Obstacle Avoidance Fail

[TheRealDrew]

Well, I suck. In less than 14 days and on my 52nd minute of flight time with my new Mavic 3 Classic I flew it right into a tree and destroyed it. 3 of 4 propellers were destroyed and the Gimbal housing cracked open like an egg. Sure glad I purchased the refresh plan.

I already have a DJI Mini 3 Pro. Crashed that one once already too. But one of the big selling points for the DJI Mavic 3 was its omnidirectional obstacle avoidance. I know it's not foolproof on any drone. I especially know that now. But I'm curious to hear your thoughts on why it failed in this specific instance:

Go ahead, let me have it, but you're not going to hurt my feelings. I already know how much I suck, how my flying sucks, and what an idiot I am.

I'm disappointed that the obstacle avoidance failed, but at least now I know from first-hand experience how unreliable it is.

Just curious to hear people's thoughts on what fooled the AI in this instance. Is there any chance this was a device malfunction? Or am I 100% at fault?

Here's a link to the flight log I uploaded to phantomhelp: DJI Flight Log Viewer - PhantomHelp.com

Thanks!

Edit: Attached Flight Log from DJI RC Controller and a link to the unencrypted log on phantomhelp.

 

[Yorkshire_Pud]

What flight mode was the drone in?

 

[TheRealDrew]

What flight mode was the drone in?

Normal! I am 100% confident of that fact

 

[Yorkshire_Pud]

Normal! I am 100% confident of that fact

It will probably tell you if you replay the flight in the flight records section of the app.
The above said, why did you fly at the trees at speed?

 

[TheRealDrew]

It will probably tell you if you replay the flight in the flight records section of the app.
The above said, why did you fly at the trees at speed?

I am 100% confident it was in Normal mode because I had just switched it out of Cine mode.

It wasn't intentional. I had the drone in my line of sight and my depth perception was just off. That, and I panicked because I realized at the last minute I was going into the tree, but instead of braking like I wanted to, I tried to go up. So yeah, epic fails in every possible way.

 

[Meta4]

Just curious to hear people's thoughts on what fooled the AI in this instance. Is there any chance this was a device malfunction? Or am I 100% at fault?

To get some idea of what happened in the incident you need to post your recorded flight data.
To do that go to DJI Flight Log Viewer | Phantom Help
Follow the instructions there to upload your flight record from your phone or tablet.
That will give you a detailed report of the flight.
Come back and post a link to the report it gives you.
Or .. just post the txt file here.

And flying close to tree branches is just asking for trouble.
Obstacle avoidance will generally do a good job, but small branches and poor lighting are a problem for it.
The most effective obstacle avoidance it to avoid flying close to obstacles.
It's very hard to get into trouble when there's nothing to hit.

 

[TheRealDrew]

To get some idea of what happened in the incident you need to post your recorded flight data.
To do that go to DJI Flight Log Viewer | Phantom Help
Follow the instructions there to upload your flight record from your phone or tablet.
That will give you a detailed report of the flight.
Come back and post a link to the report it gives you.
Or .. just post the txt file here.

And flying close to tree branches is just asking for trouble.
Obstacle avoidance will generally do a good job, but small branches and poor lighting are a problem for it.
The most effective obstacle avoidance it to avoid flying close to obstacles.
It's very hard to get into trouble when there's nothing to hit.

Post updated with raw flight log and here's the link to phantomhelp logviewer: DJI Flight Log Viewer - PhantomHelp.com

And all valid points on how to not have this happen again. I've learned my lesson.

 

[Meta4]

Post updated with raw flight log and here's the link to phantomhelp logviewer: DJI Flight Log Viewer - PhantomHelp.com

The video looks like you were heading straight for the tree at speed.
You accelerated from zero to 11.6 metre/sec with the drone tilted forward at 30° when Obstacle Avoidance slammed the brakes on hard.
OA tilted the drone back at 30° to stop it.

OA had brought the speed back to 4.5 m/s when the collision occurred at 12:11.3.
But from 12:10.7 you pulled the right stick full back and half right, just before the collision.
Your last second joystick input may have been a factor, but it's hard to tell.

 

[akdrone]

I flew into a big spruce tree once. My Mav 3 cut off a limb with a diameter about the width of my thumb and didn't even go down. I was impressed and realized how deadly the props could be. It could clearly take off a finger. Sorry your drone didn't do similarly. When I am flying in a dodgy area I tend to use my big iPad and I am sure it has allowed me to see details (wires in particular) and avoid a crash more than once.

 

[Droning on and on...]

I flew into a big spruce tree once. My Mav 3 cut off a limb with a diameter about the width of my thumb and didn't even go down. I was impressed and realized how deadly the props could be. It could clearly take off a finger. Sorry your drone didn't do similarly.

Whut, take of his nose picker? You're cruel....

 

[3rdof5]

I have not had any issues with Obstacle avoidance with my Classic other than I usually turn it off because it's too sensitive and prohibits me from flying in areas I know I can fly in. I have purposely tried to crash it and I never even get close. All in Normal Mode.
As mentioned, it's disabled in Sport mode and in low light conditions. I'm honestly not sure how you were able to crash it if everything was enabled and active.

 

[singram]

I'm honestly not sure how you were able to crash it if everything was enabled and active.

Coincidently I watched a Youtube video a few days ago regarding the top 12 mistakes you should avoid while flying. The drone in the video was even a Mavic 3 Classic! Here. I strongly suspect OP 's crash was caused by an issue discussed in the video pertaining to OA and the distance in takes to come to an emergency stop. The premise being- Mavic 3 OA is awesome and all, but its not to be 100% relied on and more to the point, even with OA enabled, the drone will not stop on a dime if you send it sticks full forward.

OP, you dont suck or anything. ALOT of people in the comments section in the video I linked have done the same thing. It dose however sound like you are overly dependent on the abilities of the drone itself and less on your own. IMO. If you send it, its your responsibility to "unsend" it, lol.

 

[3rdof5]

Coincidently I watched a Youtube video a few days ago regarding the top 12 mistakes you should avoid while flying. The drone in the video was even a Mavic 3 Classic! Here. I strongly suspect OP 's crash was caused by an issue discussed in the video pertaining to OA and the distance in takes to come to an emergency stop. The premise being- Mavic 3 OA is awesome and all, but its not to be 100% relied on and more to the point, even with OA enabled, the drone will not stop on a dime if you send it sticks full forward.

OP, you dont suck or anything. ALOT of people in the comments section in the video I linked have done the same thing. It dose however sound like you are overly dependent on the abilities of the drone itself and less on your own. IMO. If you send it, its your responsibility to "unsend" it, lol.

Well said,
The first thing I noticed with my Classic was that it's braking speed was set too low by default. Easily corrected in the settings.
That being said, when my OA is enabled and I'm anywhere near obstacles, I can't approach them fast enough to have to worry about braking speed. I really wish there was a OA sensitivity setting.

 

[singram]

Well said,
The first thing I noticed with my Classic was that it's braking speed was set too low by default. Easily corrected in the settings.
That being said, when my OA is enabled and I'm anywhere near obstacles, I can't approach them fast enough to have to worry about braking speed. I really wish there was a OA sensitivity setting.

Thanks. Very interesting, never noticed a braking speed option in the settings. I'll have to take a closer look. I do agree, OA sensitivity would be nice to play with.

Like RTH, I dont rely on OA. Like, at all. I have my OA set to bypass as opposed to break. A few months ago I about had a grabber taking off from my back deck. Upon takeoff, I navigated the drone (very safely) about 3ft above the deck railing prior to heading out over the river. However, the OA freaked out and caused the drone to suddenly raise about about 4ft up and away from the deck railing within inches of slamming into my gutter. Since then, I typically only take off or land in Sport mode only. Very odd, annoying little issue given all the awesomeness in this drone :/

 

[3rdof5]

Thanks. Very interesting, never noticed a braking speed option in the settings. I'll have to take a closer look. I do agree, OA sensitivity would be nice to play with.

Like RTH, I dont rely on OA. Like, at all. I have my OA set to bypass as opposed to break. A few months ago I about had a grabber taking off from my back deck. Upon takeoff, I navigated the drone (very safely) about 3ft above the deck railing prior to heading out over the river. However, the OA freaked out and caused the drone to suddenly raise about about 4ft up and away from the deck railing within inches of slamming into my gutter. Since then, I typically only take off or land in Sport mode only. Very odd, annoying little issue given all the awesomeness in this drone :/

I adressed this issue in another thread. OA wil definitely cause the aircraft to seek the easiest route when in bypass mode and often that route is up. Not always a good thing. I use brake mode mostly unless I'm expecting a long distance, uncontrolled RTH and I want full failsafes.

 

[Yorkshire_Pud]

That, and I panicked because I realised at the last minute I was going into the tree, but instead of braking like I wanted to, I tried to go up.

We all make mistakes, I had a situation where the reverse applied. A misjudged M2Z flight over my house's roof that was too low, braking/reversing sent it into a tree, climbing would have got the drone to safety.