satbot
allows you to read and use the serial data output by common hobby R/C satellite receivers. It is possible to simply get the relative "stick" and switch positions, which is very convenient for embedded/robotic projects.
Note that only Spektrum brand DSMX satellite receivers have been tested to-date, but Futaba and off-brand DSM2/DSMX receivers should work, possibly with additional fiddling.
satbot
was created with embedded systems like the Raspberry Pi in mind, but all that is really needed is a TTL serial-usb cable (such as this one.)
Assuming your satellite receiver is already bound to your transmitter and you've connected it via a USB dongle it should be possible to simply:
satbot start --foreground /dev/ttysXXX
At the command line, where /tmp/ttysXXX
is the serial device associated with your receiver.