As for floor boards, it looks to me like your best bets among currently available units would be the Roland FC-300 or the Liquid Foot. They are not inexpensive. There are other esoteric, hard to find, and probably costly options, for which support will not be robust. That said, as the current generation of guitar players in particular has come up with MIDI and is comfortable with it, more options are coming to market at a steady pace. i won't claim to have scoured the current landscape.
If you put a computer into the chain then other options are available, such as sending a command to a program that triggers it to send the sysex message. Perhaps there are apps available for a tablet that would do this.
Best of luck.
Hal