APM2 stabilizing a bi-copter

Hi all

I have had a look over the pages at the APM2 and have seen the various setups you can select for it but what I was wondering although it is not listed would it be able to somehow stabilize a bi-copter or will there be a software release soon that will be able to cope with this....

If not I may have to look at modifying my bi-copter to a tri-copter.....


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

Join diydrones

Email me when people reply –


  • Hi Robert,

    I made some mods to the code. Please look at it.

    In Dropbox you will find a new video with the last test.

    The next step is to add yaw mixing to ch3 and ch4 (the servos).

    Please help me out with this. 



  • To be honest... I am noob with Git. Downloading with Git I got a standard version 2.7.3. without the modifications found with the first link you sent. I succeded by copy-paste. I had no errors compiling.

  • Hi Robert.

    I try to share a short video with the first test by Dropbox. Please check your mail.

    The two servos must be centered after power up. They are not centered evan after motor arming.


  • Francisc, please see what I've done in my personal clone here:


    I started with the helicopter code and worked backwards, it seemed easier for me.  Have a look.

    If you want to try this, remove the a gear or whatever you need to do from the motors to make sure it won't spin the "blades", as it's entirely possible they will start spinning immediately.  Also, disconnect your servo linkage so that we don't break anything.

    This is just a first stab in the dark.  I worked until I had a headache and this is as far as I got.

    Let me know what you see.

    Be safe, make sure you won't break your machine or hurt yourself.

  • Ok guys, I'm interested in working on this.  When I say "working with a developer" what I mean is that it has to be a two way street.  There has to be a lot of back and forth with info, because if I don't have hardware to test myself, it's obviously hard to get it right.  I also need you to be able to compile and upload code yourself.  Francisc, it sounds like you're already capable.

    The first thing I need is much more detail on the mechanics so that I can understand what I'm doing.  I went to your Facebook page but I can't see anything.

    Ryan, is this a standard bicopter?  How is the stability?  I've seen those before, but they seem to pendulum pretty bad in the pitch direction?

  • So I haven't heard anybody working on that, but it shouldn't be terribly difficult to do.  If you were willing to work with a developer, it could be done.

    What are you flying this with currently?

  • When you say Bicopter... what exactly do you mean?  There are several different aircraft types that could mean.

    Tandem fixed pitch, tilting nacelles.

    Coaxial fixed pitch with vanes.

    Tandem rotor heli...

This reply was deleted.