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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  • Good Morning,
    I have found a bug.
    Or at least I think so.
    I and 3 different Italian friend have found this probem.

    This is the Planner Screenshot

    This is the full parameter list.


    The Gimbal does NOT move when I change the CH6 IN PWM.
    I can move the potentiometer but the gimbal does not move.
    I have already tested the gimbal with a servo tester and it does move.
    And also if I change the servo MIN and the servo MAX PWM I can move the gimbal. But I can not move by using CH6 on the radio.

    I think this is a bug.
    With AC 3.2.1 this does not happen.

    • Did you put the CH6 Opt on the Config/Tuning Page to "None" ?

      I use Ch 7 and it doesn´t work unless i put CH7 Opt to "Do nothing".

  • Reuben, I migrated to M8N too from Lea6, I only put a cooper sheet little bigger than the unit, solder a ground wire to the cooper and plug in grn Pixhawk, I changed from 10 sats with Lea to 14 and them to 18-20 with the cooper but no extra config; did you check the wires? one time I had problems with a new one, good luck.

    • Hi Cala 

      I did make a small shield it was better but the main issue is high  velocity bar and positions Horiz errors on the EKF viewer.. the 7M seems better. when i get the Horiz error copter shoots off to some else ..  i have to be quick ...although once i let it continue and it did come back and continue the mission. Funny thing is the other machine is using a M8N no fancy mods at all  and has done over a hundred missions no issue ..granted it is not running 3.3.2. 

  • There seems to be a few of issues.

    1 being you are not waiting long enough after powering up to let all the sensors and GPS settle down before flying.

    2nd being you are flying too low and running a mission.

    3rd your craft seems highly under powered and is struggling to maintain altitude.

    • My trouble seems to be around this Horiz Variance message . . what is it where does it come from, gps or compass .. or accel's.?.I note i do see a volcity bar goo a bit too high once or twice in the replay too ?

      • I also use M8N from Drotek. I had to close a slolder bridge to switch it to 3.3V signal level. Did you change the configuration of the M8N according to the Pixhawk´s requirements?

        It looks like your GPS uses SBAS (GPS-Status 4). I would recommend to switch it off because it causes jumps in position when it switches to/from corrected mode.

        • Hi Hubertus  I have soldered the 3.3v bridge and i have tried three Drotek GPS units ..The SBAS thing is interesting as the Gps is supposed to be flashed with the correct config code when the pixhawk boots up. Even Randy has said in the past the config is sent by the Pixhawk so no need to do it manually ..Maybe i have a problem and its not doing it automatically, what test can i do to make sure its getting set by the pixhawk, can check baud rate and other settings by looking in MP while it all powered up ? 

          • shows how to go through pixhawk with ublox.

            Connection Option #1 – Mission Planner and Pixhawk as Passthrough

            So you can verify the default settings of your gps connecting directly with ublox and after that compare to the settings sent by pixhawk when you connect ublox trough pixhawk to gps unit

            • Hi Paul ..thanks .. I can do the Ublox thing ok, used to do it all the time with the old 6n units but only direct connection using ftdi unit not using MP (But have not done it with any M8Ns, I was not aware there was specific new config file for the 8,  I would like to Check the config in MP while GPS is running I know there is a comprehensive status messages you can look at ..i just have to find the right lines .. and which line tells me what info ... i guess i am looking for baud rate of 38400 and UBX ? these are the two main ones ..or others to check on...Also how to switch off SBAS?  cheers

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