MK Position Hold question and compass errors.

Discussion in 'Electronics' started by Charlie Cushing, Jun 20, 2015.

  1. Charlie Cushing

    Joined:
    Jan 22, 2014
    Messages:
    56
    Likes Received:
    2
    Andy, I did not do that, however, before I took off I analyzed each motor to ensure they are all on the same even field, I can definitely do what you had suggested. So what piece of equipment is not functioning correctly? A motor, prop?
     
  2. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
    Staff Member

    Joined:
    Jul 31, 2012
    Messages:
    10,366
    Likes Received:
    1,162
    Charlie: Not sure what you mean by analyzing each motor to see if "they are on the same even field?" The word "field" is not clear to me.

    What often happens is that a boom clamp is tightened with the long axis of the propeller shaft not being absolutely vertical. That's what you need to check for. Even if it's only a degree or two out of alignment that will cause the problem you are seeing.

    Andy.
     
  3. Charlie Cushing

    Joined:
    Jan 22, 2014
    Messages:
    56
    Likes Received:
    2
    Andy I took a level to each motor to ensure they are all level and then just did a flight with the file attached. Once the level was on each motor I slightly adjusted each one to make sure the motor is vertical. Does this show any improvement?
     

    Attached Files:

  4. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
    Staff Member

    Joined:
    Jul 31, 2012
    Messages:
    10,366
    Likes Received:
    1,162
    Looks better. Whaddya think, Steve, Dave?
    The test is pretty short, but certainly better than before.

    Motor1: 0.0 3.8 5.7 A Temp: 31 39 43 °C
    Motor2: 0.0 3.3 4.9 A Temp: 28 37 41 °C
    Motor3: 0.0 2.9 5.3 A Temp: 28 37 42 °C
    Motor4: 0.0 3.0 4.7 A Temp: 28 38 42 °C
    Motor5: 0.2 3.2 4.8 A Temp: 30 39 44 °C
    Motor6: 0.0 2.2 3.5 A Temp: 28 36 40 °C
    Motor7: 0.0 2.5 4.0 A Temp: 31 39 43 °C
    Motor8: 0.0 3.4 5.5 A Temp: 30 38 41 °C

    Magnet Field: 100 103 108 % (ok)
    Magnet Inclination: 65 71 80 deg
    Andy.
     
  5. Jason Smoker

    Jason Smoker Active Member

    Joined:
    Oct 23, 2012
    Messages:
    847
    Likes Received:
    67
    I think it looks ok time to throw some payload on it! :)
     
  6. Charlie Cushing

    Joined:
    Jan 22, 2014
    Messages:
    56
    Likes Received:
    2
    Here is a test flight with some weight, MOVI M5 with a Canon 5D Mark iii for an entire battery. Thoughts?
     

    Attached Files:

  7. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
    Staff Member

    Joined:
    Jul 31, 2012
    Messages:
    10,366
    Likes Received:
    1,162
    Charles:
    Sorry....I'm away from my Windows machine for a while. Have you had a look at it with MK GPXTOOL? If so, could you copy and past the motor summary from that MK_GPXTOOL creates, please?

    Thanks
    Andy
     
  8. Steve Maller

    Steve Maller UAV Grief Counselor

    Joined:
    Oct 30, 2012
    Messages:
    3,979
    Likes Received:
    807
    Charlie, now it looks better, although now you have another issue.

    Voltage : min. 19, max. 22.7 V
    Current : 0.5 57 65.1 A
    Wattage : 10 1217 1386.63 W
    Capacity: 6585 mAh

    Motor1: 0.0 8.2 10.0 A Temp: 31 48 55 °C
    Motor2: 0.1 8.1 9.7 A Temp: 28 46 54 °C
    Motor3: 0.0 6.7 7.8 A Temp: 27 45 53 °C
    Motor4: 0.0 7.1 9.1 A Temp: 28 46 53 °C
    Motor5: 0.0 6.8 7.9 A Temp: 30 46 54 °C
    Motor6: 0.0 4.9 6.2 A Temp: 27 45 53 °C
    Motor7: 0.0 5.7 6.7 A Temp: 30 47 54 °C
    Motor8: 0.1 7.7 9.4 A Temp: 28 47 55 °C

    Magnet Field: 99 106 116 % (ok)
    Magnet Inclination: 64 70 76 deg

    Errors / warnings:
    FC-Flag "LowBat" (5) occured 168 times!

    The battery voltage of 19.0V is perilously low, and I'd pay close attention to that battery now that it's been discharged below 3.2V per cell. Some feel that getting below 3.2V per cell can damage a battery. So when you recharge that battery, make sure you take note of the internal resistance and charging time. If the battery displays much higher IR numbers and/or takes longer to charge, I'd consider relegating it to test duty.

    The fun never ends! :confused:
     
  9. Charlie Cushing

    Joined:
    Jan 22, 2014
    Messages:
    56
    Likes Received:
    2
    Well, good news on one front, I've always eye balled the motors to make sure they are level, but this is the first time I've actually put a level on them, and that seems to have fixed it. Now the battery, sigh...... I'll keep an eye on it. Seriously, I've been flying RC for over 20 years and multi rotors for 4 and the MK electronics feel like I'm flying and maintaining the space shuttle some times.

    I'm still not convinced the compass issue is fixed, but in my front yard it always works fine, the issues are when I get to other locations. I've got a shoot this weekend, we'll see how the compass behaves and if it acts up, I'll be posting for GPX files.

    To all of you that have taken time to help me with this, thank you, thank you! It is greatly appreciated!

    -Charlie
     
  10. Jason Smoker

    Jason Smoker Active Member

    Joined:
    Oct 23, 2012
    Messages:
    847
    Likes Received:
    67
    Charlie if you worried about the compass and not doing waypoints. Just turn the compass effect to zero 0!!
    these will ease your worrying a little when flying
     
  11. Dave King

    Dave King Well-Known Member

    Joined:
    Dec 24, 2012
    Messages:
    2,711
    Likes Received:
    311
    Looks much better. I have not found the eye ball method for the motors accurate enough to determine if a motor is in perfect vertical alignment. I have had the same issues you did when it looked perfectly fine to me through my eyes but I found it to be a few degrees off via the bubble level.
     
  12. Charlie Cushing

    Joined:
    Jan 22, 2014
    Messages:
    56
    Likes Received:
    2
    Yes, another MK lesson learned for me, use a bubble level. I do not plan on using waypoints, but I'm using GPS position hold, if I put that compass effect to 0, will the GPS HOLD still work correctly?
     
  13. Dave King

    Dave King Well-Known Member

    Joined:
    Dec 24, 2012
    Messages:
    2,711
    Likes Received:
    311
    Yes it will.
     

Share This Page