I'm glad to see the project get underway.
Do feel free to place my paper [that explains how to use a game port as an a to d] on your webpage. There are no copyrightissues. I will be happy to assist students with questions about the a to d. Though you have not on the indicated webpage mentioned anything about capacitive sensors, some of the students may want to consider using my SDC unit as well. My tutorial http://physics.mercer.edu/petepag/tutorial.html describes how it works, and I could provide one possible inexpensive schematic (<$10) for anyone wanting to use it.
Randall Peters < peters_rd@Mercer.EDU >
10 Sep 2002
See also: http://physics.mercer.edu/petepag/sens.htm