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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  • Is it possible that the Terminal (CLI) is not working since AC3.3?

    I would like to try AC3.3 but since rc5 (the first -rc I tryed) I got this:


    • Developer


      It's disabled because you should be able to do everything you need (log downloads, compassmot, etc) using new MP features that use MAVLink instead.  If you really want to use the CLI there's a new parameter called CLI_ENABLE that can be set to "1".  The CLI itself has been cut down massively though so many featuers are gone from it.  We did this because it eats up developer and testing time to maintain multiple methods of doing the same thing.

      • T3


        is there any other tool available where one can easily select what should be logged? This was prefect with the CLI.

        • Welcome to the Linux mentality of software development. This is where the end user's experience is the bottom of the list of things to accomplish. It's just the nature of FOSS where things get done not because it's the right thing to do or will better the experience but because it is the pet project of the dev(s). We "like" to think all this stuff is for us, but it is not, it's for the devs. That said I am so glad that there are still devs willing to take their personal time to do any of this at all.

          • Developer

            Hi Craig,

            I am sure I can speak on behalf of all the devs when I say thank you for your kind words of appreciation. 

        • Developer


          The latest mission planner shows individual check boxes for bitmask fields so it's much more convenient than before.


          • well, actually this seems easier than the CLI. Maybe I should give it a try someday:)
          • T3


            thanks! Perfect! I overlooked this because I am normally working with the full parameter list only.

        • I never tried but you should be able to download your logs through MP as Randy mentioned.

          I understand where you are coming from though. I am also so used to using CLI, I like to keep using it instead. One of the reasons why I am still with pre AC 3.2.1:)

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