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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      • Randy,


        Very good job!!!... really thanks.


  • HI Devs,

    Has something changed with MAVLINK from 3.2.1? I have a an app that works perfectly on an APM3.2.1, but on my PIXHAWK running 3.3rc8 it doesn't get the correct descriptions for the flight modes; although it will still switch them.

    Any thoughts?

    Cheers, Mike

  • I wanted to report that after using OF, the pixhawk refused to acknowledge the existence of a GPS device, as well as refused to output FRsky Telem on SERIAL_2. Had to reflash to 3.2.1 for normal, non-OF flight. Also, it seems that the ARM warnings (Accel, gyro, compass health) are all triggering for no apparent reason, even after re-calibrations. I will attempt to post dataflash logs and telem logs later. Just be wary that there are oddities after using Optical Flow.

    • could this be the issue with the telemetry?

      Note #3: set SERIAL2_PROTOCOL to "3" and reboot the board to enable FrSky telemetry like in previous versions.

    • Developer


      For the GPS issue, as part of setting up the optical flow sensor did you set the EKF_GPS_TYPE parameter?  If yes, maybe setting it back to "0" might get it working again.

      • I had changed the EKF_GPS_TYPE parameter back to 0. It failed to even show stats about the GPS, i.e. Sats, hdop, etc.... After that didn't work, I actually went one step further and used a beta param file I saved from before I configured the OF, when the GPS was working, and reloaded that. No dice. Even reflashing the firmware to the same beta firmware didn't help. The problem only resolved when I reflashed to 3.2.1. I will see if I can get the logs for you.

        • same thing happens to me when i use the 3.3 beta on PX4FMU  + PX4IO. it didnt see the attached GPS but resolved when i use 3.2.1 firmware.

  • 3702066209?profile=originalWay OT sorry. Couldn't resit. Still hoping for 'boat mode'. 

    • 3D Robotics

      "boat mode" coming soon! It will calibrate copter (and Solo gimbal) on moving vehicle.  Dynamic home location (for moving platform) and GPS position-hold loiter optionally replaced by alt-hold, to ensure that the vehicle doesn't zoom "backwards" trying to hold a static position while you're on a moving vessel. 

      • Although I am sure you probably are aware of this already, here are some guys who have already implemented "Boat Mode" -

        From what I can tell it works basically like this...

        1. You arm you bird on a nice level surface on the mainland.

        2. You hop on your boat, switch to "boat mode" - which loads the last values of the gyros, i.e. the ones you got in step 1.

        3. You take off in Alt-hold - for obvious reasons.  Switch to loiter up in the air if you want.


        Boat mode: take off from a boat
        Sometimes drone users wish to be able taking off from a boat. Even for very large ships, a boat is somehow always moving. Before starting to fly…
This reply was deleted.


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