Arducopter 2.0.24b

Hopefully the long road of beta is almost over.

I've done my best to address DCM drift issues. Again, this is not the ability for the quad to hold a perfectly level spot, it's the 20-30° error introduced by vibration and rapid maneuvers. 

We've upped the gain on the DCM to recover faster. There is still room to tune these gains even more aggressively. I'll be looking for input from everyone on this. To edit the gains, go into system.pde.

To optimize the hardware, please be sure to add a windscreen to your barometric sensor and solder the filter pads on your IMU shield. A piece of felt works best. No closed cell foam.

To get the best yaw performance, calibrate your ESCs, and adjust any tilted motors. The copter should NOT yaw when lifting off. If it does it's you, not me! If you want higher performance Yaw, switch from the default to rate based yaw in APM_config.h.

I added two in-field calibrations to the arming and disarming gestures. Hold disarm for ~ 10 seconds to level the copter. Hold arm for ~ 20 seconds to fly in auto-trim mode for about 45 seconds. It will exit auto-trim automatically and fly normally. Don't worry about counting out the time, just wait for the flashing lights to enter either mode.

Alt hold has been re-written and uses a single PID for both Baro and Sonar. Baro has been more heavily filtered so the D term could be brought up. It's essential for smoother alt changes. It also helps that the internal PID integrator is the same value for both now. From 3 to 6 meters, the Baro altitude is mixed with sonar for a smoother transition. The alt hold PID could use more fine tuning, let me know your experience.

This version also now includes Randy's Heli code. 






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  • I just loaded up the soldered the filter pads, and loaded the new code through the planner. Did the usual setup. 

    When i hold arm for more than 10 seconds is there some LED indication to let me know that its in auto-trim mode?


  • Jason!

    Please, include following safety issue in next releases:

    Motors can ONLY be armed if multirotor is in Stabile mode.  Ones I forgot to check it – it was in altitude mode, but today (worst case) – in RTL. Quad just flipped over! And I could not cut motors by disarming.

  • Cool stuff guys,


    Thanks Randy. I am going to whip my APM off the uav and slap it on the old 450 for a tester. will let you know how it goes.


    thanks for the hard work



  • Hello,

    Ive uploaded new firmware - 2 things, during setup how do I have my quad facing? I ask because I can't seem to have heading dead center on 0 (arrow up) and so im confused as how the quad knows which is front to back?? And 1 more thing, disarm (left yaw) will not work, green LED just stays solid, arms perfectly (yaw right).
  • Oh, it was going too well, I suppose.

    Tried the latest code at an indoor event tonight, both the sonar and baro holds worked very well, sonar about to 1.5m AGL, rock steady, baro above that I assume, also very steady. Quad trimmed so nice, it almost held position for minutes at a time.

    And then in slow forward flight, it lost its marbles and flipped over as quick as a flash, breaking the top two rings, two arms, various screws, one prop.

    Not sure what I'm looking at in the log file.

    I'm using a DX 8 with telemetry, and about all I can say is that it wasn't the battery.

    All four motors and speed controllers functions normally, all sensor still operational with the brain out and on the workbench.

    I so hate it when the reason for a crash is unclear.......

  • Wonderful code.  I am having a great time with it.  I have worked hard on vibration reduction and have not had any stability issues.  By soldering the pads I could raise the P from .28 to .32, so this was good suggestion.  I pushed the machine hard in simple mode with a cam and everything stays in control through several batteries.


    Yesterday I upgrade the code and under Altitude test for the Baro, it remains at 0cm.  Sonar tests OK.  Could the Baro get turned off somewhere and I can not see it?

  • LOITER issue with 2.0.24b


    I'm not sure if this this is an issue with the code from the trunk or also it's with the code on the downloads tab...or if it's an issue at all... but I tried the loiter function on 2 separate APMs and it seems like the APM does not respond to throttle. Both quads I tested consistently kept on rising and not holding position(and due to slow reaction on my part I actually lost one of them in the desert :( )  Lowering throttle did not even change the speed of the motors. Is this a code issue? 

  • Behavior of leds.

    Cannot understand if there change in led behavior since 2.023 release, particular in RED lead. Previously red when led was blinking – ACM was searching for satellites to lock, when it is solid (some seconds after blue led on GPS receiver become solid) – ACM is receiving GPS data.

    Now, my read led is not in operation any more. It is just off all the time. Is it ok?

  • Download site showing 2.0.25 while the APM planner upload firmware is still showing 2.0.24?

    Are they in sync?


  • Jason and AC team great job on this code flys very nice i think you hit the sweet sopt really having fun flying this new code Tom
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