3ds Max Animation :: Drive Angled Wedge Sideways

I have a post that can only move up and down and I want to be able to drive an angled wedge sideways under it and back again, such that the post is progressively lifted by the wedge as it moves further under the post and then goes down again. How do I link this? I tried creating a path that coincides with the angle of the wedge and linking the post to that with it set to only inherit movement on the vertical, but that doesn't work. I will also need to do this with a wedge that has a wavy leading edge so that the movement of the post up and down is not linear, but follows the shape of the wave.

Perhaps another analogy would be to have a car drive over a hilly terrain, but instead of the car moving, the terrain is moving sideways under the car, which stays in the same position but moves up and down with the terrain (and the car's orientation is always horizontal (i.e. doesn't pitch its nose up and down).