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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    • Developer

      Hi Vic33,

      After autotune you should land and disarm then take off and fly again to test the pids. You can also test them by moving the autotune switch back to the off position and back to the on position. Be careful though as a bad tune may need you to quickly switch back to the the off position.

      • Thanks leonard,

        But i know that, as i don't make a autotune every days, just before i had a look on the process to refresh my memory, and i'd choose the second method, that why i surprise, at the end of the process i'd turn off auto T , then switch on.

        it's could be me that dreamed, or due to my 3 position switch (taranis) for autotune that i'm not full turn off by just put it meddle position? even if auto tune on/off is confirm by MP in my workshop...

        Don't be affraid, i'm used to pilot, i've 9 years of flight experience on this type model (multirot), and i have the chance to have a great area test zone with about 2m height of reeds for the "dangerous" test, moreover as it's dev quad, if it crash i'll don't cry ;-) 

        • Developer

          Hi Vic33,

          No problem, thanks for your feedback and help!!

          • you're welcome.

            my only regrets is that I've no skills in coding :-( 

            and a poor English ;-)

  • Developer

    I've updated the Warning #1 to tell people to hold off on trying AutoTune until -rc2 comes out which will include some fixes from Leonard.

    • Hi Randy,

      Wasn't auto tune supposed to be repositioning during the tune phases, incase you experience drift off due to wind influences.

      I thought I did see this in the asome video of Marco where he did test the auto Tune?

      Just flew into a tree during auto tune, as the last phase (the yaw tuning) is changing the orientation, and getting it back when the Front of the hex isn't where you expected it to be, makes it a little harder to stear away... (Pure operator error, as the autotune did go fine)

      Unfortunately by hitting the tree it dropped into a pool of water, so using an airblower now to dry it out, taking every component apart..., I could get it out of the water in just seconds, so hopefully no expensive parts lost (did lose a motor / esc, which was smoking when I got it out)

      Log is available incase Leonard needs it.
      • Developer

        Hi Erik,

        Oh, that sucks!!

        No, it doesn't hold position yet. I have it planned for the future but I will get the basic functionality in there first. I will also look at alt hold tuning as well.

        The copter should hold it's heading during tuning.... The log would be helpful, thanks!!

        • Yeah, but you need to experience everything ;-(

          Tune looked fine, except I did see very minor altitude jumps, of 30, 50 cm every now and then during the roll and pitch tuning..

          I also did see that it is not alternating like it did before (with v3.21)

          So in practise this means that you can have a right move due to the roll, followed by another right move, and so on.

          Before you did right, left, right left, and that kept the copter more at one spot in the air (obvously depending on wind drift)

          Same on Pitch, where it keept moving away by dipping the front more for several instances.

          You get the picture, it should be visible in the log as well.

          Good luck, you guys do asome work on the software if I see the number of fixes you all handle on Github (get a mail on every change, just to see what is improved... ;-)

          Ok log in the next one, as it was just over the 7 Mb sizing limit

          • Including log now...


        • Developer

          Sorry the adjustment to hold the yaw heading will be in the next release. Sorry!!

This reply was deleted.


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