ArduCopter 3.2 ready for wider use

After months of testing, ArduCopter 3.2 (aka APM:Copter) is ready for widespread use and we invite all users to give it a try.  In order to manage the support load at first it will be available only through the Mission Planner and APM Planner2's Beta Firmwares link.  This link is visible from the regular "Install Firmware" page if you check the "Advanced View" on the Config/Tuning >> Planner page.  On APM Planner2 the "Advanced View" it is under the File menu.

In about two weeks we plan to replace AC3.1.5 with AC3.2 as the default version dispensed by the ground stations.

The full list of changes can be found in the ReleaseNotes but here are the highlights:
Flight Mode Enhancements:

  • PosHold flight mode: similar to Loiter but with direct response to pilot input during repositioning
  • ACRO mode handling improvement EXPO (for faster rotations)
  • Drift mode uses "throttle assist" (similar to AltHold)
  • Smoother transitions between flight modes (i..e when entering Loiter or RTL from high speeds)

Mission Enhancements/Fixes:

New Sensors/Devices:

Safety Features:

  • EKF/DCM check will switch to LAND mode if heading error > 60deg for 1 second
  • Baro glitch detection
  • Pre-arm check for Gyro calibration success
  • Pre-arm check that internal & external sensors (gyros, accels and compass) are consistent (Pixhawk only)
  • Parachute support (Pixhawk only)
  • Feedback to Pilot when taking off in AltHold, Loiter, PosHold (i.e. motors spin up a little as throttle is raised)
  • EKF (new attitude and position estimate system only used for reference in this release)

Bug Fixes:

  • Pixhawk GPS driver buffer overflow that could lead to missed GPS messages
  • Pixhawk I2C bug that could lead freeze up if I2C bus is noisy

Known issues/Warnings:

  • Pixhawk users will need to recalibrate their compasses
  • PosHold won't show up as option on FlightMode screen if you have an old version of mission planner.  Please select Help > Check for Updates
  • Landing detector is more strict meaning it may take longer to disarm after RTL, AUTO
  • Set THR_MID parameter especially if you have a very powerful copter because "Feedback to Pilot" raises throttle to 1/2 of THR_MID
  • Spline twitches slightly as it passes a waypoint especially if WPNAV_SPEED is set > 500.
  • Dropped support for NMEA and SIRF GPS on APM boards (ran out of Flash space)
  • Dropped ssupport for sonar for MultiCopters on APM1 and TradHeli on APM1 & APM2 (ran out of Flash space)

If you hit issues, please post them in the APM Forum and include a dataflash log file if possible.

Special thanks the Marco and the Beta Testing team from the AC3.2 beta testing thread who put their copters at risk in the pursuit of a smooth, safe release.  Here are links to some of their videos: Marco's DJIs900, Holger's Water Tower, Josh's Acro, Ray's TradHeli2&FPV, Raph's Hawaii, PhillS's CommandYawThor's Zombie Run&FollowMePhanivyas's Test, Rob's TradHeli, Christian's Test1&Test2Balloon's Spline, JimJ's FPV, Ultrojo's ROI & Spline&FollowMe1&FollowMe2, Troy's Mission

Thanks also to the code contributors to this release including Tridge, Jonathan, Leonard, RobL, Paul Riseborough, MichaelO, Julien Dubois, David Dewey, Andrew Chapman, Emile, Allyson and many more.  If you want to get involved check-out our dev wiki.

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  • Whoops, I forgot about soldering the jumper to select 3.3v.

    As for soldering on the extra GND wire I think it's unnecessary.

    The GPS port on this chip has connections for Tx, Rx, + and GND, the + and GND will be being sent to the hmc5983 chip through the circuit board (how else would the 5983 be being powered?) and the processed signal, with that GND reference, is sent out through the SDA+SCL lines to the APM.

    I've also had a ublox 6m compass/gps module that was wired up the same way on another installation. Same as this -

  • MR60


    Here is how I bridged the GND from the GPS port to the missing Compass ground port:

    3701879690?profile=originalAnd then you have to hack a cable to be able to plug it in a pixhawk GPS & compass DF13 connectors:

    3701879781?profile=original(the white connector and cable is orignally purchased at Drotek's site; only four wires of the GPS port are connected on the six pins DF13 connector of pixhawk : tx, rx, 5V, Gnd).

    For the compass the M8 has only the two SDA/SCL lines, but I added ground for safety and good practice : never measure a signal without its associated ground reference. We have seen funny things on pixhawk when the ESCs were connected only with their signal lines , without ground. So better take precautions ....)

  • How about setting the 3v or 5v jumper? see photo .. I thought you also had to set the baud rate and the std 1kz update rate to 10kz.. 3701879348?profile=original

  • I just plugged my Drotek M8 in using some spare cables I had.

    Didn't have to reconfigure anything, just plugged it in to my APM, did the compass calibration and compass mot and that was it. It has performed perfectly ever since with no deviations and always showing the right heading when compared to a normal compass.

  • Hi Hugues..  I use the M8 from Drotek , is it necessary to change the config using Ucenter ? and can you tell me more info on the ground pin issue and what does it affect ? Other wise it seems to work well I have 20 sats and a HDop of 1.2.

    Regards Reuben

  • MR60

    Comment by 勇進 湯 yesterday

    Can  M8N GPS work for APM 2.6? 

    Yes but beware of two main issues with the Drotek model (probably explains its relatively low price, 50% cheaper than the M8 from virtualRobotix):

    -the compass port does not have a ground pin! I did solder a ground bridge on mine.

    -the ports are not df13 connectors. They are impossible to find micro molex connectors. You are forced to buy the cables at Drotek and these connectors are so tiny they are unfit for diy cable hacking.

    Also their cables are horribly stiff so transmit vibrations...

  • @jim they ARE getting underpowered flights and simply NOT noticing because of being new pilots..

    the experienced quad/multi   rc pilots  did  not go for the IRIS or IRIS+.. was a bit too pricey for an experienced RC pilot it was mostly folk like moi I suspect ..

    fixed wing UAS(paparazzi) dev or newbie buying the IRIS/IRIS+ to get a quick start on HW so would only have to worry about flying/coding while still having a UAS one could freely get into the guts of without reverse engineering(phantom 1 and 2 etc) ie an OpenSource based  product.

    xcoptercalc models reveal the whole picture on power vs weight vs prop vs kV at christians site.



  • @hotelzululima -- thanks for the reminder. I have the phantom nuts and spare propellers so I will give this a try. But I am surprised that others aren't reporting under-powered IRIS+ flights in their logs. Is the high throttle considered normal with the phantom-style propellers and people are just not looking at their logs?

  • @jim please check out christians pages at about using the original 1047 props on the IRIS+ with 6mm phantom nuts  almost same flight times on 3S 5400 lipo but puts the throttle back down to 54% with gimbal..


  • Tested out my hex on the latest release and didn't have any flight issues.  Used droidplanner for the ground station and used all 6 follow me modes.  All worked well.  Only issue was with the gimbal not pointing the camera down or up as the alt and distance changed.  When in follow mode I lose control of the gimbal tilt from my rotary switch on the transmitter which I should, and gain it back when follow is turned off.  

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