Comments

• Hank Deucker May 28, 2020 at 4:11pm

  I am sure most will say not again, Pixhawk telemetry. I do need help and all can be reassured that I have spent many hours scouring the net for useful information. I am not new at quadcopter flying, I started in 2012 and have progressed through many quad types and flight controllers, at present I have two 450 size quads and they fly perfectly but my big quad gives me problems. Electronically they are all identical.
  
  So to the nub of the issue:
  Equipment : Tarot 650 quad copter
  Flight controller : Pixhawk 2.4.8
  GUI : QGoroudControl version 4.0.5
  Motors : EMAX MT 3506 650kv
  Props : Various from 10X6 to 12X3.8 CF
  ESC: Racer Star 30A BLHeli
  Computer : iMac
  Tablet for missions : iPad
  
  I have very erratic take off behaviour which I have mostly solved by adjusting the Tuning Parameters in QGC. Once in the air and settled it flies as if on rails. During the flight I occasionally get confusing audio messages from my iPad re possible failure for motor number 4 generally not a problem but on a number of occasions crashes have resulted. Another message tells that the battery voltage is say 10.4V but the iPad shows 12.3V. So I hope that by accessing the telemetry logs I will find information which may solve the problem.
  
  Two types of files show up on my computer, in the Logs folder they are .bin files and in the Telemetry folder .tlog. I have looked at the files using APM Planner. Again searches for programs that can show the telemetry on screen have not helped with Mission Planner the only other program for non professionals. The information in the .tlog files is useless to me and loading the .bin files displays:
  Error preparing insertquery: ISBD table ISBD has no column named x Unable to execute statement, which is of no help.
  Can anyone list all the data elements in the telemetry file or point me to where I can read about it. Some help with what programs professionals use to analyse the data would also be very helpful as I am not totally computer illiterate.
• Hank Deucker May 28, 2020 at 1:06am

  Tomorrow, I am thinking about the wording at the moment.
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  Brian Buckmaster April 6, 2019 at 9:16pm

  I solved my telemetry and compass calibration problems. The telemetry issue was my mistake - I plugged in an identical looking module into my laptop; once I used the correct one, it worked just fine.

  The compass calibration issue was solved by replacing the GPS/compass with a new one. I guess the one I salved from a crash was somehow damaged. At any rate I now have it calibrated.

  The only issue remaining is a suitable receiver -  I was using a Spektrum satellite module from an AR8010T, but found that there is latency. I am going to order a FrSky 8XR.
  • 

    DexterIsMyHero > Brian Buckmaster February 7, 2021 at 7:34am

    Thanks for sharing this photo.
    I really enjoy seeing DIY builds, they have opened my eyes to "the possibilities".
    I am interested in the props, they seem to have anti-vortex tips.
    
    UAV prop noise can be an issue in public open areas, and there is already a lot of noise pollution where I live.
    For my first build, a Tarot 680P, I have ordered the OEM props and motors to use as a baseline.
    I am thinking about experimenting with different propellers pitch and blade lengths to address the noise issue.
    
    I understand there are guidelines for selecting motors and props, higher rpm lower torque or lower-rpm higher torque setups.
    Hopefully it will be possible to find a balance between quieter props and overall vehicle handling.
    
    I hope you and others can share your thoughts on reducing propeller noise.
• 

  Brian Buckmaster April 3, 2019 at 9:23am

  John, forgot to thank you too.  I hooked things up and tried again, but this time I got calibration failures and I decided to quit after three tries. It's a pain to do the compass dance while the quad is connected to my laptop! I wanted to power up the aircraft and use a telemetry connection to do the compass calibration, but for some reason I'm timing out - aarrgghh!  I tried plugging the telemetry module into telem port 1 and two but no joy.  Will try to figure that out later as I can pull a spare module from one of my two other quads.

  I got a screen shot of the compapss calibration page:

  

  You can see that I have compass #3 disabled and compass #1 is my external compass. Question: Do I leave the compass orientation at "none" (the default)? With the APM, I had to use something like roll 180, yaw 90 oro somoething like that as the compass is mounted underneath the GPS antenna... 

  When I begin the calibration and start moving the aircraft around the progress bar for mag 1 will become green as the calibration progresses - I see nothing on the progress bar foro mag 2 - is this normal?
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  Brian Buckmaster April 3, 2019 at 7:23am

  Golly, thanks for the help Cliff!  I did use M.P. and the compass calibration page dis not display the graphical rotating dots as I expected from doing the compass calibration with an APM. Instead, the aicraft repeated a slow beep and I started rotating the aircraft around and saw a progress bar increasing. After going through all the gyrations, I got an indicationo that the cmpass calibration was successful.

  I did not notice whether or not I unchecked compass #3 - will look at that again. I had convinced myself that this compass had gone bad as I salvaged it from a previous Tarot Ironman crash during its second test flight when the APM suffered a brownout.

  I will try again later today - thanks again for your help!
• 

  Clifton Hipsher April 3, 2019 at 5:11am

  @John Longland:

  I have never used the wizard.  I prefer using Initial Setup > Mandatory Hardware and Initial Setup > Optional Hardware.  Every thing is right there in front of you, including an all at once ESC calibration that works.
• 

  Clifton Hipsher April 3, 2019 at 5:04am

  @Brian Buckmaster:

  Power cycling is does cause you to loose settings.  Bad Compass Health means Pixhawk cannot communicate to one or more of the compasses.

  If you did not uncheck Compass #3 before you run the calibration you will get Bad Compass Health...
• John Longland April 3, 2019 at 12:10am

  Good day Brian

  I am commenting on your comment about compass calibration and "bad compas health".

  You don't describe exactly but I assume you used the wizard ( with its graphical rotating dots ) to calibrate the compass ??

  If so , I would suggest you use another method. I have bumped my head against this where I am using the wizard to calibrate everyting, ( accl...compas ... radio ..etc) and it does not seem to work. I never investigated why , but simply moved on to the following method:

  I calibrate the accel on the initial setup page of MP.

  Then I calibrate the radio on the radio calibration page of MP.

  Then I calibrate the compass with a manual method. I take my drone outside away from structures, power my drone , throttle up and right ( NOT ARMED ) . IT will beep long and then start beep..beep..beep.. then it is in calibrate phase. Then you face north, hold the drone by its tail vertically down and bring it up over your head. In the provess it will go through 270deg. Then you rotate your body a bit to the right( clock-wise ) and repeat .... until you have turned you body through 360 degrees and you are once again facing north. Then you change grip and now hold the drone by its two legs on its left side ( i.e. you rotate the drone 90 anti-clockwise ... you carry on with your waving of the drone through 270 dregree as you yourself turn through 360 ... and once the FC is happy it will double beeo and ..voila..

  I couldn;t find the youtube video in my docs but search youtuge, There is a nice video of this guy waviung his drone through 270 degrees while he is rotating !!

  looks hilarious , but it works like a bomb. Also, use the manual method to calibrate

  ESCs, not the MP wizard.

  Best
• 

  Brian Buckmaster April 2, 2019 at 4:00pm

  I need help! I have just completed a build of a Tarot 650 Ironman and I chose to use a Pixhawk PX4 for my flight controller/autopilot:

  

  I am using a MATEK 6S FCHUB PCB for power distribution, a 10S APM Power Module and 40A OPTO ESCs for my power system. The motors are T-Motor Navigator series MN3420's spinning 17" Tarot propellers.

  I am using a Spektrum satellite DSM receiver and 100mW telemetry modules. The GPS is a Ublox 7M.

  I installed the latest Mission Planner I could find - 1.3.7032.578 and installed Arducopter V3.6.7.

  I did the Accel calibration and tried the compass calibration - it seemed to be successful but M.P. told me to "reboot the autopilot"... How do I do that? Simply unplug the USB and plug it back in? I tried that but when I reconnected to M.P. I get the dreaded "Bad Compass Health" warning...

  IS there another way to reboot the Pixhawk and save my compass settings?