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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      • Cool feature, good to know.

      • The Lost copter alarm works really well. Tested is a couple of days ago and it's nice to be able to let it beeb once or continue to beep as long as the stick is held down / right

        1:10 in the video

  • Has anyone else tried to use serial 4/5 with storm32? I have got it working only in tele2 port. How ports and configurations match? Are ser1-4 configurations tele1,tele2,gps,ser45? 

    • Hi VP Kuisma, and all

      I'd did it, and same as you.

      That i can see by trying the Copter 3.3rc4,serial 4: 57k protocol 1,(full parameter tree)

      it's that with the Storm32V0.76x, i have in TM MP two quad, on one the right place and one 0°N, 0°W!?

      and when the teensy or Tower had the mavlink flow, mode change continuously from stab to rtl (or unknow for Tower) but not by TM and MP?!

      Maybe due to the new bridge for th Strom32 by the MP telemetry, or something like that...

      i'm waiting for the Betacopter V3.3Rc4 by OlliW, wait and see...

    • I read that still only telem 2 is possible with storm32.

      But I have a similar question: I want to switch OSD and teensy (S-Port) to serial4. But what are the corresponding SR parameters for Serial4? SR3?. Its a litle bit confusing.

      Cheers Gregor

      • Developer


        I'll make a wiki page to describe how to assign the serial ports but basically it involves modifying the SERIALX_PROTOCOL parameters where X is a number from 1 ~4 so no need to modify the SRX_ parameters I think.

  • Hi, I'm currently trying to get 3.3b working on PX4+IO.

    Currently I've gathered a couple of questions:

    1. How can I understand that my i2c ESCs are even detected in system? It's mkbl esc v1.1.
    2. How can I verify, that my PX4FLOW module is up and running? Do I need to build additional modules to get it working?
    3. As soon as 3.3 dropped support for APM boards, maybe it is possible to bring back console? I think in case of PX4/Pixhawk lack of resources is not that awful.
    4. Could not ARM my PX4 board. Neither with "rudder right", nor with "Press PX4IO safety button, wait till it gets solid, rudder right". It just won't arm. No preflight alarms generated.
    5. Is there a place where I can get "up to date" meanings of LED lights and Buzzer sounds, besides "in code"? Sometimes I feel like shaman trying to figure out what's going on.

    /!\ IMPORTANT /!\ Dear devs who are in contact with Pixhawk webmasters, please add note here ( that TO FLASH PX4IO YOU HAVE TO UNPLUG PX4FLOW!!!11oneone. I upgraded PX4IO many times and still sometimes you just follow the instruction which sometimes results misunderstandings.

    Thanks in advance.

    • Ok. digging process on MK-BL ESCs goes on.

      For now there is new information: 

      1. To enable autorun of mkblctrl driver on arduCopter you have to create file /etc/APM/mkblctrl with correct motor numbering.

      Does anybody know what "correct motor numbering" means in terms of syntax or usage example?

      2. Found this config here. It moves me one tiny step forward on understanding how does it work inside.

      • I guess I need dev's help after all. I found 'mkblctrl' in code here and I found mkblctrl driver, but I can't really figure out at which moment driver loads config from file and what options are needed. 

    • Developer


      1. I've heard of some developers experimenting with the I2C ESCs but I've never used them and I don't think they're supported in ardupilot.  They are supported in the px4 stack which means we could enable the pass through but I've never done that.  The plan is more to move to UAVCAN bus ESCs rather than I2C ESCs in case that matters.

      2. PX4Flow wiki instructions are here.  I see in the MP's status screen there are some new "opt_m_x", "opt_x" values that have appeared.  I'll bet those update when the sensor is working.

      3. It's possible to bring back the CLI but it's a clunky interface and we're trying to make everything done through the ground stations with MAVLink if possible.  Any particular features you're missing?

      4. It's probably the RC is not calibrated properly.  If you set the LOG_BITMASK to All+Disarmed it'll log while disarmed and we can see if the RC is working correctly.  The MP (and other GCSs) also allow arming so you could try pushing one of their arming buttons and watch for the failure message on the HUD.

      5. pixhawk leds and sounds are on the wiki.  We're making progress on updating the wiki ahead of AC3.3 but it's not completely up to date yet - the leds and sounds have not been updated yet although most haven't changed.

      There shouldn't be any need to update the PX4 IO board separately anymore.  That's done automatically when the main FMU flight code is uploaded.  Sorry, we need to zap that last bit on that page.

      Thanks, hope this helps some.

This reply was deleted.


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