Here’s a wireless controller for a tunable laser (tunable meaning the wavelength could be adjusted) I designed awhile ago. The laser was housed in a separate laboratory in the basement to the one in which it was often used and there was a lot of concrete in between. Solving this problem allowed the scientists to tune the laser easily and also enabled them to make measurements while sweeping the wavelength to aid in the characterization of semiconductor nanostructures.
Since cost was also a factor my solution was to build a wireless controller using inexpensive parts one could find at Sparkfun Electronics. I wanted to make the interface fun and intuitive so I used an SNES controller for the input device, powered by an arduino board and xbee radios for the wireless communication. On the receiver end I added another arduino because although I could have got away without it I wanted to leave some room for expandability in the future in case any future engineer or scientist had something to add to the system.
I used a stepper motor and stepper motor controller from Sparkfun to drive the whole thing. The xbee radios worked remarkably reliably in the basement even with all the concrete between the two radios.
This project was made it on Hackaday awhile ago.