Today I'm modeling the basic 3D and making some tests with the Sharp sensor. My biggest doubt was about the deflection of the IR beam and now, its ok. It's a relief.

Now I'm working on the system that will make on Z axis movimentation.

Maybe I use a fixed point of the cable on level 0m and a reel to variate the elevation. To get this data, I can use a servo motor and convert his turns to Z axis distance.