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


        Thanks for the report.  I'll bet that's caused by the slight change in the shape of the pwm->thrust curve.  If you'd like to confirm (I'd kinda like to know actually) you could try changing MOT_THST_EXPO from 0.65 back to 0.50.

        • I changed MOT_THST_EXPO from .65 to .50 as requested. The motors would not spin until MOT_SPIN_ARMED was at 75 so that change didn't have any effect. Fortunately I was using a GCS at the time this first happened and appreciated that the craft was armed even though the props were still.

          I tried to look at the log file for this session but it is 178mb and crashes Mission Planner (or overstresses my PC) whenever I attempt to load it.

          I also accidentally powered up the copter and armed it without a SD card installed with no warnings from Mission Planner. I feel sure I got a warning last time I did that.

          • Edit. I just changed another copter from -rc9 to -rc10 and the motors spin when armed without adjusting any parameters.

    • Hi all.
      With 3.3 RC9 firmware I have problems getting storm32 (firmware v80)to work while connected to pixhawk serial 4/5.
      I have used following user guide to setup both strom32 and pixhawk:
      Below are detailed settings I applied to pixhawk:
      SERIAL4_BAUD = "115"
      SERIAL4_PROTOCOL = "1"
      MNT_TYPE = "4"
      MNT_RC_IN_TILT = "6"
      On storm32 side I have only enabled emit heartbeat.
      Above settings should allow me to control gimbal pitch with rc channel 6, but nothing happens when I use channel 6 knob on my rc transmitter.
      Can you let me know if by the chance this issue is resolved in lates RC10 beta?
      Or maybe there is some configuration I have missed?
      Can anyone confirm that communication between storm32 and pixhawk serial 4/5 is actually working?
      Both telemetry ports on my controller are used so serial 4/5 is the only I have.
      • Hi,

        I don't have a STORM32 board, but, in case you missed it, there is a bug fix in 3.3 rc10 for STORM32 serial protocol driver.

        • I have a Storm32 board and the issue with the serial protocol is defenitly not fixed in RC 10.

          The only option is to downgrade Storm32 firmware to < 0.78.

          Maybe some features work but the channel control (Yaw or tilt) does not.

          • Developer

            No promises on the serial interface working but the MAVLink interface should work although I have not tested it really recently.

            • I've tested it - none of the rc channel control code was changed. I can confirm all serial mode features work. I haven't tested the gimbal in mavlink mode.  This is with firmware .86e & 3.3rc10. Make sure you set the gimbal mode to rc control, the easiest way is to change the default mode to rc targeting (MNT_DEFLT_MODE).

              • I found my mistake: From the wiki it is not clear if we must disable the mavlink heartbeat for using serial protocol. With the older versions it works with the enabled mavlink heartbeat. But with the newer storm versions you must disable it to get serial protocol working. Maybe the serial setup should be explained a little bit better in the wiki.

                Many thanks


                • Great you found your issue. About the Wiki though, since it IS a Wiki you are free to sign up and make edits which frees up the devs time to actually do devvy working you know. Just saying.

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