I'm trying to design and build a hinge for a door that needs to open in a fairly complicated motion.

After having a detailed look at some concealed kitchen cabinet hinges, and googling around, I'm still not sure how to go about this. I could get some lego struts and pins, and try some ideas out, but I'm wondering if anyone knows of some resources on the Internet, where I can learn more about designing complicated joints?

Cheers,

Matt