Uncertainty Model for Systems Based on Wireless Sensor Networks for Large Scale Dimensional Metrology

Verification of dimensional compliance is becoming a crucial aspect in every kind of production, even when the size of the product to be checked is in the order of several meters. To this purpose, several tools based on different technologies, working principles, functionalities and architectures have been recently designed. Among these, a distributed flexible system based on a network of low cost infrared (IR) cameras — the Mobile Spatial coordinate Measuring System (MScMS) — has been developed. This paper proposes a model for the real time assessment of the system uncertainty referring to the measured point coordinates in the 3D space. The paper focuses on the sources of measurement uncertainty and, basing on the multivariate law of propagation of uncertainty, suggests a model for relating them to the uncertainty of a measured point.