Copter-3.3 released!

After months of testing by the beta-testing team and no significant issue during the soft release, Copter-3.3 has been released.  You can load this version onto your vehicle using the Mission Planner or APPlanner2's Install Firmware screen.

As mentioned previously, 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 (i.e APM2.x) can continue to load Copter-3.2.1 from the MP/AP2.

Support issues should be reported in the APM Forum.  Enhancement requests and confirmed bugs should go into the GitHub issues listThe 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.
  • TradHeli is still in beta testing so it remains on AC3.2.1 for now.

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

Thanks to Marco and all the beta testers who risked their vehicles so we could iron out issues 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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  • Developer


    It's up to you if you'd like to update or not based upon whether the new features interest you.  If you're totally happy with Copter-3.2.1 it's fine to stick with that as well.  At some point you'll find that it's harder to get answers to support questions if you're using Copter-3.2.1 but I don't think that's the situation immediately.

    The short-leg issue on the IRIS is somewhat well known.  The longer legs apparently reduce vibration somehow.

  • do i need to update new frimware 3.3 for my iris+ ? i'm using 3.2.1 fw now, many error with small legs. i must put tall legs then it work ok.

  • Developer

    I made a mistake during the release process yesterday and TradHeli has accidentally been upgraded to Copter-3.3.  The testing for TradHeli isn't complete so we will revert it to Copter-3.2.1 asap.  Any TradHeli users out there reading this should no upgrade to Copter-3.3.

    Multicopter users should not be alarmed, this is a TradHeli specific warning.

  • Very impressed with 3.3!!! No flight problems whatsoever. Every version gets smoother. Thanks to all the devs, 3dr, and Mr Anderson for encouraging this great open source approach!! 

  • Developer

    @James, I removed a personal comment that you made in your post above.  Please be nice.

    Re your issue, if you have a log, that'd be great.  Please post it in the APM:Forum.

  • Upward and onward! :)

  • Thanks @Randy, the log file is here:

    Any help appreciated.

  • This is good to hear.   Are there any plans to implement lidar lite via pwm (on it own seperate to the OF needing to be installed and working) to control the altitude simular to the maxbotix sonar in Alt Hold with 3.2??

  • Developer

    @Gareth, sure.  any chance you could turn on logging-while-disarmed and attempt to do the accel calibration and then stick the logs somewhere (maybe the APM:Forum would be best).  I've had a quick look for your logs but don't see them anywhere.

  • Great news! Thanks a lot for your efforts!

    Came at the right moment as I realized just yesterday, that I need to switch to 3.3 that the SET_POSITION_TARGET_GLOBAL_INT MAVLink-messages from my project FlightZoomer would get processed.

This reply was deleted.