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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              • It is strange, that buzzer generates signals after ARMing.

                My Mariner copter is closed body design, and never hear the buzzer.

                I do not think that anybody will listen it in the flight! For security reason is better to disable the signals after takeoff. 

        • Developer

          Right of course!  Sorry, we've seen this before, it just slipped my mind.  Thanks for that Greg!

      • @Randy

         Is there a way we could check pixhawks not yet integrated in a system for this fault?

           It would help a lot


        • Developer


          The divergence should be visible through the mission planner's Status tab (go to Flight Data screen and look on the bottom left) and then compare az vs az2.  The difficulty is that the problem is intermittent.  So for much of the flight above the numbers are very close.  In fact, we have a pre-arm check that will warn, "inconsistent accels" if there's a problem before takeoff.

      • Randy,

        Every day in every extent I am learning something more.

        Thank you for the graph and the explanation of the problem source.

        I must confess I noticed it but didn't know how to interpret the sudden separation.

        This one goes into my knowledge book.

    • I am no log expert, but here are my 2C

      Your vibration levels seem reasonable for me, so I don't think it's a vibration issue.

      But when I checked you CTUN.ThrOut it has a mean value arround 510, and your THR_MID is set to 700.

      So when you switch to one of the altitude mode your throttle jumps to 700 and your IRIS+ fly's to the skies.

      Try setting your THR_MID to 510 and see if that helps.

      • I have exactly the same problem with new firmware 3.3.2, after switch from stabilize to alt hold, flying up at full throttle. Here is the link to my publication.

        I have tested on two different Pixhawk installations, both had very good alt hold and auto before the upgrade...

  • I am needing some advice. I had to do a hard restart of my laptop and when downloading Mission Planner,i ran into a problem that needs some clarification. When downloading,the driver download failed on laser navigation,but would still let me finish download. I am not using laser at the present,SO,will this affect MP, or my normal firmware,or the way the copter will fly?? A little advice would be appreciated. Also, if there is a way for me to get those drivers to pass would be great as well. Windows 8.1 with signature cert disabled. Thank you in advance. Frank.

    • Sorry, but for some reason after disabling driver sign cert again,they loaded fine. Thank you anyway. Frank.

  • Randy

    Do you know if the FrSky Taranis Telemetry will be supported in 3.4 so there will be no need for a teesny board just a direct connection to the smart port on the X8R rx?  I know there were people working on that. I think that would be a huge upgrade to the copter FW as it has become a very popular radio and adds a tremendous amount of info to the pilot without the use of a separate GCS. I would even go so far as to say it adds a great deal of safety  being as one can see the battery level and or get a warning when it gets low.. let alone all the other data it provides. 

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