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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    • Dear James T Kirk,

      I had some OT replays in this thread which were simply ignored, and I learned the lesson.

      I am happily flying the 3.3 beta without any issues from RC9 up, with my setup, but some people did or do have problems, and I am pretty sure that if 3.3 was officially out and you had any issues with it, your anger would be all over the forums.

      I learned a lot about the 3.3 simply by following this lengthy thread

      So you can either be silent and wait for the official version like me, or you can contribute to the beta in any way.

      Or you can ask Scotty to beam you up to the new version, or just switch to DJI, Naza or anything else.

      The devs are doing a wonderful work so please let them decide when it's time.

      Just my 2c.

  • Randy,

    I have a unique testing situation where one of my PixHawks has a faulty Gyro2.
    It's really all over the place, completely FUBAR.
    It won't stabilize at all.

    So I was glad that in v3.3, there was an option to disable Gyros.
    Since I set "INS_USE2=0", I can now use this Pixhawk with only the single Gyro1 working.

    However, the settings doesn't always work, specially during initial boot.
    Most of the time when I plug in the battery, the second gyro is still having an impact, and I get all kinds of EKF, GYRO, errors.
    I usually need to unplug the battery a couple times in succession, before Pixhawk ignores Gyro2 values.

    My point is that the Gyro disabled function, should be before any Pre-Arm checks.
    I haven't looked at the code, so I am not sure how it is now.
    But Pre-arm, Nav checks, definitely still check gyro2 even though its disabled.

    I also have my settings to skip INS Pre-Arm checks for this Pixhawk.
    Allowing it to eventually arm and use GPS modes.

    if you plan on making any code changes to how the INS_USE variables are used, I can test for you if its working, with my crippled Pixhawk.

    Also I can confirm that EKF errors do recover better, as per the release notes.

  • 3.3 c12 seems to have better alt hold than 3.2. Mine use to ascend going CCW and descend CW or vice versa I forget. But doesn't seem to do it at all now. 

    • @Richard

      I haven't forgot the file; worked all weekend, will get them tomorrow time permitting. Sorry.

      • Thank you. I messed with it for a couple hours... still not having much luck.

    • I agree, were I have Pix with int compass, APM compass with 3.2.1 didn't works. I need more calibration but difference is noticeable.:)

  • Managed to get some testing with both a Hexa and a Quad, both with a clean install of RC12, i.e. running default values. Did calibration of radio and compass at the field on both uneventfully. Did not have opportunity to run auto-tune or even manual tuning.

    Both copters flew admirably well, and a friend that was with me at the flying field and uses PixHawk on planes was overwhelmed by how good both copters flew.

    @Randy . IMHO 3.3 is ready to rock'n'roll. Press the button :)

    Bad note to this is downloading logs using MissionPlanner, that keeps throwing out errors but thank god for MavProxy or even APMPlanner



  • Since people have been talking about compass issues, I'll mention an observation..
    My copter seems to get dizzy when I rotate/yaw. 
    I can be hovering completely stationary, EKF is all very low, green.  Then I yaw around in a circle, EKF compass goes into the red, and the copter no longer holds a steady position. It circles around a point. 
    But, I can yaw again, back in the opposite direction, even just 20 degrees or so, and the EKF mag reading goes back down into the green, and the copter behaves better.    It's somewhat random as far is how much I have to yaw before the issue appears, but yawing around sometimes puts the ekf compass into the red, and yawing back fixes it.

    I didn't notice this issue in previous versions of copter, or even early 3.3 betas..  But then again, the EKF meter wasn't there making it obvious.

    • The EKF is very good at dealing with compass intereference/offset issues but that does not mean they are not there. You almost certainly have issues with the compass calibration or with interference. I have found that the live EKF viewer is a fantastic way to determine which. Simply connect your copter to USB power and wave it around. The EKF mag should never go above 0.5 (green). If it does then you should recalibrate. If it does not but it does in flight then you have interference (or vibration) issues - you should run compassmot or move the compass (and check vibration). There is also a small but non-negligable possibility that you have bad gyros, so worth checking those if the others do not give you the results you want.

      [Weirdly I can get an EKF spike if I point the nose sharply straight up, but no-where else (not even upside-down). I suspect this is an artifact of the vertical mag field where I live, but would be interested to know a more informed scientific opinion on this!]

      • Good simple test to do, I'm going to try too, flags help a lot to do it easier, thank's for the tip Andy

        (my graph is outside on the open field)

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