if you're of a certain age you'll get the reference....

  So, Sunday I was working through the modes, starting with Gesture, which worked pretty neat.  Got some nice pictures and it works as advertised.  I'm sure I looked pretty silly walking around with my pet drone following me at about 20 feet, occasionally flashing the two-handed "box" gesture.  But like I said, it worked exactly as expected.

  Next up, I tried TapToFly mode and I tapped to fly in a general direction, which unfortunately led it directly through a tree.  It was pretty obvious where it was going so I tried gaining altitude to go over the tree but the mavic seemed determined to hit it.  Since the tree didn't have any leaves I feared it wouldn't trigger obstacle avoidance so all I could do was watch it get tangled in the branches, hanging up about 30 feet above the ground.  Of course as the propellers thrashed the controller was telling me about neat things about how I'm probably frying one of my engines, etc.  Eventually it exited weed wacker mode and just hung out, red light flashing forlornly.  
  Fortunately home doubles as a tree farm so there was no shortage of tools or ladders.  The only way I could get close to the drone was with a 16 foot step ladder with a 12 foot pole pruner, of the manual, not chain saw type.  I was able to bounce the branches below into the branch it was stuck on but I still couldn't get it free.  So disregarding the safety recommendations on the ladder I got a little higher and it fell out of the tree.  Miraculously I was able to grab it on the way down without falling off the ladder.  
  
  I had to replace all four blades, and now I've got a couple more spares on order.  I took it up for a quick flight to see what kind of damage was inflicted.  It seemed to fly well and sounded more or less normal.  Are there any diagnostics I can run to make sure all the motors are functioning normally?  Anything to listen or watch for if the bearings in the motor were compromised?  The preflight checklist is a place to start but a little more detail would be nice.  

  So, the core of the issues was user error, but the obstacle avoidance doesn't seem to identify bare branches as an obstacle.  What are the parameters for the obstacle avoidance?  Is there a minimum object density that it avoids?  For instance, had the tree been fully foilaged would the obstacle avoidance have kicked in?  How solid does an object need to be for obstacle avoidance to function.  In the tapfly tutorial video it actually shows obstacle avoidance working, avoiding a branch with leaves on it.  I'm sure it's all tied into algorithms which are tied into input from the sensor unit.  Eventually the algorithms will be updated and refined to keep us idiots out of the trees.  What's the functional distance for the front sensor?

  So, what's a proven technique everyone uses to avoid catastrophe when you see it coming?  Hit RTH?  Is there an "Omigod, we're all gonna die mode" which would cause the craft to dump momentum and hover immediately?  Between glare and inexperience I didn't see a panic button of any type which I could have hit to avoid the tree.  Flight logs are uploaded if DJI wants to check things out.

Note to self :  Never Tap to Fly towards a tree with no leaves.

BTW, isn't there a pause/ cancel button on the controller?

Wandering Cloud Posted at 2017-1-17 09:52
Note to self :  Never Tap to Fly towards a tree with no leaves.

BTW, isn't there a pause/ cancel button on the controller?

I need to triple check that.  It was extremely bright so there was a lot of glare on the ipad I was using with the DJI Go 4 app, my photograde prescription lenses had fully darkened, so I must have missed it if it was there.  Chalk it up mainly to PEBCAK.  

jayh410 Posted at 2017-1-17 10:51
I need to triple check that.  It was extremely bright so there was a lot of glare on the ipad I was using with the DJI Go 4 app, my photograde prescription lenses had fully darkened, so I must have missed it if it was there.  Chalk it up mainly to PEBCAK.

Simply press pause on the remote.

Wandering Cloud Posted at 2017-1-17 09:52
Note to self :  Never Tap to Fly towards a tree with no leaves.

BTW, isn't there a pause/ cancel button on the controller?

Yep, pause button on the controller and I'd be touching it almost any time I was using an automated mode.

As for Tap-Fly, I haven't tried it yet but wouldn't try it unless I was in the middle of a large open space with more open space where I was tapping to fly.  Just my thoughts.  Glad it seems to have survived with just prop damage.

'Of course as the propellers thrashed the controller was telling me about neat things about how I'm probably frying one of my engines, etc.  Eventually it exited weed wacker mode and just hung out, red light flashing forlornly.'

- very amusing description  

I've avoided most of the intelligent flight modes so far, as I want to test them in a safe place first and be sure that I can re-take control if something goes pear-shaped; and I want to make sure that bail out becomes second nature for me.

I think that's exactly what Pause was designed for, but it's one thing to know it and another for it to become second nature in a moment of crisis (at least for me).

BuzzCut Posted at 2017-1-17 14:01
'Of course as the propellers thrashed the controller was telling me about neat things about how I'm probably frying one of my engines, etc.  Eventually it exited weed wacker mode and just hung out, red light flashing forlornly.'

- very amusing description  

gotcha, need to condition those reflexes to go directly to the pause-button, do not pass go, do not collect 200$.  I'm primarily focused on the app and I use a holder I got from etc which I like a lot, but it does visibly obscure the Pause and 5D(?) button so of course, out of sight, out of mind.  

  Time to reread the users manual and also take a better look at the dji go 4 app.  Thanks for the advice.  

  For what it's worth, here's a front view of the ipad holder I'm using

jayh410 Posted at 2017-1-17 18:59
gotcha, need to condition those reflexes to go directly to the pause-button, do not pass go, do not collect 200$.  I'm primarily focused on the app and I use a holder I got from etc which I like a lot, but it does visibly obscure the Pause and 5D(?) button so of course, out of sight, out of mind.  

  Time to reread the users manual and also take a better look at the dji go 4 app.  Thanks for the advice.  

Nice setup!

I prefer just to wedge my iPad Mini into the controller arms, and it does have the advantage of being able to see the pause button, but I think your setup will work just fine too once you have that muscle memory down.  It'll no doubt become second nature.