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

            In the first image the vibration with the 3M foam sold by 3DRobotics, in the second i use home made antivibration system.
            There's no rule, many times an antivibration system works better than another, but only on a specific hardware.
            To achieve amazing results with the inertial system you must reduce the vibrations to your board, imperative!

            About Autotune: a good altitude where to perform the operation is about ten meters, not less, during this step the throttle stick correction is limited by the autopilot, like in alt-hold, it's not reactive as in Stabilize!


    • You got pretty bad vibrations and clipping going on.  I had the same funny altitude drop and it was the same thing.  I was running a Pixhack hard mounted causing the problem.  Not sure what ERR19-1 is though.

      • I think crippling came from landing. after 10 or 20 secs (not remember well) takeoff, landed for adjusting throttle hover slider. In my opinion; vibration is not the main problem. Also yes, i cant find any info about err19.

        If its barometric issue and it cant solved by code, an explanation of covering baro with special case or method will good for us.

    • I've found that when in autotune, it will loose altitude rather quickly when bringing it back to its starting area. The trick is to bring it back slowly (and add some throttle if necessary to maintain altitude). I've also noticed that the closer it gets to finishing the autotune, the more it will maintain its altitude when bringing it back to the starting area. 

  • Hello, I have the following problem.

    I have successfully flown my hexacopter on 3.2.1. I now wanted to upgrade to 3.3 RC9 because FrSky Telemetry should work there with X-Receivers.

    The upgrade went good, but I just can't get the accelerometer calibration done... I tried different laptops and even android to do it, but it always does a step over! For example, it shows "Place your autopilot leveled" I level the vehicle and press next. Then "place it on left side" is shown for half a second and immediately "place on right side" is shown, whithout me clicking okay?! I tried it over 30 times now and just can't get it done, which is pretty annoying :(

    I am using latest beta MissionPlanner!

    • I had Mission Planner do the exact same thing.  Restarted twice and now it works.  Strange.

      • restarted your Windows twice? Well, this is so strange oO. I have already restarted my computer several times and Mission Planner maybe 40 times.. Also tried reinstalling everything.. also android doesn't work.. Well it works now with the dev firmware and I was told to be fine flashing back to 3.3 and keeping my values.

    • You don't click next its press any key to move between the positions.

      • I already tried with spacebar.. still the same. Also why doesn't it work via android then? its also just pressing on the screen.

        I flashed some firmware from 25.07. (wanted to try RC8)

        Mission Planner shows 3.4-dev.

        Accel Calibration worked perfectly on this fw!

        I tried 4 different more recent firmwares before with no success.

        Can I flash 3.3 RC9 now and it will take those accell params?

This reply was deleted.


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