I'm not sure where you could get a machine, but, there are companies who do shock and vibration testing to certain mfrs specs. Look at
http://www.swri.org/4org/d18/mechflu/strudyn/home.htm
They have an awesome earthquake machine. Contact me if you need more info, maybe I could come up with a...
Are you familiar with relations? Get the symbol for the dimensions you need to deal with and use them in the equation. You can also change the name of the symbols to make your equation more user friendly. Within the relations you can also set variables to be used later.