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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    • Developer


      Sorry for the slow response.  I may have answered your question on the APM:Forum but in case that wasn't you, you can use MOT_THST_MAX to reduce the maximum possible output to the motors.

    • I have a mini apm 250quad v3.2.1 throttle max is there but on my pixhawk v3.3.2 no throttle max on my quad or hex but both fly fine have you calibrated your escs just a thought
      • pretty sure he said he is running DJI opto and DJI motors which means he can't run the endpoint calibrations as the DJI stock firmware doesn't support it.

  • I'm having lots of problems with mavlink telemetry both through bluetooth and minim OSD. minim OSD now almost never works. Resetting the board doesn't help. Repowering very ocasionally works. I think its more likely that these devices simply aren't receiving mav data. Is there anyway to make this more reliable? I'm also going to try going back a couple of revs because it wasn't this bad before. Could still be my hardware, but just seems odd.

    • Its as simple as setting correct SR settings for the correct SR port# and choosing the correct serial port. P.s. also, if you are using a **hawk its a god idea to reflash bootloader. 

      p.p.s. Do not forget to disable flow control for the minimosd serial port.

      • You actually might be right - a bunch of these settings appear to have been changed. I didn't do it so I guess it happened when the firmware got updated. Grrr.

      • Yeah, I've done all that and its been working fine until the last couple of days

  • @Nathaniel Tyson Taking off in GPS modes or Alt Hold has been SOP for quite some time with other flight controllers. It doesn't strike me as the best of ideas but nonetheless for many people it's totally normal and if you have a good GPS signal there's really no reason not to.

    • Oh I see, Seams like an odd thing to do to me, lose sensitivity at a critical phase of flight. But to each there own. Thanks for the response.

      • You don't actually loose responsiveness, it's just a different approach or style to lift off. You raise the throttle up to around 50% and the flight controller ramps up the speed as required to get it to hover height. I think it came from the evil world of DJI. 

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