Copter-3.3 beta testing

Warning #1: an issue has been found with Tower's Pause button which can cause the vehicle to fly to an old position if the vehicle has not sent a position update to Tower in some time.

Warning #2: Copter-3.3.2 fixes a bug found in Copter-3.3.1's desired climb rate initialisation which could lead to a sudden momentary drop when switching from Stabilize or Acro to AltHold, Loiter or PosHold.

Warning #3: Copter-3.3.2 fixes an issue found in Copter-3.3.1 which could lead to hard landings in RTL or AUTO if the WPNAV_SPEED_DN was set too high (i.e. >400 or 4m/s) and/or the WPNAV_ACCEL_Z was set too low (i.e. <100 or 1m/s/s).

Warning #4: a bug was found in Copter-3.3 which could cause a sudden crash if you abort a Take-off initiated from a ground station.  Video description is here.  The bug is fixed in Copter-3.3.1 so we recommend upgrading.

Note #1: AC3.3-rc8 corrected a long standing bug in the HDOP reporting.  HDOP values will appear about 40% lower than previously but this does not actually mean the GPS position is better than before.
Note #2: if upgrading from AC3.2.1 the vehicle's accelerometer calibration needs to be done again.
Note #3: set SERIAL2_PROTOCOL to "3" and reboot the board to enable FrSky telemetry like in previous versions.
Note #4: the wiki will be updated over the next few weeks to explain how to use the new features

Copter-3.3.1 is available through the mission planner.  The full list of changes vs AC3.2.1 can be see in the ReleaseNotes and below are the most recent changes since AC3.3.

Sadly this version (and all future versions) will not run on the APM2.x boards due to CPU speed, flash and RAM restrictions.

Changes from 3.3:

1) Bug fix to prevent potential crash if Follow-Me is used after an aborted takeoff

2) compiler upgraded to 4.9.3 (runs slightly faster than 4.7.2 which was used previously)

Changes from 3.3-rc11:

1) EKF recovers from pre-arm "Compass variance" failure if compasses are consistent

Changes from 3.3-rc10:

1) PreArm "Need 3D Fix" message replaced with detailed reason from EKF

Changes from 3.3-rc9
1) EKF improvements:
    a) simpler optical flow takeoff check
2) Bug Fixes/Minor enhancements:
    a) fix INS3_USE parameter eeprom location
    b) fix SToRM32 serial protocol driver to work with recent versions
    c) increase motor pwm->thrust conversion (aka MOT_THST_EXPO) to 0.65 (was 0.50)
    d) Firmware version sent to GCS in AUTOPILOT_VERSION message
3) Safety:
    a) pre-arm check of compass variance if arming in Loiter, PosHold, Guided
    b) always check GPS before arming in Loiter (previously could be disabled if ARMING_CHECK=0)
    c) sanity check locations received from GCS for follow-me, do-set-home, do-set-ROI
    d) fix optical flow failsafe (was not always triggering LAND when optical flow failed)
    e) failsafe RTL vs LAND decision based on hardcoded 5m from home check (previously used WPNAV_RADIUS parameter)

Thanks for your testing!

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  • Not sure if this has been reported before, but setting either CONFIG_SONAR, CAMERA or AC_RALLY to DISABLED prevents Copter from building.  In the case of AC_RALLY that seems to be a simple typo, in case of CAMERA misplaced #ifdefs, but in the case of CONFIG_SONAR it seems like building without it is no longer supported?  I needed to touch up too many places to build without sonar.

  • I had a little incident today flying rc10. First off, The copter was in the trunk of my car all day and was a little warm when when it was initialized. The problem is I had had a radio fail-safe and it hit full throttle for ~ 1/2 sec and then dropped and revved up again. It hit 60 A witch is the max. Going from loiter to RTL, and once from RTL to loiter the throttle revved and then the copter jumped up then it sank back down(corrected the overshoot). I thought I just imagined it, I was flying fpv the first RTL. I watched the onboard video and confirmed that. I haven't changed any params, it must be something to do with a temp change after start up.

    2015-09-16 19-04-25.bin

    • Developer


      As discussed on mumble, after looking at the logs it looks like a baro disturbance to me.  We've recorded a few situations where the EKF doesn't deal well with barometer disturbances and the altitude estimate and climb rate estimate become inconsistent.  In this case as well we see the impossible situation where the climb rate is negative even though the altitude is climbing.

      Leonard, Tridge and I have discussed with Paul (ekf expert) and we hope the "new maths" coming in AC3.4 will deal with this situation better.  Until then the only solution is to try to reduce the barometer disturbances like tohse that happen when the vehicle suddenly slows after fast forward flight (this is what happens when RTL is engaged)

  • well i like to report my copter is performing very well since AC3.3rc10 and recently rc11.

    I believe good status should be reported as much as bad one and problems alone....and I have been lucky to not have any issues so far in over 30 flights, no complains (well except for MP not being consistent and GCSs not being able to read darn AC3.3 log files!!!)

    But anyways, just my 2 cents, based on my experiences with it I would say is ready for prime time...but thats just my take on it...hope others are having good experiences too, not just bad

    Randy and Leonard have been great when I needed any help, and in more than one occasion I was ready to blame the beta software for issues that turned out to be hardware related with the copter....

    • Hello, I would like to report a very good performance as well! Good job!

      By now I have flown more than 10 batteries without any issue. The only one that I have found was different autotune results, all of them are overshooting a little. Could be my setup, but I don't think so. Let´s wait for more autotune tests to see if there is something weird with it.

  • rc11. I'm struggling to see what's going on. The quad (250) flies quite well although is not tuned (see other posts). The compass innovations (SMX,SMY,SMZ) are too high and yet the compass calibration seems quite good with both compasses tracking each other. Vibrations appear low. No gyro drift. GPS velocity errors are low-ish (SV). Baro errors (SH) low. Any clues? Logg attached as its to hard to show a composite graphic with all of these.


    • I'm getting the dreaded "Inconsistent compasses" from time to time as well.

      • for that I have very non-scientific method to deal with - when you do compass calibration note the form of 2 spheres it renders on the screen. if either compass' image shows more like a compressed/distorted football rather than an ideal basketball :) - it means you will never get rid of compass variance errors.

        I have one 45mm gps unit from witespy that does that, so, somehow its compass sensor got screwed up.

        An another same exact unit works fine and gives no errors. that is considering the compass in the auav unit is rendering perfectly fine with no errors - that has to be checked first, with a disconnected external compass.

        if with a disconnected gps compass and properly calibrated internal auav compass you still get compass variance error - having confirmed during calibration your sphere of values looked well formed -

        and with auav out of the drone body on a ground plate is also gives same error - its compass should be replaced.

        you can also try to alter EKF_ option to 1 to reduce sensitivity of that check, I do not remember now which one but it exists.

    • Andy, any chance you are using a pixhawk lite?

      • AUAV-X2

This reply was deleted.


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