on the first impression - it sounds not so hart to achieve - till i started to played around with the idea...hehe
I came up with a simple rigid bind. Bound each bone to the correct part of the geomerty and connected the rotationaxis via set driven key to each other. This will look ok cause it's a linear movement.
So the job is only some connecting. In the test I started with the rotation of the root joint as my first key. That moves the whole piece. Since a translation of the root joint in x, y or z will move the whole rig I would recommend to bring in a locator or some geometry to start the initial movement.
There are defiantly many more elegant solutions via mel, but as long as you don't know how to work with expressions- it's useless. In my opinion it's no real help to copy another guys script without having a clue how it works. So my strong advice : Get used to mel. It's so powerful and can save you a hell of work.
hope that helps
..the Force is with me (sometimes)