Task-Specific Acquisition Trajectories optimized using Observer Models

Abstract

Scan time is a crucial factor in industrial computed tomography (CT). With modern computers performing reconstructions in seconds or minutes, the duration for the projection acquisition, which is often in the order of hours, becomes the limiting factor. Therefore, it is desirable to reduce the number of projections in order to cut costs or allow for new applications, such as inline CT. So far, many different approaches mostly targeting the reconstruction method have been performed to optimize the outcome for undersampled data, but only few work has been conducted concerning the scan planing. Nevertheless, the commonly used circular standard-trajectories for image acquisition are highly inefficient since they do not consider the geometry of the inspected objects. It has already been shown that using workpiece-tailored instead of conventional circular trajectories can shorten scan times significantly. In this work we present an observer model based algorithm that has previously been applied in medical and industrial studies and extend it in several aspects. Subsequently, we focus on comparing different observer models that have not been used for this optimization yet and evaluate their performance for identifying valuable projections that contribute most to the reconstructed image.