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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          • Thanks I thought it might be on limits of the motor and props don't really want to go any more power or I'd loose flight time
        • My setup
          17x5.5inch props
          390kv motors
          30amp Simonk afro esc
          10000mah 4s
          Pixhawk 2.4.6
          Flys for half an hr


        • vibration levels abit high but there was a 23mph gust winds 

          vibration within normal levels on not so windy days


      • Will do but hopefully tomoz as is 11.10at night here lol so if it's not raining I'll try tomorrow cheers stuart
    • sorry missread where you said you covered the entire hawk in cling wrap and not just the baro :( 

    • you should NEVER cover the holes on the baro. Use dense foam not cling wrap.

      • Hi yes there is dense foam over the barometer in the pixhawk case
        • What Craig is getting at is that you said you cover the whole pixhawk in cling film, which is essentially the same as covering the holes on the barometer rendering it useless.

          • Oh sorry no I only covered with cling film over the top to stop wind blowing in directly it was no where near air tight or all around
            I still got height reading on mission planer
            Cheers stuart
  • I have done about a dozen flights now with V3.3 on my littlest Pix, a 320_mm hexacopter.  I had a few issues with the Autotune and PIDs on upgrade, but this thread has helped me sort those out.  Thanks boyz.  I have been pretty satisfied with V3.3

    But, today I have landing gear and a bent arm to repair. On my last flight, it inexplicably dropped from the sky.  I have tried to decipher the cause from my logs, but I don't have the experience to determine the issue. It felt like a voltage drop, but the battery had over 11_V remaining and the cells are within .1_V of each other.

    Can anybody suggest the culprit? . . . 

    2015-11-06 17-21-17.log
This reply was deleted.


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Aug 25