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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          • Would be great to use it on Serial5

    • thanks Randy :) Thanks to all the developers!

  • Hi there,

    I think, will Copter 3.3rc-2 be released on tomorrow. I have found some detail about it ;) 

    Changes from 3.3-rc1
    1) AutoTune reliability fixes (improved filtering to reduce noise interference)

    2) Optical flow improvements:
    a) Range Finder pre-arm check - lift vehicle between 50cm ~ 2m before arming.
    Can be disabled by setting ARMING_CHECK to "Skip Params/Sonar"
    b) Vehicle altitude limited to range finder altitude when optical flow is enabled

    3) AltHold & Take-off changes:
    a) feed-forward controller and jerk limiting should result in slightly snappier performance and smoother take-offs
    b) vehicle climbs automatically to PILOT_TKOFF_ALT alt when taking off in Loiter, AltHold, PosHold, Sport (disabled by default, pilot's throttle input overrides takeoff)
    c) PILOT_THR_FILT allows enforcing smoother throttle response in manual flight modes (defaults to 0 = off)
    d) TX with sprung throttle can set PILOT_THR_BHV to "1" so motor feedback when landed starts from mid-stick instead of bottom of stick
    e) GCS can initiate takeoff even in Loiter, AltHold, PosHold and sport by issuing NAV_TAKEOFF mavlink command

    4) Stop flight mode - vehicle simply stops and does not respond to user input

    5) Aux channel features:
    a) Emergency Stop - stops all motors immediately and disarms in 5 seconds
    b) Motor Interlock - opposite of Emergency Stop, must be on to allow motors to spin motors, must be off to arm

    6) Air pressure gain scaling (of roll, pitch, yaw) should mostly remove need to re-tune when flying at very different altitudes

    7) landing detector simplified to only check vehicle is not accelerating & motors have hit their lower limit

    8) Loiter tuning params to remove "freight train" stops:
    raising WPNAV_LOIT_MAXA makes vehicle start and stop faster
    raising WPNAV_LOIT_MINA makes vehicle stop more quickly when sticks centered

    9) Other items:
    a) faster EKF startup
    b) Camera control messages sent via MAVLink to smart cameras.
    Allow control of camera zoom for upcoming IntelEdison/Sony QX1 camera control board
    c) Lost Copter Alarm can be triggered by holding throttle down, roll right, pitch back

    10) Bug fixes:
    a) Home position set to latest arm position (it was being set to previous disarm location or first GPS lock position)
    b) bug fix to mission Jump to command zero

  • Last night, I upgraded to AC 3.3 (compiled from master).  I calibrated the accelerometers.  I can arm and the Iris+ responds to throttle, pitch, roll input from the transmitter (props off).  The problem is that on my transmitter, I no longer get updated values for Sats, Battery Voltage, Flight Mode, etc.  All show 0 (except for flight mode, which shows Stabilize).  I can change flight mode -- the drone responds with a beep when I move a mode switch -- but no change in the display.  I reverted to 3.2.1 and, as before, the values update properly.  I then installed 3.3 downloaded via MP.  As with the version I built, the flight data values are all 0. I didn't see any other mention of the issue in this thread so I assume I'm doing something wrong but I don't know what.  Thanks.

    • Got an answer from devs on another forum.  Needed to set SERIAL2_PROTOCOL parameter to 3.

    • I'm guessing there might be Mavlink changes that broke any telemetry conversion parts of APM or any other seperate converter (remember those are not supported by the APM team), so the dev of the converter code might have to take a look at it.

  • I'm trying to configure 3.3-rc1 to take advantage of the new gimbal control features with my alexmos 8bit board running 2.3 on a DYS gimbal. Excited about trying out the do-mount commands.

    After hours of fiddling I can't get the gimbal tilt control to work at all via RC10 (aux 2) and remote input via RC6 via setup in the latest version of  mission planner.


    Testing using an analog servo and I can't get the servo to move using inputs from the remote. I know the servo rail works because I have a retract setup on RC9 (aux1) and it works fine.


    Any suggestions/tips on getting the pixhawk to output gimbal tilt signals either from the mission or via the TX?


    thanks, robin

    • Read some posts back and you wil find the solution.

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