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I don't need no stinking Compass, Help!

Discussion in 'Inspire 1 Discussion' started by Pete Rosas, Apr 9, 2015.

  1. Pete Rosas

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    Gentleman, I have a compass calibration question. I am trying to use the I1 to inspect the inside of an all metal building with lots of large magnetic fields. I have several successful flights outside but when I move in the building I get the “Compass needs calibrated” warning and it will not let me arm the speed controllers and fly. I have armed the speed controllers outside flew into the building and then the “Compass needs calibrated” warning appears during flight, I did not land but continued to fly reaching altitudes of about 5 stories inside the building and had no problems. Then landed and could not take off again. Long story short I need to be able to fly without compass calibration, I know it is capable because of the test so I need to find a way to bypass this step and do all the flying manually. Can anyone help?
     
  2. Scotflieger

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    Without a calibrated compass you have no directional stability. DJI state that you should avoid large areas of metal and strong magnetic fields. If you are unable to calibrate the compass inside the building then I suggest you take their advice.
     
  3. Kilrah

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    It is not possible. It will not take off with a compass error whatever you do, even if it is indeed not actively used in ATTI mode.

    You should be able to calibrate the compass inside, even if the calibration will be useless at least it should let you takeoff from the place you calibrated it.
    Don't forget to recalibrate next time you're outside though.
     
  4. The Editor

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    Where are you trying to fly........Inside the Large Hadron Collider????? :p
    There must be some pretty crazy magnetic fields going on if the compass won't even calibrate!
     
  5. skylabimaging

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    The inspire is not the best survey machine...at all.
     
  6. Pete Rosas

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    Just a little clarification. I need to fly it in a giant boiler and inside the building surrounding the boiler to inspect areas that cannot be easily or too costly to put up scaffold. Just to give you an idea of the size, the open area inside the boiler is 50’ wide 75’ long and 150’ to the top. It has 4” thick steel tube walls on all sides. The building around the boiler is about the size of a city block and 30 stories tall with huge open areas. This is an electrical generation plant with a 700 megawatt output so needless to say there is no escaping the magnetic field in the building. What DJI recommends has no bearing on how it will be used in a closed controlled environment. All safety precaution will be and have been used to keep personal away from harm’s way. With that said I have not had any success getting the compass to stay calibrated in the building. All the control of the aircraft will be strictly from me the pilot because obviously there is no chance of outside support via satellite or otherwise. All the pilot assistance will be from the internal gyros and accelerometers. I know it can do it because of the test when I flew from outside to inside the building with in close proximity to the generator without issues. The compass needs calibration warning was flashing for virtually the entire flight. But like I said once I landed it would not let me take back off. I need to be able to arm the speed controllers and fly without compass calibration.
     
  7. Josh Hanson

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    Damn.....Good luck with that!
     
  8. Phatzo

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    would unplugging the compass solve the problem? might be a dumb question at the moment but being able to turn it off in the app would be nice for exactly those kind of jobs.

    let me know if I am talking bullsh*t :D
     
  9. Kilrah

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    Nice, would love to see that!

    But yeah, your observation and what you did is all you can do to get it to work from what we know. Either take off outside, or try calibrating inside hoping it will accept that calibration long enough to let you start the motors. Once they're started no problem and the warning in flight isn't an issue in this case.

    You can maybe try disconnecting the compass indeed but I doubt the FC will want to startup wihout it.
     
  10. The Editor

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    Although we do not know for sure, I think an unplugged compass would be seen as 'no data' from the compass module and would be treated the same way 'bad data' and keep the Inspire grounded with no response from CSC.

    As stated above, I think the 'workaround' in this case will be to start up outside and then fly in. Assuming you have TB48's this should give you a comfortable 18 mins in the air (probably a little more since there will be no corrections being applied by the FC for drift etc).
    Fly for 18 mins, land, rinse, repeat..... :)