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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                  • Should have said APM P2 sorry my mistake. 

                  • I got you now but it really doesn't seem like it in the text... 

                  • We are referring to APM Planner 2.  Mac OS GCS

                • I had the same problem with APM2.  Just reload with the latest beta APM Planner and it should work fine.  It is an APM planner issue that has been addressed.


                  • Yes your right that corrected that. Great!! Thanks...

                    But..... my teensy lua script no longer works. Bummer.... very handy. No GCS needed. Not sure where to look to address that problem. I did set the  SERIAL2_PROTOCOL to "3" as suggested. The X8R receiver is getting telemetry just no data from the pixhawk it seems. 

                    Now if I get DCM bad heading I won't know... sweet!! Fixed!! LOL 

                  • Excellent thank you I will try that. 

                • went back to 3.2 seems fine. I highly suspect it's APM2... guess I'll post over there and see if Bill has any idea's.

                  • I remembered having problems with the teensy mavlink and went back in to check on my machines.  I ended up setting SERIAL_2 protocol to 2 instead of 3 on all three of my copters and they continue to communicate to the transmitter through all the 3.3 progression.  This was just trial and error on my part, not even an educated guess but it works.



  • My quad has been running 3.3 rc4 for probably 2-3 hours with no real issues, including no 'bad gyro health' warning. Yesterday I decided to reset the parameters and re-calibrate everything because I had made a few changes and wanted to see if Auto Tune produced different results.

    Wow, all heck seems to have broke loose. I installed a new GPS, but it had errors before doing so. I'm not sure if this one was there before the new GPS:


    There was another EKF error "Error EKF POS VERT AGL" and now I get 'bad gyro health' constantly.

    I think it may be time to wipe the sd card and start over, but odd it had been running so well. 

    The external compass on this new GPS has high offset on x (not used to seeing >75) and internal has been high since installing the AUAV-X2. I'm thinking it's picking up noise from the power wires underneath, not sure yet?


    • Developer

      The "Error EKF PRED.." thing is a mission planner issue related to how it's displaying new information from the EKF.  I hope that will get fixed shortly but I don't think it requires a change to arducopter.

      The "bad gyro health" issue has been resolved in master and will go out with -rc5 which should be out soon.  It's a timing issue so it can come and go.. it could be that the new GPS is causing jitter in the main loop which would lead to more of these bad gyro health messages but I'd need to see a dataflash log.

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