Dizionario di metrologia

Metrology is the science and technique of measuring.

Measure is above all information: characteristics and properties of objects and phenomena are measured to better understand, and therefore use, nature and human products. Once the information has been acquired, it is used to decide: whether the tolerances envisaged by the project have been respected; whether to accept a supply that has been proposed with guaranteed characteristics; whether to intervene on a process because some of its characteristics may reach dangerous thresholds.

Measurement is high-profile information, as it allows us to quantitatively translate the relationships between objects and the models that describe them. In practice, there is no decision that has not been preceded by measures, and there is no meaningful and organised plan without measurement.

Coordinate Measuring Machine (CMM): a measuring system that is able to move a ‘feeler’ or probing system and bring it into contact with the object to be measured to determine the spatial coordinates on its surface.

A CMM is called manual if the moving elements of the machine are moved directly by the operator, at CNC (Computerized Numerical Control) if the moving elements of the machine are moved by servo motors controlled by a PC-assisted government unit.

The application software, through its own calculations and algorithms, determines the dimensional and geometric characteristics of the object.

Scan: the generation of a point cloud for the construction of profiles or surfaces.

Digitisation: the process of transforming an image obtained by scanning an object into a digital format (i.e. interpretable by a computer) into, for example, a three-dimensional mathematical model.

Mathematical model: a system of complex equations representing three-dimensional objects.

Calibers: dedicated equipment, including instrumentation, for measuring products.

Template: a specific type of equipment for the positioning of objects or parts of objects subjected to measurement testing.