Identifying and intercepting prohibited items and explosives is a critical focus of aviation security. While computed tomography (CT) systems represent the industry standard for detecting explosives in baggage, x-ray diffraction imaging (XRDI) systems have shown increasing performance and commercial viability. Our approach to explosives detection involves the combination of CT and XRDI into a single, hybrid system where both the CT and XRDI data are utilized in the reconstruction and classification algorithms. In this work, we focus on comparing multiple reconstruction and classifier implementations and quantifying the resulting performance. Our analysis shows higher quality reconstructions lead to improved material separability, better classification performance (detection and false alarm rates), and reduces model uncertainty. Through this work, we demonstrate the relationship between improved quality of reconstructions and the separability of threat from non-threat objects in the domain of explosives detection.
The ability to determine the atomic structure or identify the material composition of a sample at high spatial resolution is paramount to a variety of research, imaging, and inspection tasks. We have developed a multi-modality x-ray transmission and x-ray diffraction imaging system that is compact and enables scanning of intact samples. To demonstrate the capabilities of the system, we characterize its spatial and momentum transfer resolution and provide examples of the contrast and utility of the system using a combination of resolution and anthropomorphic phantoms.
X-ray diffraction imaging (XRDI) offers the potential for reduced false alarm rates, increased throughputs, and more sensitive explosives detection performance in aviation security applications. The deployment of computed tomography (CT) systems across carry-on and checked baggage screening lanes has both reinforced the need for orthogonal detection technologies and created an exciting new opportunity for the implementation of XRDI. Our team at Quadridox built a novel XRDI system that, when combined with a CT system, realizes full-tunnel assessment of checked bags at a belt speed of 20 cm/s. We integrated our XRDI system with a Smiths CTX 5800 explosives detection system (EDS) and collected bag data containing both benign and threat objects. We describe the XRDI system, show examples of the resulting hybrid CT and XRD dataset, and present performance results for the hybrid system.
To allow for fast, automated inspection of checked baggage with low false alarm rates, we designed and built a novel X-ray diffraction (XRD) system to use in a hybrid CT+XRD configuration, where each bag is scanned by both CT and XRD systems. Our XRD system is modular, vendor agnostic, and operates inline with the CT system at belt speed with full-tunnel coverage. In this work, we demonstrate reduced false alarm rates (relative to CT alone) with our XRD system placed inline and integrated mechanically and via software with a Smiths CTX 5800 (a certified EDS system) for fully-automated material-based alarm decisions.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.