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


          Ah, thank you very much for that.  As mentioned over there, I think the best idea is to try and get either the MAVLink or Serial protocols working instead of introducing a 3rd protocol to control the gimbal!  Two protocols is surely enough!

      • I also got this board and so far unable to make it talk with AUAV board.

        I know storm32 board can be also connected via SBUS - how can it be done exactly if serial connection does not work out?

        Also, what and how can be done to make serial 4 port to appear? I understand serial 5 is by default mapped into output, but can be swapped by serial4?

      • Yes thats exactly my problem. Sorry for my poor explain

  • I have been trying to get my hex back up in the air but one thing that I was hopeful to use in this new firmware is the sbus output. I have enabled the parameter as directed on drones discuss but I don't seem to be getting any output from my pixhawk. I need to be able to run the sbus out to control my alexmos gimbal pitch ,yaw, and shutter control. The alexmos picks up sbus from my receiver if plugged in directly so I do know that the alexmos isn't the problem, but there doesn't seem to be any sbus output from the pixhawk on any of the encoded sbus channels. Is this functionality supposed to work in 3.3?
    • Found my issue. It seems that the sbus output doesn't enable until the safety switch is armed. Once armed, it seems to allow sbus out for output channels 1-8. It would be nice if sbus out would work without pressing the safety switch.

      What would also be nice is to have additional channels in sbus out. For a hex, I only have 2 channels not tied to escape outputs. Channel 8 out easily links with my camera pitch control, but I also need a pass through for my camera shutter. If I am using the rc in channel 7 as an auto tune trigger, but not using the channel 7 output, is there a way to pass, say, channel rc 10 in out to channel 7 so that I can control channels within the current sbus out limitations?

      I guess I can use channel 7 as a pass through and one of the higher channels as an auto tune trigger. Not ideal but it will work.
    • 3702577530?profile=originalHi, I tested my Hexacopter with 3DR Pixhawk and 3.3 RC 6/7. Everything is OK, but when I look in the logs than I see always red lines: Error EKF Check -2 and Error Check - 0.

      What is the reason for this???? During the flight I have always between 16 and 19 sats and HDop until 1.1

      • I forgot the logs:


      • Developer


        This means that the EKF is unhappy (at least temporarily) probably because the compass + gyro or accelerometer + GPS data does not agree.  In your vehicle's case it's got a "-2" followed by a "-0" very early in the mission.  This means the error occurred but then cleared so I wouldn't worry to much.

  • It is weird - i ran autotune again today and my hex developed some sort of a vertical jerk tendency when i give it yaw movement, i simply rotate it with a left stick and it does little jumps up and down, may be 3-4 inch most, then during loiter it may do some similar movements, i do not remember doing it before.
    As it never did it before i ran an autotune again but it did not go away.

    I do not want to erase all parameters to default - what parameters should i adjust before running next autotune? Or does it even matter for autotune code what initial parameters you have?

    I looked at vibrations - it did not change from what it always was, z axle is under 15, x and y are under 8. So it should be good. Yet it is not, drone is not silky smooth anymore and i do not get why it changed.
    • I think i figured out what parameters did this. I dropped all to default, will do autotune tomorrow and will compare what will happen.
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