"Cargo Explosive Trace Detection Research"

Principal Investigator: Gary S. Settles

Sponsor: Transportation Security Agency

There are several difficult research challenges to be overcome before this becomes possible, however. The diverse nature of cargo containers and their variable sizes and load factors must be dealt with, and their interior atmospheres must be sampled without opening and unloading them. If successful this approach could be applied to sea, rail, and truck cargo containers as well.

"Thermofluid Dynamics: CD-ROMs For Engineering Education"

Principal Investigator: Gary S. Settles

Sponsor: National Science Foundation

The value of visual materials in conveying technical concepts is very well established, and is here applied in a multimedia form to the topic of thermofluid dynamics (i.e. convective heat transfer, thermodynamics, and gas dynamics), with strong emphasis on experimental and optical flow visualization. The result will be one or more CD-ROMs that can be used by instructors and students as a visual supplement to any of the standard textbooks on these topics. The major challenge addressed is that of enhancing traditional engineering education with highly-visual material not currently available, and thus conveying to students a sense of the research-laboratory experience. The project also addresses faculty development, by providing faculty with an unusual supplementary teaching tool, thus broadening their preparation beyond what is traditionally available in textbooks. Integration of technology is also addressed, in that the proposed material utilizes and exercises the students' use of computers and multimedia in the learning process.

The CD Gives Students A Look Into The Laboratory

View A Quicktime Movie Example Clip

Hypermedia Flow Visualization Project For Compressible Flow Instruction

Principal Investigator: Gary S. Settles

Sponsor: National Science Foundation

This CD-ROM contains new hypermedia materials on compressible flows for undergraduate students and faculty. Since textbooks often show only simple line diagrams of shock waves, nozzle flows, etc., our emphasis is on experimental flow visualization as a visual supplement to the standard textbooks. Included are: normal shock waves, oblique shock waves from cones and wedges, oblique shock detachment, Prandtl-Meyer expansions, Mach waves, nozzle flows, and the 3-D flow over a Space Shuttle model. These materials convey a sense of the laboratory experience, and of the physical appearance of real compressible flows. In some cases a wind- tunnel soundtrack and the interactive capability to change Mach number, cone angle, etc. are included.

Direct digital footage was obtained from experiments in the supersonic wind tunnel facility of the Penn State Gas Dynamics Lab for use in this CD-ROM. All experiments were done in air with a specific heat ratio of 1.4. The visualizations were accomplished using a 4-color directional schlieren technique (see Settles, G. S., "Colour-Coding Schlieren Techniques for the Optical Study of Heat and Fluid Flow," Intl. J. of Heat and Fluid Flow, Vol. 6, No. 1, March 1985, pp. 3-15.)

Research on the Aerodynamics of Explosive Detection Portals for Aviation Security Screening

Principal Investigator: Gary S. Settles

Sponsor: Transporation Safety Administration

U.S. Patent 6,073,499

The goal of this research project is the development of an airborne sampling scheme for the next- generation explosive detection portal (EDP) for aviation security screening. Although electrochemical detectors for trace explosives have already reached a high level of development, the sampling of such traces emitted from concealed explosives on the human body is comparatively naive. In particular, key aspects of the sampling problem involving fluid dynamics, heat transfer, and aerobiology have been essentially neglected to date.

This research project has a strong component of technology transfer and features a primarily- experimental approach making use of advanced, non-intrusive optical flow diagnostic instruments. Analysis and modeling are being carried out in order to understand the results of the experiments. The project concentrates on the aerodynamics of the transfer of trace material from a concealed simulated explosive-device on the human body to the input of an electrochemical detector. In June of 2000 Penn State was issued U.S. Patent 6,073,499 for "A Chemical Trace Detection Portal Based on the Natural Airflow and Heat Transfer of the Human Body. The PSU patent is currently licensed by GE Infrastructure, Security, a Division of General Electric Corp.

This company is the manufacturer of The EntryScan3 Walk-through vapor and particle detection portal. The portal rapidly examines individuals for concealed contraband in a non-intrusive manner. The EntryScan3 features patented ITMS technology used in GE's Itemiser and VaporTracer. The Itemiser is used for baggage screening by swiping a coupon across the item and then inserting it into the machine for sampling.

Gary S. Settles, Heather C. Ferree, Michael D. Tronosky, and Zachary M. Moyer, and William J. McGann, "Natural Aerodynamic Portal Sampling of Trace Explosives from the Human Body," FAA 3rd International Symposium on Explosive Detection and Aviation Security, Nov. 26-30, 2001, Atlantic City, NJ. (This is a large PDF file. Please be patient while it loads.)

Gowadia, H. A., and Settles, G. S., "The Natural Sampling of Airborne Trace Signals from Explosives Concealed upon the Human Body," Journal of Forensic Sciences, Vol. 46, No. 6, Nov. 2001, pp. 1324-1331.

Entry Scan 3

GE Infrastructure Security

Aerodynamics of Canine Olfaction for Unexploded Ordnance Detection

Principal Investigator: Gary S. Settles

Sponsor: DARPA

The global landmine problem has recently reached unprecedented proportions, with some 500 maimings or deaths occurring weekly due to landmines worldwide. Some plastic antipersonnel mines are no larger than a shoe polish can. Usually containing TNT but sometimes RDX or other non-volatile plastic explosives, these mines can be extremely difficult to detect. Despite an array of proposed high-tech detection schemes, trained canines outperform all other forms of landmine detection. They accomplish this by olfactory sensing of a trace explosive signal associated with a buried mine. Yet, notwithstanding their olfactory acuity, dogs are expensive to train and have short attention spans. For a variety of related reasons, field work using such trained animals with human handlers is no match for the enormity of the global landmine problem. It has thus become important to understand and eventually to mimic canine olfaction for purposes of unexploded ordnance detection. Evolution has provided an appropriate solution to the landmine detection problem, requiring only that we understand how it works. Accordingly, DARPA's Unexploded Ordnance Detection and Neutralization Program has set the goal of developing an "electronic dog's nose" which can be used reliably in the field. The recent development of electronic nose technology makes this possibility realistic, if ambitious. A variety of disciplines must come together effectively in order for this program to succeed. Not the least of these technologies is "aerodynamic sampling". Dogs sense an airborne chemical scent during the critical phase of detection. Without appropriate aerodynamic sampling, the extraordinary sensitivity of canine olfaction must fail. Research being conducted at the Gas Dynamics Lab aims gaining an understanding of the aerodynamics of the olfaction process through a series of flow visualization experiments as well as modeling efforts. Currently, flow visualization is being used to understand the aerodynamics of the canine nostril. The upper left light-scattering picture illustrates illustrates Bailey (1 year old Golden Retreiver) disturbing particles during olfaction. The schlieren picture located in the middle illustrates Bailey inhaling a warm plume of air.

G.S. Settles, D.A. Kester, and L.J. Dodson-Dreibelbis, "The External Aerodynamics Of Sniffing" In: Sensors and Sensing in Biology and Engineering, ed. F.G. Barth, J.A.C. Humphrey, and T.W. Secomb, Vienna:Springer-Verlad, 2003, pp. 323-355.

Settles, G. S., and Kester, D. A., "Aerodynamic sampling for landmine trace detection," presented at SPIE Aerosense Meeting, Orlando, April 2001, SPIE Vol. 4394 paper 108.

Research to Adapt Known Optical Shock-Wave Imaging Technology For Aviation Security Purposes

Principal Investigator: G.S. Settles

Sponsor: FAA

 The goal of this research project is to investigate the gas dynamics of an explosion onboard an aircraft using our Full-Scale Schlieren Facility coupled with a high-speed multiple-flash light source. The multiple imaging of the shock wave position allows non-intrusive visualization of complex wave motion, diffraction, and focusing inside an aircraft cabin or baggage container. The schlieren images will then be analyzed to gain shock velocity and Mach number data, as well as the overpressure produced by the shock wave. This effort is intended to provide useful information for the hardening of aircraft in order to safely contain or vent internal explosions. The schlieren image above (taken with a single 5-microsecond flash) shows the case of an explosion beneath a full-sized aircraft seat in the carry-on luggage space, where terrorism bombs have actually been planted in past incidents. The spherical shock wave produced by the explosion is clearly visible, as is direct light from the blast. Such results demonstrate that experimental verification of numerical results and studies of shock motion in an aircraft cabin environment at realistic scale are feasible.

G.S. Settles, T.P. Grumstrup, L.J. Dodson, J.D. Miller, and J.A. Gatto "Full-Scale High-Speed Schlieren Imaging of Explosions and Gunshots," Proc. 26th Intl. Conf. on High-Speed Photography and Photonics, Alexandria, VA Sept. 20-24, 2004, ed. D.L. Paisley, SPIE Paper 5580-174.

G.S. Settles, B.T. Keane, B.W. Anderson, and J.A. Gatto, "High-Speed Imaging of Shock-Wave Motion in Aviation Security Research," FAA 3rd International Symposium on Explosive Detection and Aviation Security, Nov. 26-30, 2001, Atlantic City, NJ.

B. T. Keane, G. S. Settles, B. W. Anderson, and J. A. Gatto, "Shock Waves In Aviation Security and Safety," Proc. Of the 23rd Intl. Symposium on Shock Waves, July 2001, Fort Worth, TX.