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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  • ArduCopter 3.3 rc8

    What is the correct value to put in FLTMODE1,2,3,4,5,6 for obtain Auto-Tune-Flight-Mode?

    I see that:
    0:Stabilize 1:Acro 2:AltHold 3:Auto 4:Guided 5:Loiter 6:RTL 7:Circle 9:Land 10:OF_Loiter 11:Drift 13:Sport 16:PosHold

    Maybe autotune is 8, or maybe 12, or 14, or 15?

    I know that you can not do by using the GUI in the planner, but you can only do by editing the "Full Parameter List".
    I also know that I can set AutoTune by CH7. But I do not want to do it by CH7. I would like to test it by using only a 6CH radio.

    • It is not a flight mode at all. You need to set it to either channel 7 or channel 8. oh looks like it is possible now with 3.3 and the new MP

      • Developer

        Yes, that's right.  It is actually a flight mode in AC3.3 (in AC3.2.1 it was not a flight mode).

      • It uses a flight mode.  Initially, setting the flight mode directly didn't work correctly as some required initialization and cleanup wasn't done but that was fixed a while back.  I haven't checked lately, but last time I looked, this needed better documentation in the wiki.  It is important for people with 6 channel radios to be able to set it up this way.

        One small restriction with using the flight mode switches;  I believe you need to arrange the flight modes so you can go directly between altitude hold and autotune modes without a third mode between.  For example, if more than one switch is used to select flight modes, you need to be able to switch between autotune and altitude hold by changing just one switch and if it is a three position switch, one of the modes must be the middle position.


    • Developer

      It should be possible to do it using the MP's flight mode setup screen now that we've added AutoTune to the parameter descriptions.  In any case, it's "15"

      • Randy, Thank you very much for your reply. I had just reinstalled the MP to make sure that I had the last version. Actually I have the version 1.3.31 and the Flight Mode AutoTune do not show up on the Flight Mode list. And also is not mentioned on the Full Parameters List. Attached the screenshot. Should I have to open the issue on Mission Planne GitHub? Another question: The ESC calibration method is changed on AC3.3 rc8? I



        • Sorry for double message.

          I have some browser problem in editing the last message. I'm very sorry =(

          I re-write evrything here:

          Randy, Thank you very much for your reply.

          I had just reinstalled the MP to make sure that I had the last version.
          Actually I have the version 1.3.31 and the Flight Mode AutoTune do not show up on the Flight Mode list.
          And also is not mentioned on the Full Parameters List.

          Attached the screenshot.

          Should I have to open the issue on Mission Planner GitHub?

          Another question:
          The ESC calibration method is changed on AC3.3 rc8?
          Can I calibrate the ESC in the same way I do with AC 3.2.1?

  • Hi Brad,


    Are you using two (2) GPSs , or only One ?


    Because I had similar problems last week (Pixhawk Platform) with 2 GPS, but I don’t have more the logs.


    Then I "remove" one GPS ("without brand" . generic one ). and test again and again, without any problem.

    • Just one GPS


      • with only 1 gps system is very dangerous to fly. I had to put 2 gps units for this reason alone, as it is highly unlikely for both healthy GPS units to glitch with data transfer simultaneously. both vehicles I have are flying very reliably with dual gsp setup. without it - it would do a similar uncontrollable slip out sometimes, same as you saw.

        only downside with 2 GPS units is when signal is not good and one gps get replaced with an another your drone may 'jump' to the different location and then back, as it thinks it got moved as different gpc units receive slightly different coordinates.

        but it is a minor issue, and I do not think any system on 3.3 should be operated with a single GPS, as long as code is what it is.

        Randy stated above drone is expected to land - it does not. it will go sideways as described, with crazy speed, and you need to have a motor kill function ready to stop it from a fly away. it never happened to me after I got dual gps setup done.

        PS. Perhaps, for a dual GPS setup it would be nice to augment the code with some analysis of what coordinates each GPS unit reports and prevent this position adjustment done with a presumption that drone suddenly teleported itself from an old location into a different one.

This reply was deleted.


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