Attached is an assembly with two parts. I've been messing with this in a larger assembly for the last couple days. For some reason the linear motor is not working for me. It works in the animation but not in the motion analysis. Another thing I think is odd is that the item to move "disappears" once you say ok. When you open it up there is nothing selected for the part to move.

I'm not sure if I'm doing something wrong or if this is a bug.

If I'm screwing this up how do I get the shaft to move back and forth in a motion study the same way it does in the animation?

Thanks,