Dagar, thanks very much for your inquiry. You guys here are pretty intimidating, but the OpenAero VTOL is a fairly steep learning curve, so I figured if I could still do that one, I'd move up higher in the food chain-- to the top, in fact-- and see if I can wrap my head around the PX4 software.
To oversimplify, Happy Sunday's software sets up eight identical channels in the KK2.1.5 board that begin with pilot input and allow the mixing of any data source in any amount- accelerometers, gyros, The results can be assigned to any of the eight PWM outputs as motors or servos. Once you get it, it's really versatile. In my iteration of this system, I
1)-start with Rx output to the board (can be PWM or PPM), and mix filtered gyro and accelerometer sensor data to the elevators and, ailerons channels to get elevon mixing. Polarity is found by observing the control movement and adjusting accordingly. Autolevel is available, and I use it.
2) I assign throttle input to two motor channels, with vertical axis accelerometer data tweaked in some mysterious PID way to achieve fairly good vertical stability.
Transitions are pretty neat- you set up one batch of input-outfut channels for P1 (hover) and another for P2 (level flight), and blend them from all P1 to all P2 with any combination in between you like. For, for example,P1.3 for slow forward flight. I could say my hover setup is all scaled 50 and all scaled -50 for hover, but it's meaningless till you work with it.
Honestly, Happy Sunday has a great idea. If the board were more capable I'd still be using the system---I've paid my dues in fried neurons- But alas. And the PX4/pixhawk looks like light years ahead, in hardware capability anyway.
As for my prototypes, I am writing this on a connection so slow that a page load can be ten minutes, if it's a picture, and mostly the server boots me before the picture ever gets uploaded. A
ccidentally cut phone line, so my usually very good broadband is stone dead.
I've cut off the laundry rack, and am building two more larger single-axis articulating motor mounts for the first bird. Just too ugly, too draggy with all that junk hanging out in the breeze. I just sent the ply off to the laser cutter today. But the second, smaller bird is ready, and so am I.
Will try to upload a picture again.
Hooray! It worked. The blue one in back is going to be retrofitted with articulating motor mounts- yaw in front and pitch in rear.
Sorry for the long post, but Happy Sunday's software deserves a decent shot at description--it's good.