This is a discussion to focus the feedback and support of ardupilot on the PixRacer board from

We believe that all teething problems encountered are now resolved and so we recommend people load Copter-3.3.4 which is available for all multicopters through the Mission Planner's (and other GCS's) Install Firmware screens.  Note that because regular Pixhawks are still on Copter-3.3.3 the install icon may show Copter-3.3.3 but rest assured, Copter-3.3.4 will be installed (you can check the version by looking at the very top of the Mission Planner).

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@Edgar: Micro MinimOSD should work fine, really small, cheap, fairly robust and all the features of MinimOSD. You can parallel it with telemetry if needed.

This might be your atc_accel_yaw. You might need to increase it.

I have never been able to calibrate the accelorometer in MP but have no problems calibrating it using QGC. I level it up and get started but after pressing any key after level it just stops sometimes it says ublox and some numbers and others it says left side and before I can rotate it I get an error. Good thing is I can use QGC and calibrate it and get it to arm in MP. Also , thanks Tridge, the oneshot 125 is working. Motors are now as smooth as silk now.

will try that soon, yesterday was a bit windy which resulted in bent motor shaft :) 

btw, it would be great if AC Tri firmware would support servo feedback from hall effect servos... there is a cleanflight variant called triflight which has this option, I think it would be even more helpful with EKF as now we would know the exact thrust vector of the tail, which can be used to decouple roll and yaw on tricopters. later this could be beneficial for VTOL planes. 

I know I am asking a lot here ;) 

Small update from Paul Riseborough regarding the sudden-roll-after-takeoff issue.  It seems a bug in the EKF is somewhat likely and it probably only happen if you take-off without GPS lock and then gain GPS lock soon after.

So if you want to avoid the problem, waiting until you have GPS lock before take-off is a good idea.  Note that I say, "wait for GPS lock" but to be more precise, it's actually "wait for the EKF to get a position estimate".  You can ensure this is the case by arming in a mode that require the EKF's position estimate like Loiter or PosHold.

Any chance that we could get UAVCAN to work with Zubax GNSS2. Pavel sent me a patched APMv2 for pixhawk to get me working on that platform and I would really like to try the Zubax with the racer. It is really a sweet GPS unit, would be great to have it fully functional on the APM side.
Great work on the racer, many thanks to hardware and firmware developers.

Cheers, R

As far as I know the latest UAVCAN is in master.. so I would have though that Copter-3.4-dev would work.. I guess it doesn't?

latest UAVCAN is in master. If its not working then check the following:

  • that you have set BRD_CAN_ENABLE=1
  • that you have set GPS_TYPE=9
  • that you have assigned a nodeID to the device (see manual)

Note that you can try BRD_CAN_ENABLE=2 to auto-assign a CAN nodeID, although I haven't tested that myself.

Also note that you need to reboot the board after changing BRD_CAN_ENABLE.

Nice to know it wasn't me causing the issue.  I thought maybe I was on drugs or something.

So if you fly without a GPS it should work just fine as well...

On another note it seem the Pixracer has LED's on the mother board not connected to the I2C bus.  They need to be turned on directly.  Since the code makes no distinction of that only the external LED's work.  On the PX4 stack they use an RGBled driver to control them.  Is this on the list to get working.  It would be nice to see if I have a GPS lock.....

Now that more people are using this, have other people noticed the current reading from the ACSP4 is wrong? 
Or the curve is wrong, or something?  It's correct over a range.. But then lower and higher readings are off. 
Basically, I have to have my multiplier up to about 200 to get a reading at idle (w/ all my FPV and recording gear it's consuming about 700ma at idle). 
Then w/ the suggested setting(I think it was about 36, going by memory) it's correct in the 10ish amp range.  But then it's not right over that. 

I saw one person post the other day that they didn't get a reading until pulling some amps, and suggested "it's not meant to be a low power current meter", but other power modules are...  at least, I do get a reading at idle on my other copters w/ different power modules.   If that is the official answer, I'd like to know.. then I'll stop worrying about it.

Edit--  I haven't played w/ this in a couple of weeks, and I see a lot has changed!!  So, not sure if this was addressed or not.. I'll have time to play and test it tomorrow :)

Thanks for the quick response. I have done some testing between my hex/pixhawk and the pixracer using the same GNSS2 unit. I uploaded the latest 3.4 Dev to the pixhawk and uavcan communication is good, the system works just as it did with the firmware I have been using supplied by Pavel. When I switch the GPS to the racer, enable uavcan and set parameters just as in the hawk I get the message on GCS "GPS 0 detected as PX4" repeating to infinity. No GPS signal and no compass from gnss unit.

It should register but not be very accurate at lower currents (my 3DR styles ones were anyway) -- like all these shunt based modules. I will dust off my ACSP4 and test it next week. I have been using Mauch power modules that I picked up and have not used my shunt based ones any more.

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