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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      • I think this was just a rationalization of what the value needs to be.  I've been pushing for it to be 4500 for a long time, which is what I typically run.

  • test flight a while ago, hovered it  3 meters away from me. My quad went to failsafe due to low battery. but instead of landing, it performed RTL instead of LAND. I thought it should choose whether to LAND or RTL based on hardcoded 5m rule? is this normal? Luckily i was able to switch flight modes to cancel RTL else it should have hit the wall.

  • Hello!

    I used version 3.3.1 with coaxial octorotor. I try take off in Stabilize mode. Compass and GPS disable, because next step I want use PX4FLOW. But when I move throttle stick only on one step coaxial octorotor take off very fast and I cann't control it, when I move stick back on one step throttle too small for take off.
    When I use 3.3.1 with quadrortor everything all right with take off.

    Can somebody analyze my log? I will attach the file coaxial octorotor. thanks!

    2015-11-06 09-26-13 95.bin

    2015-11-06 09-26-13 95.bin.log

    • Developer

      I don't see anything in particular wrong.  I'd recommend trying a few things:

      • re-calibrate the ESCs
      • do the motors test to ensure the motor order and direction is correct (check the props too!)
      • if the above doesn't help, try going back to Copter-3.2.1 (it's still available through the MP's previous firmware link) so that we can be sure it's a firmware issue.  If Copter-3.2.1 works but Copter-3.3.1 doesn't then it's likely a firmware issue and we can look into it further.
    • I had a quick look.  Has this vehicle flown before?

      I don't see anything wrong though I'm not the expert in multirotors.  I see your motor outputs are about 1250uS PWM on the first test.  Then the second test they don't go above 1500, I think it flipped over?

      I suspect it might just be that your multirotor is overpowered, or the ESC's aren't calibrated properly?

      • Thanks for looking into Rob! But when I use prevuious version 3.2 with this coaxial octorotor everything all right (I didn't change battery and didn't calibrate ESC's). I change only version APM. With 3.2 I can control multirotor. With 3.3.1 it flipped over.

  • I have two Pixhawk running arducopter with version 3.3.1 and one with
    3.4-dev. The two have a message via NSH Overtime task 19. Is there a problem in flying that way.

  • Wil there be ever oneshot support with pixhawk in the future?

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