ArduCopter 3.0.1 has been released and is now available in the Mission Planner,, GitHub and the new Downloads Area.

Warning #1: Compass calibration and reducing interference is far more important than with 2.9.1b

Warning #2: GPS glitches can cause sudden and aggressive position changes while in loiter mode.  You may wish to reduce the Loiter PID P to 0.5 (from 1.0) to reduce aggressiveness (see image below of where this gain can be found in mission planner).

Warning #3: optical flow is not supported but will be back in the next release (AC-3.0.2 or AC-3.1.0).

Warning #4: loiter turns does not maintain altitude.  This bug will be fixed in AC-3.0.2.

Warning #5: This release has only been lightly tested on Traditional Helicopters.

Improvements over 2.9.1b include:

  • Inertial Navigation for Loiter and Auto meaning much more accurate control (Randy,Leonard,JonathanC)
  • 3D navigation controller follows straight lines in all dimensions between waypoints (Leonard,Randy)

         WPNAV_SPEED, WPNAV_SPEED_UP, WPNAV_SPEED_DN, WPNAV_ACCEL allows configuring speeds and acceleration during missions

  • "compassmot" to compensate for interference on compass from the pdb, motors, ESCs and battery.  (Randy,JonathanC) (Set-up video here)
  • Safety improvements:
    • simple Tin Can shaped Geo Fence
    • pre-arm checks to ensure all calibration has been performed before arming (can be disabled by setting ARMING_CHECK to zero).  (video description here)
    • GPS failsafe - switches to LAND if GPS is lost for 5 seconds
    • stability patch improvements to stop rapid climbs in very overpowered or overtuned copters
  • Circle mode improvements including "panorama" when CIRCLE_RADIUS set to zero (Randy,Leonard)
  • SONAR_GAIN parameter added to allow better tuning of sonar surface tracking
  • CH8 auxiliary switch (same features as CH7)
  • works on PX4 (some minor features still not available) (Tridge,PatH)

How to upgrade:

1. Make sure you are using Mission Planner 1.2.59 or newer (get it here)

2. Click on the MissionPlanner's Hardware, Install Firmware screen.  The version numbers should appear as "ArduCopter-3.0.1", then click the appropriate frame icon and it should upgrade as per usual.

3. Reduce the Loiter and Alt Hold PIDs if you have modified them from the defaults.  The modified PID values for the 3DR frame can be seen in the image below.

Note: Nav parameters have been combined with Loiter so do not be concerned if you can't find them.

4. Although not directly related to this release, if you purchased an APM prior to March of 2013, update your PPM encoder to the latest firmware (instructions here).

5. Try out the new version in stabilize mode first, then alt-hold, then loiter and finally RTL and Auto.

Numerous How-To videos are available:

Special Thanks to MarcoDaveC and the large number of testers on the pre-release thread who put their copters at risk during the extended testing period.  Some of their videos can be found hereherehereherehere and here.  Thanks also to MichaelO for the MP changes required for this release.

All feedback welcome.  Please put your questions, comments (good and bad!) below.

Views: 386579

Reply to This

Replies to This Discussion


     If you look on the bottom side of the APM you should see the I2c labels which, from the outside going in are GND, 3.3V, SDA, SCL. 


     It's almost impossible to know without seeing a tlog or dataflash log...


     By the way, did you have any other electrical devices on the copter like an FPV system?  In either case we want to be able to filter out these glitches but in terms of finding the cause of the glitch, we've seen cases where FPV or other sensors can cause them.  Check out this video for one that I found recently (it's not a commonly available sensor).

For APM2.5 it's pin1 3.3V pin 2 SCL, pin3 SCA, pin4 GND (see diag)

For APM2.0 it as randy say pin1 SCL pin 2 SDA pin 3 3.3V pin 4 GND (see below)


     For yaw problems on AC3.0.1 we've normally found they're caused by motor imbalance.  If you turn on the MOTORS message using the Log Bitmask field (can be found in the Advanced Parameters list) we can see how far apart the motors are when you're in a stable hover.  If it's over 200 you can definitely have problems with yaw.

NOte: the image above shows enabling the IMU but you can see "Default+Motors" is right below it.


     Sorry for taking so long to look at your log.  So here's a graph of altitude (top), desired vs actual roll and pitch (middle) and climb rate (bottom) and as you described it's pretty clear that the copter is getting wobbly as it's descending.

     Looks like it's maintaining the desired descent speed of 2.5m/s (WPNAV_SPEED_DN parameter) which is a bit fast.  I believe the default is 1.5m/s.  I think copter's just get wobbly when you try to come straight down that fast.  If it's coming down on an angle then it can manage that speed ok but straight down it runs into it's own prop wash.

     The roll, pitch rate parameters look reasonable (just a touch higher than defaults).  I'm skeptical that you will be able to tune out the wobble.

I was wondering how you were able to fix your ESC issue?  I just ordered the same ESC's from RCtimer after the fact of reading some of your problems. I was planning on using these in my X800 which I ordered from RCtimer as well, and now I'm starting to have regrets. Thanks for any information you can provide.

thanks i have 2.5 . i wont to decrease actual 80% compassmot

tought this version 3.01 work very well in all flight mode(really great software job). i try alt hold loiter auto guided and follow me , but not set fail safe and fence.

HI Randy,

Not a problem as I realize how busy you must be. Your timing is perfect as I am planning to look at this later today. I will re-tune the quad from the beginning because of the new, stiffer, carbon props and decrease the descent rate. Yes, I remember changing the default a while ago with the older flexible plastic props.

Best regards,




    Sorry, I misread your post.  I thought your AC version was 2.5.  If you're just upgrading from 2.9.1b to 3.0.1 it's not so bad.  In the main part of this discussion above you'll see a screen shot of the few parameters that have changed.


         That is right. Sorry for my English level. So, If my Quad can flying good on 2.9.1b, NormalIy I can use same PIDs except those changed parameters in 3.0.1?

Please configure and test the safety systems before trying the fancy features.  I suggest setting up the fence and the failsafe before auto guided and follow me.  

Reply to Discussion


© 2020   Created by Chris Anderson.   Powered by

Badges  |  Report an Issue  |  Terms of Service