We've got the physical ArduPilot
boards now, and the above is one with the components mounted. As you can see, it's pretty small! We've got channels 3 and 4 (throttle and rudder--that's the ESC and servo in the pic) from the RC receiver (at left) going through the autopilot. It can handle two more channels, but we're not using them right now. When the autopilot is in control, it will steer with the rudder and maintain altitude with the throttle. Elevator and ailerons are under the control of the FMA CoPilot for stabilization.
Channel 5 is used to turn the autopilot on and off and goes into the on-board hardware multiplexer/failsafe
that Jordi designed and we've incorporated into this board. Finally, that's the GPS (EM406) in the top left corner.
This board is just for testing, and I can already see a few small tweaks to make in the next board (we'll switch to a different GPS connector, for instance). I'm still working on the code, meanwhile, but I can already tell you that it will be much simpler (and better) than the Basic Stamp code, thanks the superior hardware of the Arduino. Speaking of which, this project got a nice call-out
from the official Arduino blog!