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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    • MR60

      The difference you see is due to the smaller props on 4S: they turn faster and thus the frequency is different (higher) than on your3S setup. This shows your anti vibration mount does not blocked lower frequencies as well as higher frequencies.

      • Thanks for your reply and explanation. I have the controller mounted using only a double layer of 1cm squares of 3M 4010 double-sided gel tape at each corner.. After a couple years of 3S, I'm really enjoying this new found world of 4S capabilities.

  • Developers -- My hat is off to all of you (or it would be if I wore a hat).You folks seem to be working 24/7 on the development/testing/analysis/fixes and forum.  I don't know if this is how you make your living or just a labor of love but whatever it is, you are doing a great job of it.  I, for one, really appreciate what you are doing.  A big "thank you" to all.

    • it is an amazing product, it is true, and truly unbelievable effort.

    • Couldn't agree more.

      You dev guys are great!

    • I think we all agree they are the backbone of this project and much appreciation to all of the Devs and contributors!

    • Yes, 100% ACK from my side.

  • It happened again today - in a simple mode, position hold, all control directions were mutating making impossible to control the vehicle, I had to drop if down, thankfully, not from very high. 3.3 rc7 on a tarot 690s hex.

    it flies pretty much great most of the time, so, not sure what this glitch is, it is not common, but it has happened before.

    I could not reproduce it later, in the same spot and same flight path. if it has any practical relevance for review - here is a link to log, it is shortly before min6 mark.

    I will try to dig deeper into that. I flew aramttan in a same spot on my front lawn where I fly test tarot now, as I stopped tinkering on armattan for quite a while, but wanted to test a new battery. what is odd- it got same gps units, same controller, same number of satellites it gets, all seems same good, but, it does wander around much, much less than tarot in position hold. it is quite odd.

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    • Developer


      You've used simple mode in AC3.2.1 and read the wiki instructions here right?  I'm pretty sure you understand simple mode but I'd like to try and rule out operator error.

      So it looks like you've got ch10 setup to turn simple mode on/off.  So when it's off the pilot's controls should all be in relation to the vehicle's actual heading.  When ch10 is on, the controls will all be in relation to the vehicle's heading at the time it was last armed.

      It looks like the vehicle was armed pointing almost directly north.  After take-off the vehicle was pointed east, then pointed south, the back to the east again.  It was facing east when simple mode was turned on using ch10 so the controls would have switched to be off by about 90degrees.  About 10seconds later RTL was initiated followed by an emergency stop.

      While disarmed, ch10 was turned off again so when the vehicle next took off, simple mode was off.

      Does this sound like the sequence of events?

      • I will try to reproduce it again. if logs do not show it, may be it was my own mental glitch, it is possible.

        When I engage simple mode I always do small control inputs first to make sure I can control it and it goes where I expect it, in this case it was the same. then it just stopped going in the anticipated direction and I could not figure out how controls shifted, but, if logs do not show any errors, only way is to make sure again of what happened. I start from my driveway quite often, so, I will try again.

        an operator error here could be if I actually moved myself, or turned 90 degrees after staying facing same direction when drone took off. it is probably possible, as I think of it now. unlikely, but possible. I will try again.

This reply was deleted.


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