With regard to accurate determination of component size and dimension it is important to utilize positioning apparatus which can be readily and smoothly manipulated in order to determine dimension {acute over (ω)}. Generally a stylus is presented upon a carriage associated with a column is utilized for displacement between positions on a component surface. By displacement of the stylus and associated electronic devices it is possible to determine accurately the dimensions of a component. Displacement must be smooth and accurate as well as repeatable.