Achieving Traceability of Industrial Computed Tomography

TLDR

Traceability is essential for complex measurement techniques such as coordinate measuring machines, and while model‑based uncertainty budgets and empirical approaches exist for tactile probes, their application to computed tomography remains under development. The study evaluates the measurement uncertainty of industrial computed tomography by integrating existing empirical methods and knowledge to assess their applicability for industry users. The authors analyze dimensional CT measurement influences using data from a current industrial micro‑CT system.

Abstract

Achieving traceability is crucial for complex measurement techniques, especially for coordinate measuring machines (CMMs). For CMMs using tactile probes, traceability can for certain measurements be achieved using model-based uncertainty budgets. Up to now, uncertainty simula-tions could be used applicable only for tactile CMM measurements of regular geometries, but are available as an add-on for different CMMs. This procedure is accepted by guidelines and inter-national standards (VDI/VDE 2617-7, supplement 1 [1] to GUM). Furthermore, empirical ap-proaches to assess the measurement uncertainty by means of calibrated workpieces or prior know-ledge exist or are under development. These approaches can as a matter of principle also be used for CMMs featuring computed tomography (CT). In this paper, the empirical assessment of the mea-surement uncertainty of the upcoming measurement technology CT [2, 3] will be discussed uniting the present approaches and the current knowledge, with the focus being on the applicability of con-cepts for users in industry. For this purpose, the influences on dimensional CT measurements are analyzed and evaluated, taking the measurement data of a current industrial micro CT system as a basis.