First CS8 Build - Problems with PH

Discussion in 'Cinestar 8' started by Bryan Monarch, Sep 18, 2014.

  1. Bryan Monarch

    Bryan Monarch New Member

    Joined:
    Jul 21, 2013
    Messages:
    15
    Likes Received:
    2
    Hey everyone,

    Not going to lie, I'm actually really psyched I finally have a reason to post here. I've been watching this forum for over a year trying to learn and figure out what I needed when I decided to go with my first CS build. I've flown Multirotors for about 2 years now, and this is my first venture into the HL category (even though right now I'm only flying a 5DMarkIII on the M5). Here she is:

    [​IMG]

    Anyways, I'm having some trouble with the GPS. Normal flight under No GPS has been wonderful and Altitude hold is working great as well. However, whenever I flip into PH, my craft will stay steady momentarily, and then start to bank pretty quickly left. I've tried re calibrating the GPS several times, each time pointing as close to magnetic north as I can, but still have the same outcome.

    Anyone have any ideas of things I could test?
     
  2. Steve Maller

    Steve Maller UAV Grief Counselor

    Joined:
    Oct 30, 2012
    Messages:
    3,979
    Likes Received:
    807
    Congrats, Bryan. It's a great feeling to get one of these wonderful birds in the air.

    As far as your GPS problems go, are you familiar with pulling GPX files? Do you have a microSD card in the Nav board? The GPX files may help diagnose the problem. One thing I see is a Very Large LiPo that clearly blocks the GPS's view of the sky, and LiPo power leads right next to the GPS, too. I'd rotate your battery tray 90°, and maybe see if you can put some spacers to raise the nav/gps a bit higher. I'd be curious to see if you're losing GPS reception as the copter yaws or the current jumps.
     
  3. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
    Staff Member

    Joined:
    Jul 31, 2012
    Messages:
    10,364
    Likes Received:
    1,162
    My congrats too Bryan.

    You puzzled me with one statement, though: "I've tried re calibrating the GPS several times, each time pointing as close to magnetic north as I can, but still have the same outcome."

    What exactly did you mean by "re-calibrating the GPS?" Are you talking about recalibrating the magnetic compass? (Tipping the copter end-over-end?) or something else?

    Andy.
     
  4. Bryan Monarch

    Bryan Monarch New Member

    Joined:
    Jul 21, 2013
    Messages:
    15
    Likes Received:
    2
    Hey Andy,

    Apologies, I'm still stuck in Naza speech. Yes, that's what I meant, recalibrating the magnetic compass, the rotating of the copter over it's head.

    Steve,

    I will pull the GPX files sometime tomorrow. I've never actually done it before but I'm pretty sure I should be able to figure it out. The GPS is mounted out on boom 1 and the battery (a 10,000 mah QC) is mounted above the FC, essentially perpendicular to the GPS hood. I've been realizing a lot of you go with the two battery setup with batteries mounted perpendicular to booms 3 and 7 on either side of the FC, and eventually plan on going that direction but for right now am just doing a 1 battery setup for the ease of the setup. That particular picture doesn't show it very clearly (this was before my first flight) but when a battery is plugged in, it's actually on the other side of the battery, so at least 8 inches away from where the GPS is mounted.
     
  5. Gary McCready

    Gary McCready Active Member

    Joined:
    Oct 26, 2012
    Messages:
    284
    Likes Received:
    42
    Bryan: Looks good, congrats. I had problems with compass headings intermittently: Users have suggested shrink wrap on battery leads, which I did, but I got the best results when I switched to the external compass. (can't tell if you have one?)
     
  6. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
    Staff Member

    Joined:
    Jul 31, 2012
    Messages:
    10,364
    Likes Received:
    1,162
    Bryan: My working hypothesis is that you did not get a GPS 3D Lock before you flew the copter --- but that's pure speculation on my part, so you really need to check the evidence....

    Can you confirm, by hooking up MK Tool to the Flight Control or Navigation Control Board and then selecting the GPS, that you are indeed getting a GPS lock? (Or can you confirm that you saw the small blue LED on top of the GPS antenna flashing -- it's solid when searching for a lock, and flashing when you obtain a lock).

    You can also tell whether you got a GPS lock by looking at the GPX file of some of the flights in question. Do a Google search for MK_GPXTOOL and download that and you can examine the GPX file more easily....or use a text editor if you're feeling masochistic -- GPX files are plain text files but are encoded in XML (eXtended Markup Language) and not really fit for human consumption.

    Andy.
     
  7. Jason Smoker

    Jason Smoker Active Member

    Joined:
    Oct 23, 2012
    Messages:
    845
    Likes Received:
    67
    I'm gonna put my 2 cents in. If you not using waypoints I would turn your compass effect to zero.
    It can cause problems. Don't ask me how I know ;(
     
  8. Bryan Monarch

    Bryan Monarch New Member

    Joined:
    Jul 21, 2013
    Messages:
    15
    Likes Received:
    2
    Hey guys,

    Sorry for taking so long to get back. I ended up getting the GPX data pulled from a couple of the flights, and from what I can see, I don't see any problem with the GPS lock. At the bottom, it says I have no errors. Also, Andy, in all of the flights, I waited until I had the flashing blue lights. Here is an example of one of the flights:

    Flight date: 9/8/2014 2:10:04 PM
    Flight time: 2:10:04 PM.2 - 2:13:16 PM.6
    Duration : 192 secs, 00:03:12
    Batt. time : 191 secs, 00:03:11

    Start Location : +46.2201803 / -119.1485992 @97.1m
    Elevation(GPS) : 0.168 6.76 10.21 m (min/avg/max)
    GPS alt. (raw) : 97.092 102 107.134 m
    Altitude(Barom.): -0.6 5.65 9.2 m
    Vertical speed : -0.81 0.03 1.27 m/s
    Max speed : 10.3 km/h
    Max target dist.: 0 m
    Max distance/LOS: 25.7 m / 27.2 m

    Sats : 8 8 10
    Voltage : min. 22.8, max. 24.4 V
    Current : 0.5 50 64.6 A
    Wattage : 12 1191 1472.88 W
    Capacity: 2685 mAh

    Motor1: 0.0 5.8 7.3 A Temp: 38 40 43 °C
    Motor2: 0.0 6.3 9.4 A Temp: 34 39 43 °C
    Motor3: 0.0 6.1 7.9 A Temp: 36 37 41 °C
    Motor4: 0.0 6.4 8.5 A Temp: 37 44 49 °C
    Motor5: 0.0 5.5 7.5 A Temp: 41 44 48 °C
    Motor6: 0.0 6.2 7.8 A Temp: 40 47 51 °C
    Motor7: 0.0 4.7 6.8 A Temp: 42 46 49 °C
    Motor8: 0.0 7.1 9.4 A Temp: 35 41 45 °C

    Magnet Field: 95 97 101 % (ok)
    Magnet Inclination: 60 69 78 deg

    No errors found ;)

    I'm not sure what to try next. I've ordered an external compass just as a possibility. Anyone have any other ideas of things I could test to try and find the cause?
     
  9. Jason Smoker

    Jason Smoker Active Member

    Joined:
    Oct 23, 2012
    Messages:
    845
    Likes Received:
    67
    hey Bryan you might want to upload a the whole gpx file it gives us a better understanding whats going on. If possible the one when banks left.

    that gpx files looks fine. by my standard! :)
     
  10. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
    Staff Member

    Joined:
    Jul 31, 2012
    Messages:
    10,364
    Likes Received:
    1,162
    Hi Bryan: Yeah, as Jason suggests, upload the entire GPX file -- and tell us when in the flight you think the copter is banking left.

    Can you confirm that you have done an ACC calibration, please -- that's with the Flight Controller absolutely level (you'll need a spirit level) and then move the left stick on the transmitter to the top right hand corner until you hear some beeps.

    You should only need to do this calibration once -- it's not the same as the gyro calibration that you have to do before each flight.

    Thanks
    Andy.
     
  11. Bryan Monarch

    Bryan Monarch New Member

    Joined:
    Jul 21, 2013
    Messages:
    15
    Likes Received:
    2
    So I re-did my ACC calibration just to make sure everything was good there. I leveled it perfectly and brought the stick to the top right.

    This morning, I went out and flew a couple of test flights to make sure I could try and pinpoint when the attempts to go into position hold were. Same result this morning, sharp movements mostly towards the West.

    I've uploaded the GPX file to my Google Drive so you all can take a look at it. I tried Position Hold at least twice during this flight, both near the end of the flight (just before I landed and double checked battery life).

    https://drive.google.com/file/d/0Bxe-0PIn1LA6LTRwSC1UNC1tLVE/view?usp=sharing

    There is the file. Hoping you guys find something I'm not seeing!

    Bryan
     
  12. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
    Staff Member

    Joined:
    Jul 31, 2012
    Messages:
    10,364
    Likes Received:
    1,162
    I've looked at the GPX file (by the way, Google Drive is not the way to go -- just use the Upload file button -- too many steps to get Google Drive to disgorge the file).

    Here's the curious thing -- it looks like the aircraft takes off and flies more or less backwards -- that is boom #1 is not facing the direction of flight -- using MK_GPXTOOL I looked at the flight superimposed on Google Earth satellite images and you can see the flight path (thin magenta line) stretching up and to the right of the copter -- but look at boom #1 -- the red boom on the icon -- it's completely out of alignment with the direction of travel.

    Bryan Monarch 2014-10-03 at 16.08.41.png

    Can you confirm that you have the flight control board correctly oriented to boom #1. Also confirm that you have the GPX antenna correctly oriented to boom #1, please.

    Thanks
    Andy
     
  13. Gary Haynes

    Gary Haynes Administrator
    Staff Member

    Joined:
    Jul 6, 2012
    Messages:
    5,211
    Likes Received:
    460
    Bryan also post a close up photo of the stack on the front boom with the GPS puck. Also what boom number is the GPS on? From you photo it looks like it is on Boom 5.
     
  14. Bryan Monarch

    Bryan Monarch New Member

    Joined:
    Jul 21, 2013
    Messages:
    15
    Likes Received:
    2
    I've confirmed that all the necessary parts are pointing in the direction of boom #1. The ESC, FC, and GPS puck are all pointed towards Boom #1. The GPS puck is mounted on Boom #1 as well.

    Since I don't really know how to work the GPX stuff all that well (I'll watch the video I got from QC about it tonight.) I'm not really sure how to see what you're seeing, Andy, but that does seem odd that flight was constantly seen as backwards. I flew in a forward direction for this flight with Boom #5 pointing my direction pretty much the entire time.

    Here are some images.

    IMG_0025.JPG IMG_0021.JPG IMG_0026.JPG

    The main thing I'm wondering now is if maybe my soldering job on the GPS hood was poor (I'm pretty new to this whole soldering business.)

    Also, I've uploaded the GPX file here as you suggested, Andy, so it's easier for people to take a look at. Thanks for the heads up.
     

    Attached Files:

  15. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
    Staff Member

    Joined:
    Jul 31, 2012
    Messages:
    10,364
    Likes Received:
    1,162
    Hmm. OK, that eliminates that.
    Next question: Can you hook up with MK Tool via the MK USB adapter and then connect to the Flight Control Board.
    Save the settings to an .mkp file and post that....along with screen shots of the MISC window and the EASY SETUP window, please.

    Thanks
    Andy
     
  16. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
    Staff Member

    Joined:
    Jul 31, 2012
    Messages:
    10,364
    Likes Received:
    1,162

    1. Don't trust that MK Tool video from QC. That idiot doesn't know what he's talking about -- if it's the video I'm thinking about... :)

    2. The GPS shield would not affect the orientation.

    I'll have another look at the GPX file.

    Andy.
     
  17. Bryan Monarch

    Bryan Monarch New Member

    Joined:
    Jul 21, 2013
    Messages:
    15
    Likes Received:
    2
    Haha, I just connected your name to the video. Not an idiot in the slightest. I wouldn't have been able to do any of this without your help.

    I've attached the settings I'm running and also included the screenshots below.

    Easy Setup.png MISC.png
     

    Attached Files:

  18. Gary Haynes

    Gary Haynes Administrator
    Staff Member

    Joined:
    Jul 6, 2012
    Messages:
    5,211
    Likes Received:
    460
    Bryan

    I notice that you are in Mode 5 rather than the more typical Mode 3 (number down at the bottom of the setup screen). This may be part of the issue unless you specifically picked mode 5.

    Also your landing gear setup is not standard. Looks like it is off 180 degrees. Consider changing the alignment if you plan to hang a camera under the center deck pointing forward.
     
  19. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
    Staff Member

    Joined:
    Jul 31, 2012
    Messages:
    10,364
    Likes Received:
    1,162
    Mode 5 might well be the problem, Gary.

    It certainly will not help. Bryan, on the Video these are referred to as Parameter Sets or Configurations. Think of them as five different configurations for MK Tool Parameters. Unfortunately it's all to easy to change these Parameters Sets just using the control sticks on the Transmitter. Read more about this here: http://wiki.mikrokopter.de/en/MK-Parameter/Easy-SETUP (including how to accidentally set the parameter set using the sticks.

    Each configuration is independent so you have to select it, change it and then write it back to the Flight Control Board -- so if you make changes to configuration 5, write it to the FC board and then select configuration 3 you will not have changed configuration 3!! By the same line of reasoning, if you wanted to make the same particular change to all the configurations, you'd have select each configuration, make the change, and write it back to the FC. In practice we typically just stick with configuration 3 -- but it's the first thing to check if you get weird flight characteristics.

    If it doubt, force the FC to Configuration 3 by using these stick settings -- it's worth printing out this as reference card. You wouldn't be the first person to think they were calibrating the gyros but in fact calibrating the ACC, or accidentally changing the configuration.

    The "Settings" shown below are the Parameter Sets/Configurations.

    BUT NOTE: The modern "motor stop/start" is not shown correctly below -- it's showing the old single stick method:

    Mikrokopter Stick Setting Positions.png

    Here are the new Motor stop/start settings -- you can also move both stick to the lower right too (if you enter OFF in the motor safety switch setting in MK Tool, then it reverts to the "old" settings above):

    Mikrokopter New Motor Stop Start.jpg

    You might also want to UNcheck the "ignore magnetic error on startup." You want to know if you have a compass error! (It's down the bottom of the MISC screen.)

    Nothing else appears out of whack....

    But there is definitely a problem with the orientation of the copter as I mentioned. I still need to have a look at the GPX file again.

    Andy.
     
  20. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
    Staff Member

    Joined:
    Jul 31, 2012
    Messages:
    10,364
    Likes Received:
    1,162
    Hmm. On http://wiki.mikrokopter.de/en/MK-Parameter/Easy-SETUP

    It shows (under Name of Configuration) what might be that configurations 3, 4 and 5 are all set to Easy. It's written rather strangely, just repeating Setting 3 three times, but I think that's what it means.

    In which case, configuration 5 should be the same as configuration 3.

    Andy.
     

Share This Page