IMTC 2003 – Instrumentation and Measurement Technology Conference Vail, CO, USA, 20-22 May 2003 Non-Invasive Ultrasonic Instrument for Counter-Terrorism and Drug Interdiction Operations – The Acoustic Inspection Device (AID) Aaron A. Diaz, Brion J. Burghard, James R. Skorpik, Chester L. Shepard, Todd J. Samuel, and Richard A. Pappas National Security Directorate, Pacific Northwest National Laboratory, PO Box 999, Richland, Washington, 99352, USA Phone: +1-509-375-2606, Fax: +1-509-375-6736, Email: aaron.diaz@pnl.gov 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 material property measurements and homeland security applications. I. INTRODUCTION The rapid interrogation of sealed containers and bulk-solid commodities is a critical task for personnel charged with enforcing government policies, maintaining public safety, and ensuring national security. In recent years, events such as the bombings of Pan Am Flight 103 over Scotland, the World Trade Center in New York City, the Murrah Building in Oklahoma City, Centennial Park in Atlanta, and US Embassies in East Africa have riveted increasing political, media and public attention on the threat and impact of terrorism to our society and economy. In 1995, the release of the nerve agent sarin in the Tokyo subway system by Aum Shinrikyo and the discovery of a vast Iraqi network and infrastructure for the development of biological and chemical weapons have continued to bring the issues of counterterrorism to the forefront in America. Finally, the events of September 11 th , 2001, served as the ultimate blow that contributed to Americans realizing we are not invincible or untouchable. With the ever-increasing prominence of methamphetamine production and other illicit substances, a second driver for development of advanced technology to support law enforcement efforts has been introduced into the equation. The war on drugs and our new war on terrorism have revived and focused our attention on the vulnerability of our society and have provided the impetus for the development of scientific and technological advances in support of our efforts to stem the flow of contraband and weapons of mass destruction (WMD). America’s science, engineering and technology infrastructure plays a critical role in addressing these issues and providing solutions toward the detection, identification, response and resolution of substances and materials associated with smuggling and terrorist activities. The acoustic inspection device (AID), shown in figure 1, is a portable, battery-operated, handheld ultrasonic inspection platform that provides non-invasive container/material examination and identification capabilities. Fig. 1. The acoustic inspection device (AID). The AID system provides the inspector with the capability to rapidly examine sealed, liquid-filled containers and large bulk-solid commodities, a requirement facing the law enforcement community, border security personnel, the military, and international treaty conventions in their efforts to support homeland defense, deter illicit drug manufacturing, stop smuggling, collect taxes and tariffs, effectively maintain inventories, and verify treaty compliance. The AID augments on-site material interrogation efforts that typically use expensive and time-consuming processes of direct sampling and laboratory analysis. Specifically, the AID provides the operator the ability to: