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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      • Hmm yeah it is using a GentLED to trigger. Wonder if it somehow double triggered via IR, but it's all set to manual focus & no review, so it triggers pretty much instantly when it gets the signal and is good to go again quickly. I've taped the LED to the IR window and covered it over so there's no external light that can get in and mess with things. I never had any issues with image #/log mismatches on 3.2 with this same setup, so I'm wondering if it might be something else.

        • I haven't been able to geotag images for a while, on 3.2 or 3.3. I can't even find any cam_trigg messages in the log. I managed to tag in Mission Planner once recently using time difference but it came out a bit odd (registered all the photo's as a single line). Pix4D doesn't recognise the logs either. I use a relay type usb trigger on an s110.

          • That's really odd.  I've been mapping with 3.3 since it was released and after fixing the offsets in the geotag window.  But even when the Mission Planner geo tagging wasn't working, Pix would work.  I'm back to MP to geotag as it's more accurate (not really that big of a deal) though.  


            • I'm sure it's something I have or am doing wrong,

              • Send a log file to Pix4d, they'll get you going again.  Nothing worse than not being able to work.  There's still a 90 degree kappa angle error when using Pix4d though.  No big deal, again just don't select high precision if you're using 2.0 Pix4d mapper.  Earlier versions don't matter.

      • What are you using to trigger the camera?  Gent led and other ir triggers are problematic at best lol.  I use direct multiport on a relay output, never miss.  If you can't match them up and you're using Pix4d, their geotag function will work.  If your geolocation is off, just don't select high precision.  Won't effect your precision, it just takes longer to process.

    • Based on the numbers you list, there are 16 fewer images than triggers.  This seems consistent with the behavior you have seen previously.

    • Developer

      GlennM, replied over on your other thread but in short, it's probably that the SD card can't keep up.  Try reducing the logging or replacing the card.

  • Hi Devs! Is it now possible to transfer telemetry data to an graupner HOTT system?
    • There is  a patch for HoTT protocol support by Adam Majerczyk

      I'm using HoTT for two years with APM and with PX.

      Also there are some MAVLink2HoTT translators. I made one of them. It's firmware for Arduino micro etc. You can easily find it within this group.

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