NeoMoses,
How about a cheap Plc, (programable logic controler)?
That's what they are made for. To turn things on and off and time things or to sense presure or voltages, current ect....
I don't know tons about them, but maybe someone here does.
I also have a friend that works with this stuff for a living.
I could ask if need be.
Here's a quick link:http://www.thomasregister.com//Catal...1&uuid=TRGuest
Sorry this link doesn't get you all the way to the plc's. So you'll have to navigate to them> products>plc.
Then look at the Nano series. They have starter packages.