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Hit the tree and crashed

Discussion in 'Phantom 2 Vision Discussion' started by PropsPete, Mar 24, 2014.

  1. PropsPete

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    Hi all,

    I thought that this would never happen to me because I'm so careful with my flying. This was my 12th flight and I was practicing different maneuvers. Beautiful weather with almost zero wind.

    I was flying at my backyard and my neighbors have some tall birch trees near our border. I was making circles around when suddenly there was a gust pushing my lovely bird towards the trees. I couldn't do anything than watch when my P2V hit the branches (at 12 feet) rolled over and plunged down. Hit the ground pretty hard BUT bounced back in to air. I was able to recover the control for a brief moment but then it hit our apple tree and came down for a final stop.

    Camera was hanging only by a zip tie with UV filter cracked. Some scratches here and there. All props had some damage also. Main body seem to be ok and I also tested later inside that camera is still working and motors rolling.

    So, I probably need to open up the main body and check that everything is ok in there? Also need to calibrate the compass? Anything else?

    Cheers,
    Pete
     
  2. Pull_Up

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    After a good thump I'd do an IMU calibration before next flight, personally. I've had one go a bit nuts on me after a drop from 4ft so took it home and ran the IMU call and it for beautifully after that.

    Compass should be fine unless you use magnetised tools to open the shell, but no harm to calibrate that provided you do it in a good location as per usual advice.
     
  3. Pull_Up

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    Oh and never trust trees. They will move into your path when you're not looking...
     
  4. RamDez

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    AND BUSHES .............. they sneak up when you least expect it ah tell you.
     
  5. SlackerATX

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    I took a spill like that and the phantom wasn't flying nearly as well. I inspected it best I could and finally noticed one of the arm was tweaked so the prop was not level. Just about 3mm off but it makes a big difference. Also one of my motors seems to be a lot stiffer than the other three. I just spin the motor and there more friction on that one. I'm not sure how much of a problem that is, but I'm considering swapping out the motor as well.
     
  6. EMCSQUAR

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    We need to report these trees to the FAA...
     
  7. PropsPete

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    One thing is for sure - I'm going to watch those trees more carefully in future. But I guess this had to happen sooner or later.

    I opened the P2V and everything seem to be in place. No loose connections or anything. There is something loose in the camera like grind of sand. Didn't open it because it's still working.

    I calibrated (advanced) the IMU but first couple times it gave me 'temperature too high try later' warning. Temperature couldn't be high because I had just turned it on. After those warning I changed the battery to one I had not used when crashed. Then IMU calibration worked. Might be just coincident that changing the battery made the difference.

    Fly safe everyone!
     
  8. Pull_Up

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    Sorry, I forgot to say the "too hot" thing is a known bug, just ignore and click through and it should do it anyway.
     
  9. PropsPete

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    Had my first flight after the crash.

    I did IMU and compass calibration successfully and changed all four prop. Now it doesn't seem to hover like it did. It's shaking a bit now and then and motors are doing some extra work when it's shaking. I'm not sure if it's shaking due some light breeze but it was definitely not windy. So at least it seem to be more sensitive even to light breeze.

    Could this be some sort of motor damage? One motor feels a bit stiffer than the others. What else might be failing?
     
  10. Pull_Up

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    There might be some crud in the suspect motor. Might be worth opening the motor up and giving it a good look inside, especially if it feels differently to the others. With the shell open it's just a case of undoing the 4 motor screws, taking the e-clip off (carefully, they have a habit of never being seen again if they ping off!) then pulling the motor open. There should be enough slack that you don't have to unsolder it to do this if you don't want to - just watch out for straining the solder joints.
     
  11. PropsPete

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    Thank you Simon.

    If I need/want to change any of the motors have anyone upgraded them to the Tiger MN2214? Would it be worth it? I just want to get my bird back in the sky because I have ordered the Rotorpixel Gimbal (#404) and now my P2V is broke somehow.

    Lot of things in my mind right now. Should I buy a new P2V or plain P2 because I already have iPad and GoPro 3 black? Should I replace the motors and will it fix the shake. Or do I need to replace the body? Might it be some other component failing, IMU, GPS? Will my P2V camera continue to work even though there is something loose inside?

    Why did I hit the tree :cry:
     
  12. Pull_Up

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    Trees are evil, nothing we can do about that. I would go systematically - you've identfied one motor that appears to be misbehaving. You can either take it apart and attempt to clear the issue, or for peace of mind just buy a replacement DJI motor (make sure you get the correct handedness to match the bad one) and fit it in. Then if the issue is still there you can trouble-shoot further. The fact that one motor is feeling different would tend to suggest there's a good chance that's the culprit...
     
  13. jimdenburg

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    You said you damaged all four props in the crash. Did you check the balance on the replacements? If they're out of balance you will get a shaky craft.
     
  14. PropsPete

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    Yes, I had a new set of balanced props. P2V is shaking only randomly. It might be related to certain level of throttle which would refer to motor problem.

    EDIT: Ordered 4 new motors and bullet connectors also. I'll solder those connectors between ESC and motor to speed up the change in future.
     
  15. PropsPete

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    I have now changed two motors after the crash. Both on 'front' arms where I had clear marks of impact. I was able to reduce the shakiness with this but it's still shaking sideways from time to time. Nothing major but still. There are no unusual sounds from motors.

    What might cause this irregular small shaking? It's nothing in electronics I guess. Vibration dampers, props, shell? Or one of the motors? I have tried both balanced and out-of-the-box props but the result is the same.

    I was also monitoring the motors and their shutdown and if they all stop at the same time. I changed both of those motors that stopped first. One of those new motors still stops before the others. Is this still something I should be worried about and what might be the reason for this? Faulty ESC? And what symptoms do I get when there's something wrong with ESC?
    Or am I now paranoid after the crash

    Or should I just forget this minor 'thing' and continue flying. I have now approx. 15 minutes flight time after the crash where 5 minutes with those two new motors. I have had no other problems.
     
  16. yawnalot29

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    Maybe try tweaking basic gains?
     
  17. PropsPete

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    Are there any written instructions about these gains or is it more like try and error effort?
     
  18. yawnalot29

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    There's a thread called "Let's Talk about Gain" here that has written instructions. The Assistant software also has instruction. And the behavior you describe is exactly what happen when gain is too high. In fact,the tuning instruction is to increase it until it wobble and then dial it back 10%.

    Doesn't cost you anything and can be done by you in minutes and can be reverted. So even if it's "trial & error" effort, what have you got to lose?