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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        • Also cheap USB cables can transfer EMF

  • re throttle stick mid position,  sprung vs un-sprung?

    I wonder what the general consensus is for what people now use and prefer for the throttle stick and whether to have it spring loaded so that it sits in the middle (hover position) compared to having it un-sprung as we used in the past. 

    I can see the advantage for the sprung version that it helps to keep a good stable hover at altitude where you can see it clearly.

    I already have this of course on my DJIs. So I want to try it out on my Pixhawk and APM2 rigs, but would be interested first in people option, experiences and of the pros and cons of this?

  • I'm installed the Lidar Lite v2 on my cuad following instructions, I check in mission planner and sonarrange value is working but when flying, I hope, the copter still use the baro readings, I try to change some params but not luck and couldn't find the issue, or any mistake with params I did, or something with connections, the second log, a windy day, appears an ERR 0-249 , I couldn't find what means in instructions. In third log sonar alt appears but didn't work too. Someone can help me?



    • This from 52 log, looks horrible


  • hi randy, i don't see any amp copter 3.4 in mp and apm 2 ? i have install update mp and apm2.

  • Parachutes not responding as usual in previous versions.  Posted this in another forum (wrong one).  Setting up dual chutes are a large unit, but ran into some odd behavior during testing.  Set the min alt to 0 and tried manual deployment in stab, alt and loiter modes with all working perfect.  But auto deployment is a roll of the dice.  Same thing in all three flight modes.  Tip the unit over and either it will say "detected crash" or "parachutes deployed".  Both kill the motors which is good, but "crash detected" doesn't release the parachutes which would be really bad lol!  Strange.

    • Curious if you are testing the auto deploy while flying or on the ground? Looking through the code, it appears the parachute won't deploy if the telem reports landed=true, in the c++ source "if (ap.land_complete)",

      It also records the barometer readings, and skips the deployment if the readings increase. I see a todo note in the code to check if its actually falling.

      I wonder if the barometer check is the source of your issue. Watching the barometer on several of my pixhawks, the readings fluctuate. Maybe "random noise" from the barometer is affecting the performance?

      • Testing on the ground, so good point about the barometer.  

  • I'm installing A Lightware SF30/B Sonar on my Pixhawk, will APM work OK ?

  • I'm not getting any Bata versions showing up on the MP after clicking "Beta firmwares" .

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