[Madison]

There are as many different mechanism designs as there are FIRST robots, and while some certainly work better than others, they're all largely based on similar concepts and principles.

Rather than know explicitly how an arm or elevator mechanism built by team XXXX works, I think it's far more valuable to gain understanding of common engineering mechanisms and find ways creating a solution for your design problem based upon those ideas.

Ken offers excellent advice to observe while designing such mechanisms, but I think it's important that your actual designs are based on knowledge of the best ways of accomplishing a task rather than facsimiles of things you've seen on some other team's robot.

Edit: It occurs to me that you may want to dig up teams' Autodesk Inventor Award entries and examine those for a great look at how they accomplished different tasks in their robot design.