Hello and thanks for asking, as a matter of fact, I managed to finish the load sensitive cruise control using an Arduino controller, under a research proposal of the National Science Foundation. I used the vacuum sensor as long as the speed was maintained withing an upper and lower limit. As soon as it went out of the limit, the system returned to normal operation to control the speed, until it again reached the speed limits. The system works fairly well, but still needs some refinement, I am using a PID algorithm designed by me, but I need some help in such program, so anyone out there that has any ideas will be greatly appreciated. I am including a Scribd link to the power point presentation I had to make for the NSF Symposium offered on March 12, 2011.
Load Sensitive Adaptive Cruise Control
I am also including a Youtube link of the video when I presented, it's in Spanish.
Video of the presentation
Hope this information is helpful and any ideas, just let me know.