Latest AC2 update

This is to let you know that AC2 beta has been updated based on everyone's feedback. I think we're getting closer to a full release.

Things to concentrate on:

Logging - Logs are the most helpful thing you can post. If you have an issue, please post the log and let me know where to look.

Altitude hold: The Dterm was a bit too aggressive preventing the copter from changing altitudes. It's been lowered by default to 0.03. If you have trouble changing alt, try adjusting this value down a bit.

Mission scripting was a bit broken - fixed now.

Frames have now moved out of the CLI and into defines. This means you'll use the download tool to grab the frame config you need from the start. This makes the code a lot simpler internally and saves a lot of code space.

There is a newer rate based navigation algorithm (above in Flash) to try it, set this parameter in APM_Config.h and upload with Arduino:

#define NAV_TEST 1 // 0 = traditional, 1 = rate controlled

The sim above in Flash now addresses the steady state error with the I-term. PID's are great ;)

It's set to hold 4.5 M/S right now. It may not beat the wind yet, it's still limited to Pitch Max of 18° That will change for the release to full 45° pitch. This will let the copter fight high winds in WP mode.

Lot's of other minor tweaks to improve performance.

Please post all issue to the issues list:



E-mail me when people leave their comments –

You need to be a member of diydrones to add comments!

Join diydrones


  • Ok, that was the mistake. Thank you Chris for the good advice.
  • Thank you Chris for the fast answer.

    Now I'm on work and can't check where I have plugged my GPS module. But I have checked my latest photos (two weeks old) and at these photos the GPS module is plugged to the connector on the APM board.

    But I will have a look today in the evening when I'm back at home.

  • 3D Robotics
    Schwabenkart: that probably means that you've got the GPS plugged into the wrong port (the one that says "NO GPS!").
  • Last weekend I worked on the configuration of my AC. I used the code.

    Because I want to use the camera stabilization feature I enabled that in the ArduCopter.h, compiled and uploaded the code with the arduino IDE.

    I think I found a bug ? Or perhaps I havent done all the neccesary configurations in the header file ?

    The APM won't go to the end of the boot sequence with the GPS connected so that I can't arm the motors. Only if I disconnect the GPS the boot sequence will be finished.

  • Ah, "P" for plus. Got it, thanks!
  • Developer

    Yes, spec your frame in AP_Config.h


    QUADP_FRAME = the quad +Plus configuration.

    QUADX_FRAME = the quad X configuration.


  • Sorry for the dumb question, but if we're uploading via arduino do we set the frame in APM_config.h?

    Also, just to be clear, is QUADP_FRAME the define for + orientation?

  • 3D Robotics
    It's now in the downloads section as "ArduCopter 2 Beta 3". Also, if you're loading the firmware via the Mission Planner, make sure you're using the latest Mission Planner.
This reply was deleted.