fault of the aircraft.   

DJI-Ken Posted at 2017-1-23 22:13
I looked at your flight record from the GO app and I cannot determine a cause. When you sent the aircraft in for repair they will analyze the flight data recorder and be able to tell you more about the obstacle avoidance.

Ok thanks for looking Ken.  Any idea why the picture uploaded to the flight plan was in black and white while the main camera video was in color?

enc3phalon Posted at 2017-1-24 15:52
If you look at the colour of the bark of the tree, it sort of blends with the ground below. We use our brain to distinguish the tree from the ground, but the mavic depends on a pattern recognition algorithm which in most cases would fail if the object in question is of the same colour as the background. It's a bit like if you wear a green shirt for a chroma key video take with a green screen as the background. It is impossible for the software to distinguish between the shirt and the background. Whatever the reason, I hope the damage is not too severe and wish ur Mavic a speedy recovery.

Yea I can see that now and it makes sense with your example of the green screen.  I'm thinking about t sending it in to have it repaired.  I can easily do the repair myself but the hard part is getting a camera gimbal assembly... that thing is definitely wrecked.

The Roach Posted at 2017-1-24 15:56
I wrecked my P4 after 6 months (hot dogging, totally my fault) ripping off one landing gear, screwed up compass and gimbal - flew into a tree at about 30mph, recovered and flew out but it was toast.  It would fly but not in any manner I wanted to fly.  The total bill was around $180, not too bad.  If you were in beginner mode and it just flew off, I would send the logs in to DJI to analyze.  They will replace it if it was the fault of the aircraft.

Only $180?! That sounds like a really great price.  The camera gimbal alone for the P4 is $379! I'm on the fence about sending it in because I can definitely do the repair myself if I was to buy the camera gimbal assembly from an authorized DJI repair shop but they don't have them in stock yet.

Were they able to fix your damaged camera gimbal or did they give you a new one?

What do you think I should do?  I don't want to send it in to only get an invoice that is the cost of a camera gimbal (my guess $300) plus labor to take it apart and plug it in.  I figure by then I'm halfway to the price of a new Mavic Pro.

Buffalo Trace has made me prone to speculation right now, so here goes...

1) The sensors should generally have picked this up.  Mine would have.  They're pretty sensitive and very effective.  It's a good system.  I wouldn't be shocked  if there was a level of failure in this particular case.
2) Even if there was a failure on some level it doesn't appear that you were watching the bird as closely as you should have.  It shouldn't have drifted 10 ft over the course of 100 ft unless it lost GPS.  Even if it did it meant that you were generally flying in the direction of the tree in what otherwise appears to be a fairly open area and didn't notice the drift or braked manually to stop it.

Hopefully if no obvious fault can be determined from the logs there's a compromise and you get back in the air sooner rather than later.  I wish you the best.

DJI-Ken Posted at 2017-1-23 22:13
I looked at your flight record from the GO app and I cannot determine a cause. When you sent the aircraft in for repair they will analyze the flight data recorder and be able to tell you more about the obstacle avoidance.

Don't you think its a bit strange that the stored picture in the flight log is black and white but the image taken from the main camera is in color?

Also isn't it strange that it took a picture right before impact?

BuzzCut Posted at 2017-1-24 21:49
Buffalo Trace has made me prone to speculation right now, so here goes...

1) The sensors should generally have picked this up.  Mine would have.  They're pretty sensitive and very effective.  It's a good system.  I wouldn't be shocked  if there was a level of failure in this particular case.

1) I agree.  From all the videos I have seen, the obstacle avoidance has worked flawlessly.
2) I noticed I had about 10% rudder in my control when I first started the forward run.  This accounts for the drift.  And I've learned my lesson to watch it more carefully now.... my gut was telling me to stop  while my eyes thought there was plenty of clearance from the tree.

There is no question that it was my fault that I headed directly into the tree.  I take full responsibility for that.  I'm just discussing the technology that is advertised as not working.  Whether it was under the 'contrast' limits in the technology or a fault in the system will for DJI to diagnose.  I'll update this thread when I hear back.  My guess is it will probably take a month for the whole process.  

Daley Posted at 2017-1-24 16:57
Ok thanks for looking Ken.  Any idea why the picture uploaded to the flight plan was in black and white while the main camera video was in color?

No I do not, sorry.

Daley Posted at 2017-1-24 17:10
Only $180?! That sounds like a really great price.  The camera gimbal alone for the P4 is $379! I'm on the fence about sending it in because I can definitely do the repair myself if I was to buy the camera gimbal assembly from an authorized DJI repair shop but they don't have them in stock yet.

Were they able to fix your damaged camera gimbal or did they give you a new one?

They will send you a refurb replacement.  I marked mine before I sent it in.  Didn't get the same one back.  Also, the one returned to me had a fan issue out of the box.  I can hear it hitting something on the inside.  Not bad enough to send it back but when I have onlookers they ask about the noise and get a bad taste for DJI from the get go.  Starting to become disappointed with DJI.   

The Roach Posted at 2017-1-25 15:29
They will send you a refurb replacement.  I marked mine before I sent it in.  Didn't get the same one back.  Also, the one returned to me had a fan issue out of the box.  I can hear it hitting something on the inside.  Not bad enough to send it back but when I have onlookers they ask about the noise and get a bad taste for DJI from the get go.  Starting to become disappointed with DJI.

If I could get a refurb for that price I'll be ecstatic.  Hopefully with no inherited issues like yours and some others I've read

[img]UPDATE

Opened a case for repair on 1/26 and had it at UPS by 1/27.  I live in CT and it went to the repair center for DJI in Carson, CA.  It was delivered on 2/1, the did the damage assessment and had me a quote by 2/2!  I paid right away because it was only $103!  I am so relieved... Repairs should start today if not then Monday.

Hopefully I can get it back by end of next week but so far everything has been great service from DJI.  They even paid for the shipping.  They determined the cause as pilot error which I am fine with.

There is also a link on the DJI repairs website that allows you to look at the cost of the most commonly replaced parts.  It's nice to see that they really got their part price down.. Alot of the plastic injected parts and metal formed/cast parts are only a couple of dollars.  I'll update again when I get the Mavic back.[/img]

The Roach Posted at 2017-1-25 15:29
They will send you a refurb replacement.  I marked mine before I sent it in.  Didn't get the same one back.  Also, the one returned to me had a fan issue out of the box.  I can hear it hitting something on the inside.  Not bad enough to send it back but when I have onlookers they ask about the noise and get a bad taste for DJI from the get go.  Starting to become disappointed with DJI.

This is what concerns me about exercising DJI Care Refresh - you are sent someone else's rejected, problem drone, and someone else who uses their refresh is sent your problem drone. This is outlined in the details of the DJI Care agreement but support won't directly tell you that -

PimpDawg Posted at 2017-2-3 08:53
This is what concerns me about exercising DJI Care Refresh - you are sent someone else's rejected, problem drone, and someone else who uses their refresh is sent your problem drone. This is outlined in the details of the DJI Care agreement but support won't directly tell you that -

I didn't purchase DJI Care so this is all out of my pocket.  I'll let you know if I get the same drone back.

Daley Posted at 2017-2-3 09:27
I didn't purchase DJI Care so this is all out of my pocket.  I'll let you know if I get the same drone back.

You will not get the same drone back.  It will be a refurb.