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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  • Had a few flights now with 3.3 RC12 , everything seems pretty solid and I'm very happy with the way my hexa flies with it. Thanks to the developers for all the work that has gone into this release. Nice job!

    Only thing I'm having a problem with is the new retractable landing gear support.  I followed the instructions in the wiki and using the switch on my Taranis I can manually retract and deploy the landing gear, but I was expecting the gear to activate automatically (with my gear switch in the middle) when taking off and landing but nothing happens, it just stays in the last position selected by the switch (up or down).  Have I missed something? Is there a parameter to set the height at which it should activate? Does the middle switch position PWM value need to be within a specific range to work?

    • Hey Horsj

      As I understand it, the landing gear won't activate (as in retract) automatically - that's something that should be corrected on the wiki - but it should deploy automatically either if you choose landing mode or if it goes into a landing mode in any automated mode (auto or rtl).  I don't think the middle switch position matters at this point, in my experience it's either on or off, and the auto deploy should still work in 'on'.

      • Thanks Fnoop Dogg.  Yes, it would be useful to have the wiki updated to clarify the functionality and under what circumstances the auto-deploy is activated - it will save some head scratching.  I'll test it with RTL, but I think I'll try it with my camera and gimbal off at first  ;-)  Cheers!

  • Moderator

    Noticed a couple things using the latest 3.3 rc1x, I'm flying a small carbon tricopter with the AUAV-X1 flight controller.

    1) ResetToArmedYaw (CH7/8 option) doesn't work, info from a search reveals it has never worked, is there a plan to get this working? (it's not quite the same as Simple mode)

    2) Autotune weirdly doesn't seem to work for me, I've set AUTOTUNE_AXES to 4 (to tune yaw only) but when in ALT_HOLD and I switch CH7 (Autotune) to high nothing happens. Is this tricopter specific?

    3) The loss of altitude problem in ALT_HOLD forward flight is very noticeable on this airframe (not in this log), however to clarify this and to hopefully add to it's understanding, there is no loss of altitude DURING the actual forward flight, however the loss and recovery only occurs AFTER the pitch stick is released and the copter is drifting forward while level, it's almost as if the altitude controller can't catch up properly or overreacts to the sudden change in attitude?

    Log attached (two attempts to autotune and one to ResetToArmedYaw)


    2015-10-04 10-06-33.log
    • Developer

      Hi Graham,

      The reason Autotune won't start is because you have not centred your throttle stick. You are asking for an altitude change and it is pausing auto tune until you centre the throttle stick.

      • Moderator

        Thanks Leonard, what value center throttle is it waiting for? My throttle in was 1583 for the first one, is it looking for exactly 1500?

        • Moderator

          Had lowered the throttle deadzone so center throttle was more elusive than necessary, thanks again.

  • I've got a lot of kinks out of my setup now.

    3.3 and Tower beta release play very nicely together. Tested 'Follow Me' this afternoon. and got the Hero4 Gopro slung on the FeiYu 3d Mini gimbal for the first time. Just downloading the video to see how it handled things but first impressions are really good.

    Muppet here was testing circle mode and the vehicle just clipped a tree. Explosion of leaves and twigs, airframe tumbled out of tree at least 90 degrees rolled over, lost about 2 metres altitude. Flattened out and ........... stabilized. No harm done!

    Now if I can get Airborne Projects to update their Mavlink and the Lua Scripts I can go back up to OpenTx 2.1.3!

  • AC 3.3 RC12 - I'm doing some advanced tuning to certain parameters and need guidance on what values I should use for the following- I searched around and could not find guidance on how to tune these parameters for my specific build:

    MOT_THST_EXPO (default is 0.65)

    MOT_THST_BAT_MAX (default is 0 - do I just put 4.2 x 6S cell count = 25.2? )

    MOT_THST_BAT_MIN (default is 0 - do i just put 3.3 x 6S cell count = 19.8? )

    MOT_THR_MIX_MAX  (default is 0.5)

    MOT_THR_MIX_MIN  (default is 0.1)

    MOT_YAW_HEADROOM (default is 200)

    Quad specs: 6S lipo, 17x5.5 props, 5010-14 360kv, 2480 AUW, 30% THR_MID

    • Developer

      Hi Kurt,

      That looks very good. In order to do better than that you would need to give me the throttle curve of that particular propeller, motor, esc combination.

This reply was deleted.


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