My Flying Wing UAV platform

[lukasz]

Tom,
I have noticed a problem when exporting KML Track file from my last flights.

When selecting in Google Earth "Show Elevation Profile" I don't know why but when I move over the diagram it's pointing me somewhere to Atlantic Ocean.

Did you see something similar?
It's pointing me to Latitude 0 and longitude 0 - those are the values entered for CIRCLE_REL

I have attached the file for you.

04.09.2010_6.1.kml

(159.89 KiB) Downloaded 1315 times

[Tom]

Hi Lukasz,

Yes this appears to be a bug. If you open the .kml file you'll see that the last 5 or so positions are "0.0, 0.0". When you delete those everything works fine. I'll fix this in the next version!

How is the circling going? Maybe you need the make the P a bit larger in Roll2Aileron or Heading2Roll?

[lukasz]

Circle is going quite good
Only thing I noticed is that the plane doesn't hold the altitude, but this might be a calibration issue or still I need to work on trimming the plane.

On manual flight it looks that it's properly trimmed but need to work on this.

Regarding "P", at the moment I have all "P" values set to 0.7. For one or two flights I had those values set to 1 but then the plane was oscillating around roll axis.

Also I will need to take a closer look at those values. Might try to leave P roll as 0.7 and work with remaining two.

[Tom]

If you send me the XML datalog I can take a closer look...

[lukasz]

here you go:

04.09.2010_6.rar

(62.11 KiB) Downloaded 1339 times

and here is the classic KML file for same flight:

04.09.2010_classic.kml

(127.47 KiB) Downloaded 1298 times

[lukasz]

Tom, did you have the chance to look at attached xml?

[Tom]

Hmm yes. It seems as if your pitch angle was negative, while you were still climbing. I can only conclude that probably your calibration was not perfect. Did you calibrate using the FTDI cable's 5V connected? Was your module perfectly flat when calibrating?

[lukasz]

thanks for looking into this.

I did the calibration on a flat table - it's perfectly horizontal and the module was lying horizontal.
I did the calibration using FTDI cable without ESC powered.

The case might be that the module is not mount parallel to wing chord.

[Tom]

Even though the pitch sensors work on 3V3, I did found a better accuracy when you do the calibration with the ESC connected as power source (unplug the red wire from the FTDI cable to make sure you don't have 2 power sources)

Check whether the module is along the wing cord.

On the next flight you can try to calibrate the gyro sensors before take off (when the module is still on the ground: yaw to the left and roll to the right with your RC-transmitter). This will set a new neutral value for the gyroscopes (this can differ due to large temperature differences or long time). In the future I'll try to make these gyroscopes auto-calibrate.

[lukasz]

Thanks Tom for your guidelines.

I will try to calibrate the sensors using ESC power. I remember that I tried to connect FTDI cable without power (red cable) having the board powered through ESC and I didn't see any readings in GluonConfig tool. I will check this out once again today.