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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      • Did you have to change any of the defaults to make the x8r and lua script work? Thx

  • Randy or leonardthall, I would like to attemt an autotune on my big tricopter tonight with AC3.3rc4 and while going through full parameters list I noticed autotune axis parameter. In my case it is set to 7, is this because servo is plugged in ch7 output? or is that a bug?  Just to want to clear this last doubt away before proceeding, thank you! 

    • Moderator


      Autotune_Axis_Bitmask is used to define the Axis/Axes you want to tune during the Autotune cycle. A setting of "7" means it will tune All axes (roll, pitch and yaw) during this cycle. See the explanation here for a full list of settings possible.


      Nathaniel ~KD2DEY

      • Thank you, I was not aware the wiki ninjas were this fast! 

  • Flight Test Report - Comparison of 3.2.1 and 3.3 rc4

    I did a comparison test of my aerial panorama mission in 3.2.1 (Mission 1) vs. 3.3 rc4 (Mission 2):

    1. Both missions were nominal (takeoff, mission execution, and landing)
    2. 3.3 rc4 generated the following error messages repeatedly:
    • Error EKF POS VERT AGL
    • Bad Gyro Health

    There were no error messages using 3.2.1

    I don't see any of the error messages in the dataflash logs but they do appear in the tlog when I play it back. Links to the logs on Dropbox are below.

    For the two tests I used my 680 class hex frame equipped with a 3DR Pixhawk and 3DR GPS about one year old. I used Mission Planner 1.3.25 to monitor the flight. EKF was turned on for both flights.

    After running Mission 1, I used MP to load 3.3 rc4, did the Accel calibration and set the MOUNT_TYPE parameter to "1". If there are any other parameter differences between the two flights it's not something I did.

    Both flights were identical in the same location with similar weather. I took off in stabilize, got up to about 20 meters and switched to Loiter. I did a couple of roll and yaw inputs just to check stability and then switched to Auto. The mission ran to completion and then did an RTL. The mission takes a series of photos at different yaw angles and varies the pitch of the camera gimbal as needed to get the required number of rows of images. The RTL worked perfectly in both missions. As soon as the hex touched the grass I switched back to Stabilize and disarmed.

    I don't understand why the errors aren't in the dataflash log (or am I missing them)

    Hopefully this helps.

    Mission 1 DataFlash

    Mission 1 tlog

    Mission 1 rlog

    Mission 2 DataFlash

    Mission 2 tlog

    Mission 2 rlog

    Dropbox - Link not found
    Dropbox is a free service that lets you bring your photos, docs, and videos anywhere and share them easily. Never email yourself a file again!
    • I am also getting messaging Error EKF POS VERT AGL and occasionaly BAD GYRO HEALTH, and with blinking green led, arms and flies great.. 

      However, If I turn off tx, the Error EKF POS VERT AGL goes nuts flashing and voice every second..


      MP 1.3.27

      EKF on

    • I'm getting the EKF errors as well

      Other than the bad gyro health it appears to running ok.

      I did have some weird behavior like one of the motors not running at all on my hex and the pitch channel getting reversed that was cured by reverting to 3.2.1 and then reflashing 3.3 RC4. At first I thought it was an ESC or motor issue after an hour of ruling that out, reflashing cured it.

  • Thanks Doug Walmsley for your information about Lidar as I'm getting close to pulling the trigger for one. 

    Question: Can Lidar be turned on/off during flight either by radio or auto mission etc.? 

    • Just a note here, CHx_OPT=10 parameter does not appear to control PWM connected Lidar (obviously not switching it off)
    • I believe if you set RNGFND_MAX_CM to 4000, it will shut down saving 100ma of power when above 40 meters.  Once the copter descends below this altitude in centimeters, then the LiDAR unit starts taking readings.   I suppose you could install a power switch/relay that can be triggered to terminate power to the LiDAR unit via pixhawk or receiver channel you choose to use.  Not tried this option, but I do know the LiDAR stops taking readings when I go above 40 meters.  I do not know of a option to turn on or off the sensor via auto missions.

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