This controller is inspired by Hugo Peeters' work on instructables

I have taken a modular take on his controller. Dividing it up into logical units that can be interchanged. My default setup consists of 6 modules in a 3x2 configuration. 1 base unit with the Arduino and LCD screen and possibly switches which determine mode or readout. 1 module with engine and throttle controls. 1 module with action buttons. 1 module with RCS and SAS controls and 2 modules with a joystick for rotational and translation controls.

I intend to make this controller fully modular, where the modules each have their own arduino/microduino board and communicate with the base unit over a MODBUS link. But i don't want to overcomplicate things by dragging too many new things into this project. When this one works, i'll make a v2 with the MODBUS system.

20190219 : Minor corrections in UpperBasePad, UpperRCSPad, UpperActionPad

20180402 : Forget the Arduino Mega ADK. For everything to be cnnected centrally on it, it would need a 60+ pins connector, 10+ shift registers and 7 analog inputs. There is just no way to fit all that on a Mega Shield or even a custom size PCB that would still fit inside the base module. So i'll FF to implementing the fully modular design using Microduinos and RS485 adapters. I changed the BOM accordingly.