Non-invasive ultrasonic instrument for counter-terrorism and drug interdiction operations - the acoustic inspection device (AID)

Abstract

The Pacific Northwest National Laboratory (PNNL) has developed a portable, battery-operated, handheld ultrasonic device that provides non-invasive container interrogation and material identification capabilities. The technique governing how the acoustic inspection device (AID) functions, involves measurements of ultrasonic pulses (0.1 to 5 MHz) that are launched into a container or material. The return echoes from these pulses are analyzed in terms of time-of-flight and frequency content to extract physical property measurements (the acoustic velocity and attenuation coefficient) of the material under test. The AID performs an automated analysis of the return echoes to identify the material, and detect contraband in the form of submerged packages and concealed compartments in liquid filled containers and solid-form commodities. This device utilizes a database consisting of material property measurements acquired from an automated, ultrasonic fluid characterization system called the Velocity-Attenuation Measurement System (VAMS). Both prototype technologies are discussed here. This manuscript describes the functionality, capabilities and measurement methodology of the technology as it relates to the material property measurements and homeland security applications.