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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    • auto analysis has to be fixed in mission planner. It's something Mr Osborne and whoever else is working with him needs to address, but I'm sure, just like with Kev's Log Analyzer, with things being such a moving target right now we are going to have to wait until the final hits and then they can catch up :)

      • Craig,

        Thanks for the reply about the AA.

        How about logging settings?

  • I tested AC 3.3 RC10. This is a very stable release.
    And I wanted to draw attention to the following:
    1. Upload the firmware to Pixhawk AC 3.3 RC10 will be better if the first from AC 3.3 RC 9 down to AC 3.2.1, and then up to the AC 3.3 RC10
    2. Then need to check all the major parameters.
     And they are need to be rewritten.
    2. I do not use the automatic tuning. Better to use the manual settings for test flights.
    3. Very important buttons 'Calibrate Level" It is advisable to use prior to each flight.
    4. I'd like to ask to make the possibility of setting on or off the Audio Indications in auto mode. I can set the switch, but it is better to do it programmatically.
    My first the test here:

    Stabilize mode :

    Auto mode :

    • 1. Upload the firmware to Pixhawk AC 3.3 RC10 will be better if the first from AC 3.3 RC 9 down to AC 3.2.1, and then up to the AC 3.3 RC10

      As one fellow reminded me lately, this will do the reset as well:

      If I manually go in and change the SYSID_SW_MREV from 120 to 0, push the write params button and then disconnect/reconnect the parameters are restored to their defaults

      Saves some time;-)

      • Thanks, I'll try it.

      • Why not just hit the Default button in Mission Planner?  The one on the advanced Param or tree view page.

        I thought this also put all values to default.

        On point 3. Calibrate Level  I founbd it best to do this once, when I can be sure to make the frame level.  Then NOT to redo the calibration unless thge Pixhawk has moved in relation to the frame.

        On another frotn, with the EKF parameters which is the best to adjust the weighting of the GPS to IMU?  I have tried adjusting the Noise BIAS params and this seems to work.  Is this the best place to do this?

        I can see that they are already weighted towards the accels so is it better to increace this wieghting or change the GPS glitch params so that the GPS readings have to be tighter?

        Overall I have found the latest relaease to be very solid and I am just wanting to fine tune a bit.  Thanks for all of the fantastic work.

        • Sorry about all of the typo's and bad spelling!!  It seems that I must have had a few moments of dyslexia. 

        • Developer

          Yes, I agree with Alex and Gervais and created a little wiki page with the three possible methods.

          Thanks for consolidating the info so writing the page was easy.

  • Sorry if this is repetitive (artifact of using a single thread for all feedback regarding this release vs. something threaded like APM 3.3 Forum I wish we could migrate to):

    I have found mixed reports of being able to connect the RSSI port on a FrSky receiver such as X8R to the sbus port on a Pixhawk, then setting RSSI_PIN to 103 to get RSSI input. However, other reports suggest this must be connected elsewhere in order for it to work with OSD, and yet others suggest PWM RSSI input has been implemented but will only be merged "in a future release". Is 3.3 that future release? I tried it and got odd values in the 90% range seemingly regardless of where I put the radio, and even if the radio was off, so I suspect either it is not implemented.

    I have seen reports of others doing this without a filter to convert the PWM to analog, however, so I thought I would ask. Can RSSI out on FrSky receiver report PWM RSSI to Pixhawk, and can it be viewable both in Mission Planner and OSD? Thanks all.

    • I'm using it with  the  RSSI filter as per wiki. 

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