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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  • Sad to apm2。

  • You will need to solder 3-pins of a DF13 6-pin cable to the gimbal controller board as shown above and then plug the other end into the Pixhawk’s Telem 2 port (from Copter 3.3 it should be possible to attach the gimbal to any of the available 6-pin ports)

    Found this on storm32 Page@wiki

    Can somebody explain the (from Copter 3.3 it should be possible to attach the gimbal to any of the available 6-pin ports) function? Should this work or will this work? Is there a change in how the serial ports can be used?

    • To be more specific... This passage reads like I will be able to map storm32 to serial5? No dev can tell something about this?

  • Hi Randy,

    I'm testing 3.3RC1 using PIXHAWK and PX4FLOW,

    In the release notes, you mentioned "PX4FlOW support in Loiter mode",

    However, I just failed to switch into loiter mode indoor.

    Can the flow sensor be used without GPS-lock?

    Thanks advance for your reply.

    • Developer


      Yes, it can apparently be used without a GPS lock but only Paul Riseborough knows how.  I know he's planning on writing up a wiki page but he's knee deep in EKF investigations around AC3.3.  I'll ask him to post the parameter changes here if he can.

  • Trying to take advantage of the new retractable landing gear features. Running a Chinese retract set on a 600 hex on a camera rig.

    Any tips/suggestions on how to configure the wiring and parameters? In lieu of the gear mode is there a simple pass thru I can use to control the gear?

    • Look few pages back.. The dev already wrote a description

      • Yep, here:

        • I have read Rob's comment but I am not clear whether the gear will deploy only in Land or RTL with throttle failsafe or will the gear deploy with Land or RTL regardless of failsafe condition..?

          • It should deploy regardless of failsafe.  But it does NOT deploy based on altitude!  It only deploys in Land mode, or the final stage of RTL (which is basically land mode). 

            If you are landing manually in Loiter mode, it will NOT auto-deploy.  Nor will it auto-deploy if you are RTL'ing into a hill, etc.

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