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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  • Hi everyone,

    I was enjoying 3.3.2 but suddenly had crash  :( . I think one of the motors/prop/esc just stopped at ~55m and then just saw it falling 

    Could you please help me figure out what happened ?

    Log here:

    2015-12-25 16-56-49.bin

    Dropbox - Error
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    • Anyone kind to take a look please ?

      I cant really figure out what happened. It was fine before 3.3.2...

      • it looks a mechanical failure in motor 3, check it


        • Thanks for taking a look Cala.

          It also could be #4 right ? and 3 tries to compensate ?

          It is for sure the motor or could be the ESC ? 

          coincidence or not the ESC #3 got pretty damaged upon hitting a wall (some capacitors and a few other components were gone), it could also be the case that it was this one that caused the fall and coincidentally the one that hit the wall, right ?

          I've bench test all the motors / and the three esc's remaining and everything works. 55m fall and not even a single propeller broken (damn APC propellers are made of steel ahah)

          • For me motor 3 is the problem, I'm not an expert but if I'm incorrect anyone else shure correct me watching the graphs. esc can be the problem too but a pitty that you can't test it. If you can't find nothing, repair it, test near the floor and then read log if you notice any ERR message, check connections and wires too, looking for any little damage. 

  • hey there, I have a 250 sized quad running AC 3.3.2 on a PX4mini board by airbot, there were couple of compass related issues which I think I've sorted out, however when I attempt to take off copter starts spinning around itself very fast (keeping horizon though, kudos devs!) I've tried to determine what's the issue is but as far as I see from the logs there are no errors and RCin4 corresponds to actual stick movements. Can someone take a look at the log below to help identify the issue?  

    p.s. log is from AC3.3.4dev but the quad behaves the same way on AC 3.3.2 

    2015-12-28 22-47-36.bin
  • Finally the rain and wind stopped! Did some flying with 3.3.2 and saw some weird behaviour. I occasionally get these huge spikes in ErrRP, ErrYaw and EKF SV & SP. Haven't seen these before that I recall. A couple of flights show these the rest do not. The flying conditions were calm and the copter behaved well in flight, but these spikes seem bad. I can't find any correlation with GPS glitches, high vibes, mag interference or any of the usual suspects.

    [Note to Leonard, I also tried some 5045BN's for the first time and needed even greater divergence between P&I on both Roll and Pitch for stable flight. I've pretty much given up on autotune for this copter at this point. The attached log is for 5030's however.]



  • I think this is the correct one.

    Sorry if in the previous post I had attached the wrong one.

    2015-12-29 10-17-22.bin

    • Hello Andrea,

      I had a quick look at your log and it seems that you have a problem with your center of gravity, you have your rear motor pushing harder thant the front one. Check if your copter is balance, and then verify that all your props are in the same alignment.3702609766?profile=original

      I made tests with bad motor mounts alignement and I had a CW/CCW bias that ended by yaw drift with throttle change and a small loss of stability during heavy yaw command. Here are my motors outputs before/after proper alignment to get all props in the exact same plan:

      3702609805?profile=originalOf course, after alignment I had no more yaw strange behaviour. I hope this may help you to fix your copter.

This reply was deleted.


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