Formula for 6 DOF simulator

[Eskimo]

Recently I've started looking at building a 6 degree of freedom motion simulator.  Although it's unlikely to be built due to time, money and space constraints, I'm still looking at writing some software for it as software development is my day job.

I've been able to use SimConnect to get data from FSX but have no idea on where to go to get an idea of the math needed to translate these into actuator movements.  My aim is to get a 3d model working first then maybe build a small scale Stewart Platform as a proof of concept.

If anyone can point me in the direction of the math or formula to use, I'd appreciate it.  Please don't say to just use some pre built software and for me, building it myself is the most fun part.

Thanks.