Discussions

I am a junior in Engineering with an intrest in UAVs and 3D printing. Decided to do a multicopter project and have been sitting on/refining a design for about a year now. The design is basically a mix of the V tail quad with the Skycrane with interchangeable functional payloads. I will have the time (weekends) and resources to build it this summer so I am deciding to bite the bullet. When working with this design it became apparent that my choice of boards came down to a few factors.

-Does it have a pre-existing Y4 or V-tail quad config

-Does it come with simple support for Laptop Ground station controlled fpv with Joystick (personal prefference) 

-Does it have decent documentation

-Is the code more legible than makerbot firmware, (built my own 3d printer and have read their firmware so I use Makerbot's painful example as a measure for if code is understandable and easy to tweak)

-Autonomous capability

-Ability to add in more features later

Having 4 of the 5 selection criteria as well as a spot on Flite Test which demonstrated the APM was simple to use there was little competition, so the APM 2.5 was selected. Congrats, you guys have an awesome platform. 

I was browsing the forums and found where someone was working on a V tail quad config:

http://diydrones.com/forum/topics/is-their-a-y4-or-vtail-firmware-available?id=705844%3ATopic%3A1047354&page=2#comments

They ended up abandoning using the APM in favor of the multiwii but I would like to pick up where they left off. I was looking into making custom motor configs for APM and was wondering about the functions of AP_motors_raw and add_motor_raw()

 Josh Potter posted a suggested line of code using add_motor_raw() based on the geometries and I was wondering if someone could go in depth on what the different placement of parameters in this function correspond to.

add_motor_raw(AP_MOTORS_MOT_1,  -0.5,  0.7, AP_MOTORS_MATRIX_MOTOR_CCW,  AP_MOTORS_MOT_2, 1);

The type of answer I am looking for is along the lines of if I have function F of x, y, and z or F(x,y,z) then with respect to add_motor_raw() what are my x y and z. If I have that then I should be able to write a matlab script to generate that code for me or do it by hand. 

I am sorry I can't give more details about the project I am working on but I am planning to post a complete design and build log for the community as well as any parts I design and use for this project to be posted to thingiverse.com to be added to the growing collection of 3D printed UAVs.