Copter-3.3 ready for wider use

After months of testing by the beta-testing team, Copter-3.3 is ready for wider use.  Similar to the Copter-3.2 release this is a "soft launch" meaning that for the next couple of weeks, we are asking users to load the new version using the Mission Planner's "Beta firmwares" link on the Install page.  The MP will pop-up a "use at your own risk" message but rest assured, this firmware has been very thoroughly tested.

We also recommend that you use the Beta Mission planner until Copter-3.3 becomes the default (in about 2 weeks).  Open the Mission Planner and select Config/Tuning >> Planner and click the Beta Firmware checkbox.  Then Help >> "Check for Beta Updates".  The download and install will take a few minutes.

Unfortunately this version and all future versions of Copter only work with fast CPU boards like the 3DR Pixhawk (and compatible) boards, VRBrain, NAVIO+, etc.  Slower CPU boards will continue to be able to load the Copter-3.2.1 release.

Issues should be reported in the APM Forum.
The wiki has been mostly updated but if you spot missing items please report them to the wiki issues list.

The full set of changes can be seen in the Release Notes but the highlights are below.

Known Issues/Warnings:

  • users will need to re-calibrate their accelerometers because of 5c (accelerometer range increase).
  • FrSky telemetry users must set SERIAL2_PROTOCOL to "3" and reboot the board to enable FrSky telemetry like in previous versions
  • this version corrects a long standing issue in the HDOP reporting so values will appear about 40% lower than previously but this does not actually mean the GPS position is better than before.

Changes vs Copter-3.2.1
1) EKF replaces DCM/InertialNav for attitude and position estimation which provides more feedback and robustness in case of sensors failures
2) Control improvements:
   a) battery voltage compensation should maintain control as voltage drops
   b) current limiting can be used to reduce the maximum current requested to reduce strain on battery and ESCs
   c) air pressure compensation should reduce need for re-tuning when flying at different altitudes
   d) improved throttle curve should reduce wobbles during descents
3) AutoTune for yaw
4) Cameras & Gimbal improvements:
  a) SToRM32 gimbal support
  b) do-mount-control mission command allows controlling absolute camera mount angle during missions
5) Vibration resistance:
  a) real-time reporting of vibration levels by clicking on Vibe field on HUD (also recorded to logs)
  b) noise weighted average of accelerometers used to weight IMU towards the one exposed to less vibration
  c) accelerometer range increased from 8G to 16G to allow use in higher vibration environments (i.e. reduced "clipping")
6) Other:
  a) improved landing on slopes
  b) retractable landing gear support
  c) channels 9 ~ 12 can be used as auxiliary switches (like ch7, 8)
  d) PX4flow (optical flow) support in Loiter
  e) Brake flight mode (stops vehicle quickly but requires GPS)
  f) allow GPS, Telemetry, SToRM32 gimbal to be connected to any telemetry/serial port
  g) Lidar-Lite V2 support
  h) bug fix to RCMAP - remapped channel's MIN, MAX were taken from incorrect parameters meaning all channel ranges had to be the same
7) Tricopter tail servo parameters (MOT_YAW_SV_MIN, MAX, TRIM, REV)
8) Safety items:
  a) crash check triggers with 30deg lean angle error (for 2 sec) even if pilot's throttle is non-zero
  b) modified pre-arm checks to ensure good quality GPS and compas data
  c) lost copter alarm (hold both sticks down and right)
  d) motor interlock & emergency motor stop features on auxiliary switches (ch7 ~ ch12)
  e) RTL_CLIMB_MIN parameter allows forcing vehicle to always climb a few meters at beginning of RTL
  f) LED flashes green quickly if disarmed with 3D lock and SBAS

Special thanks to Marco and all the beta testers who put their vehicles at risk so we could iron out the problems during the testing phase and ensure a more reliable firmware for the wider community.  Here are some of their videos:

ChrisN #1, #2, Paul Atkin #1, #2, #3, Gervais #1, #2, #3, Gleb Falaleev #1, #2, Pomaroli, Michael, Robert Baumgartner, De Le, Robert Baumgartner, Robert Navoni, Maciej Karpinski

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  • T3

    Great work, thank you very much!

    Is auto-land with the PX4flow more reliable than doing it on pure GPS+baro?  How about Lidar-Lite?

  • Anyone else think the motor interlock and emergency stop will the cause of many many crashes?  I realize it would be 100% user error.  However this really seems like we're just asking for it.  I can see it being useful for testing and such.  But in flight, wow.  The same reason we never use low voltage cutoffs on the ESCs.

  • Great to finally get this one out.

    Just a note about TradHelis.  We have split the release process, and TradHeli will not be going stable at the same time.  I will be taking a bit of extra time to get some extra features added for 3.3 TradHeli.  It should not be long, maybe 2-3 weeks.  In the meantime, I should have a new 3.3-RC13 for TradHelis out for testing soon.

  • Congratulations! This has been a long time coming, but due to careful testing and a LOT of community feedback. Thanks to the developers and the testers for all the long hours!

  • congratulations! Great work of a great dev team! I have used all the 3.3 RC versions from 8 up and it flies really great!

  • I think the 'synchronized flying' is a bit of a red herring.

    The real story here is the awesome new features and improved safety and stability with this release, it's flying better than ever.  Great work devs.

  • @randy ,I would like to ask these two aircraft is how to achieve synchronization, if I want to achieve the formation flight in the video, How to follow?

  • @randy I think "synchronized" is a bit of a misnomer with respect to what appears to be happening in the featured video of this post. It looks like these are two pre-programmed aircraft relying on their internal clocks for synchronization. It looks like the programs are initiated at the same time to mimic synchronization from the loiter start point. Can someone shed some light on the true dynamics of the flight? Is one aircraft following the path of the other? Are the aircraft aware of each other? I think those are important details to expose to understand what "synchronized" means with respect to the feature being presented.

  • Developer

    @Jaeyoung Lim, I've done something a bit similar here.

  • Synchronized mission for formation flying is great!

    Is it possible to get any information or tutorials to follow?

    I am having a hard time trying to get documentation about how it is done!

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