Dear Piclisters, I have this problem:

    I have to get X,Y,Z position of two granes (in spanish: grœas) that run
on parallel rails and are used to lift very big machines (most, the size of
a medium car). There are collision posibilities, wich now are avoid with the
use of the EYE!!.
    I have recived the proposition of solve the problem with an electronic
device, but I have the problem of getting the position on X,Y and Z axis to
calculate the posibility of collision.
    Have you got any idea about it ??