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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      • Here is a short overview of todays log for the 2016 version of the "FPV Hexaracer",

        (The only thing i was changing from 2015 are the motors from KV1800 to KV 2050)

        This thing is crazy fun.

        Some Facts :

        Peak Current : 180Amps

        Peak Climbrate : 23-24m/s

        Peak Speed (GPS) : 29-32m/s


      • Hi Paul, i'm currently not up to date concerning all the new features, the development really brings this project to news levels. But i'm with you, the copter is very well balanced and all components have been selected and tested over years to become reliable. Now i'm there were the copter has become reliable. Somewhere in this forums the should be some pictures of the build

  • Hi I need help with my Hexa on AutoTune

    Hexa with 3.3.3 fly ok with default params no issue.

    wanted to have smooth settings and done Autotune.

    After Autotune is done and params are saved, Hexa Oscillates even on ground when arming and bit THR up.

    Tried this twise by resetting all and running another Autotune, but with same results.

    Can someone please help ?


    • did u run autotune and connect with telemetry and pc when autotune ?

      • I run autotune and connect with telemetry to my phone running tower for monitoring.

        log files

        • Autotune is not the perfect tool, it depends on the wind, vibrations, type of frame, etc.

          My best experience with different frames is manual tune by tethering and in flight with the Ch6 manual tune tool.

          • It worked before with same setup on Copter 3.1

            I don't have earlier pids but will test it maybe without yaw.

            • I had a look on your log from November 26, 2015

              Is that same copter? PIDs seems OK, reacting quite well. It was overpowered at that log, powerful, but without load.

              It is not good idea to tune large platform without the weight that is designed for. Can use dummy weight.

              Last log shows huge oscillations, caused by wrong PIDs. The autotune gives bad results, probably due to the overpowered copter  - average ThrOut is 350.

              Can you advice what is the frame, details, photos?

              • I can propose to test the following parameters:

                Stabilize Roll 8, Stabilize Pitch 6, Stabilize Yaw 4.5

                Keep the Rate Roll and Pitch PIDs from the last autotune.

                Put Rate Roll/Pitch both Imax 1000, 

                Rate Yaw P 0.2; I 0.02; D 0  

                • Thanks for your help.

                  Had crazy week, but did some testings today.

                  Lowered settings and i'm now vibrations are gone.

                  still need to retune the system to better stabilization.

This reply was deleted.


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