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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  • Randy,

     Should we expect SF10/C support for I2C in the next firmware release,

      if so, you wouldn't know the estimated release data?


    • Developer

      Hi Duffy,

      That's included in the 3.3.3-rc2 beta release candidate actually.  It was included in 3.3.3-rc1.  So feel free to give it a try and ping me here if it doesn't work for some reason.

      • Randy,

        my reply got truncated I think.

         But I installed the 3.3.3rc2 beta and install the SF10/C via I2C, made the changes in config but it doesn't look like it is producing any reading. sonar range and sonar voltage are 0


      • Thanks Rand

      • Randy: which modes works now with Lidar lite? auto is not include yet?

        • Developer


          No, I'm afraid Auto still isn't included yet.  Even if terrain following makes it into Copter-3.4 (we're going to try to include it) I suspect we won't get the google-map + lidar data mixing working until Copter-3.5.  It's a bit trickier than it first appears.

          • Thank's Randy. I'm not hurry I have to recive yet, install, learn to use, etc. only to know.

            • All altitude controlled flight modes work work well with LidarLite except Auto and Guided
              • Thank's Stephan

  • In 3.3.2 since we are logging more data now, would this be why I am missing a heap of camera trigger logs? I have 89 photos but only 68 cam triggers! Could it also be the fact that I am only using a class 4 sd card? I guess it is now safe to reduce some logging or try a faster card .. what do you say guys? I have lost some important  info on a mapping job today. Grrr..

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