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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  • Hi,

    Attached is a log from a crash using 3.3 rc5,

    Couldn't find the reason yet



    2015-07-20 13-13-32 7 crash.bin.log
    • Developer


      Looks like I need permission to download the log file..

      • My bad, Its open for all now.

        Thanks for taking the time.

        • Developer


          I've had a look at the logs and it looks like a failure of the back right motor (#4).  I think it's this because the actual roll and pitch are following the desired reasonably well but then suddenly separate.  The throttle is not very low at this time so there's no reason to suspect it's the THR_MIN issue reported by IvanR.

          3702792886?profile=originalBy the way,. there are other bad things happening in this log which makes me think the vehicle has very high vibrations.  Could you please upgrade to AC3.3-rc7 which includes the new VIBE message, do a short flight and post the dataflash logs here?

          The issues are the DCM vs EKF attitude estimates are off by >10 degrees and there is a portion in the log just before the crash where the vehicle's climb rate is negative but the baro and sonar alt appear to climb.


          • Thank You!!

            I will rebuild it and post the log

        • Looking at the logs it seems that you were on the ground most of the time. Then when you did fly your VCC dropped a LOT as did your volts on your main pack. Your PDOP is all over the place and it looks as if you were moving it around a lot while it was initializing. It's kind of hard to read these logs all in all but all these things adding up looks like a crash was waiting to happen.

  • Hi, i fly 2 weeks on 3.3 RC 7 all is great but the pixhawk overwrite the m8n config and i must wait 10 minutes for hdop under 2,3 with 3.2 i wait at same day 10 minutes earlier 3 minutes for hdop under 1,8.

    Sorry for my bad english.

    3.3 RC 7 is pretty cool only gps is extremly slow.

    I have configure ublox manual over passtrough all is fine 2 minutes for hdop under 2,3.

    When i disconnect the battery for 20 seconds i wait 5 minutes an have hdop over 3

    In u center i see all my config is @ m7n settings this is bad
    • I post a log and photos from my copter when i @ home.

      The gps modul is on a tower than comes the level only with pixhawk than comes gfk under this the battery and power modul than comes gfk and under this is the power distributor. All my flights was outdoor.

      Only after configure with ucenter without battery disconnect i have 12 sats @ cold start in max 2 minutes. After disconnect the battery and reconnect i see in u center under gnns config all unchecked under rates 1hz 1000ms.

      I store the config in bxxx and Epprom
    • Developer

      By the way, in the dataflash log's UBX1 and UBX2 messages there's some additional info including a jamming number (see field "jamInd").  Not sure but these may also provide some additional information when the GPS signal is facing interference from nearby electronics (like FPV equipment).

      • here the log

        over the complete fly no good hdop in complete free area hundrets of meter nothing

        i cant open this file in MP

        is a 500er Frame


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