[sam028]

Can you post your config file ?
File > Export UAV Settings

Sure, here it is.

I did 3 flights today, after the last thermal calibration:
- same crazy gyros behavior with the first battery pack, then calibrate the gyros bias and the accelerometer: no changes
- calibrate (with OPLink) the gyros bias and the accelerometer: was much better with very stable flight and good position hold
- all good with the next two battery packs (10 minutes flights each time)
So that's a bit weird...

Thanks.

[f5soh]

Gyro biases are really weird in your config file.

Try loading the file attached (for default Gyro values, without temp calibration) and switch to Complementary.
Reboot board, just to be sure.
See what happens and made a log file to be posted here : Tools > Start Logging and after a few minutes Tools > Stop Logging

[sam028]

Gyro biases are really weird in your config file.

Try loading the file attached (for default Gyro values, without temp calibration) and switch to Complementary.
Reboot board, just to be sure.
See what happens and made a log file to be posted here : Tools > Start Logging and after a few minutes Tools > Stop Logging

Here you go.

Thanks.

[f5soh]

Looks good, you did a short flight, right ?
No big biases, gyro readings around zero and no drift.

I think the previous temperature calibration was messed for some reason.

[sam028]

Yes, it was a 2 or 3 minutes flight.
I'll keep this config and will get back to INS13 to see how it goes.

I was going to ask how to read logs but I finally found it! I'll add an how-to article about it, as it's obvious and logical to manage it with through the Connections combo box it's not extremely intuitive (as the "Start logging" is the menus I was searching for a sort of "Read logs" there too).

[f5soh]

If you want to write something about logs, the best place is Wiki. Maybe a page around the Import/Export settings.

[jdl]

Yes, it was a 2 or 3 minutes flight.
I'll keep this config and will get back to INS13 to see how it goes.

Just looked at the opl log. Maybe it's a good idea to sort the baro problem first and then try again autonomous modes. Logged altitude readings don't seem right to me...

Temperature readings of both sensors (Gyro and Baro) show values (28..21 deg.C) that are outside of the calibration range you cited above. You may wish to redo the thermal calibration with higher end temperature. I use the freezer and then the kitchen oven switched to minimum (it has no fan!), board placed on wooden plate. This gives a nice range of -13 .. 80 deg.C or similar.

Also, there is something weird with baro height readings. Recorded values start at height -116m, jump to -128m after takeoff (prop wash?! maybe the foam over the sensor I saw on your photos is not covering firmly the barosensor).

During flight height reading reaches -102m. You land at -106m (huge difference with the takeoff height) and till the end of log file the height creeps slowly to -112m.

I recall there was a thread, started by the TheOtherCliff, about "bad" Revo boards with problematic voltage regulators, that affect baro sensors.

https://forum.librepilot.org/index.php?topic=311.0

[f5soh]

Baro issue related to regulators give noise with instant spikes, sometimes a few meters. That's not the case here.

Drift is related to temperature change, baro and Acc give almost the same temperature.



The thermal calibration is dedicated to correct this behavior.
Of course this behavior can be reduced physically by simply using a case around the board.

[sam028]

Not sure for the baro (I'll remove this C9 capacitor sooner or later) but something looks wrong with my board.
With INS13 it was impossible to arm the copter, ATTI and STAB were red and the gyros data not correct (see my short log file, with the board not moving). Things were fine when I get back to Complementary mode.
I just ordered another Revo board (from HK this time) so hopefully I'll be able to compare both boards.

[f5soh]

Removing the capacitor will not change something for you, altitude still within less than one meter.
Bad regulator can give 5m spikes, look scopes and scale to the left in Wiki page.

Here is what you recorded with latest log:


You may try to do a thermal calibration again. No light, no vibrations or bumps while calibrating.
You can put the board inside a piece of tissue so it warm a little more.

With INS13 it was impossible to arm the copter, ATTI and STAB were red and the gyros data not correct (see my short log file, with the board not moving). Things were fine when I get back to Complementary mode.

Previous Gyro biases comes from bad thermal calibration, my Revo give the same jitter and erratic STAB initialization here with your settings.
When you arm the board, frame will be perfectly steady.

[sam028]

New revo board received and plugged in. I did a quick flight in Complementary mode and so far so good. The baro on the previous board was good but this one looks better.

But now I'm stuck with the OPLink configuration, no communication... Here my setup:
- copter side: https://www.screencast.com/t/1toFEzfBQ
- ground station side: https://www.screencast.com/t/QJ9m3qT0LK
And yes, the antennas are plugged on each side.

Any idea of what could be wrong?

[TheOtherCliff]

Any time you make changes to RF settings, you must have that board directly plugged into USB.  This means that you should use USB to change Reve RF (OpLink) settings.  Start from there.

GCS set to OpLinkCoordinator
Revo set to OpLinkReceiver

Leave DeviceID set to AutoGen on both sides.

Copy DeviceID from coordinator side and put it into CoordinatorID field on Revo side.

I suggest you use 57600 for CommSpeed (both sides).

Both set to "data only" and all other settings matching.  For this initial testing, set power low on both, like 1.25mw

[sam028]

Thanks @TheOtherCliff, I already did all this but no joy (I also try after an Upgrade & Erase firmware).

I think the OPLinkMini board has a problem (while it worked well for more than a month) and here is something I don't understand:
- screenshot from the OPLink coordinator (plugged in USB on machine A): no RX and good TX, link state "Enabled".
- screenshot from the Revo board (plugged in USB on machine B): some RX but no TX, RX level not null, link state "Connected".

It looks like the OPLinkMini can't receive anything but on the other hand RadioComBridgeStats has TelemetryTxBytes and TelemetryRxBytes > 0. 

Any clues/ideas?

[TheOtherCliff]

Lately the cheap clones from China are sometimes off frequency.  I haven't got any bad ones.  The latest LP unreleased code has a tuner slider in the OpLink settings.

You start with a set of OpLinks that work well together and adjust your new bad ones to work well with the working set.  Adjust for best received signal levels.

[sam028]

Lately the cheap clones from China are sometimes off frequency.  I haven't got any bad ones.  The latest LP unreleased code has a tuner slider in the OpLink settings.

You start with a set of OpLinks that work well together and adjust your new bad ones to work well with the working set.  Adjust for best received signal levels.

I have now 3 Revo boards but only 1 OPLink mini, so I'll get some to continue the investigations.

Is there a way to use a Revo board as an OPLink coordinator in LP? I bound 2 Revos, one on the ground side acting as coordinator but LP see it as a "normal" board, it's not acting as a simple OPLink.

Thanks.