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Robinson, Alex Lockwood

Publications and source records attributed to Robinson, Alex Lockwood.

Development of MEMS Photoacoustic Spectroscopy

After years in the field, many materials suffer degradation, off-gassing, and chemical changes causing build-up of measurable chemical atmospheres. Stand-alone embedded chemical sensors are typically limited in specificity, require electrical lines, and/or calibration drift makes data reliability questionable. Along with size, these "Achilles' heels" have prevented incorporation of gas sensing into sealed, hazardous locations which would highly benefit from in-situ analysis. We report on development of an all-optical, mid-IR, fiber-optic based MEMS Photoacoustic Spectroscopy solution to address these limitations. Concurrent modeling and computational simulation are used to guide hardware design and implementation.

36 MATERIALS SCIENCE↗

Selective stress-based microcantilever sensors for enhanced surveillance

Assessment of component aging and degradation in weapon systems remains a considerable challenge for the Integrated Stockpile Evaluation program. Analysis of weapon atmospheres can provide degradation signatures and indicate the presence of corrosive vapors. However, a critical need exists for compatible in-situ sensors to detect moisture and other gases over stockpile lifetimes. This inhibits development of both “self-aware weapons” and fully instrumented weapon test platforms that could provide in-situ data to validate high-fidelity models for gases within weapons. We developed platforms for on-demand weapon atmosphere surveillance based on static microcantilevers (SMC) and surface accoustic wave (SAW) devices coated with nanoporous metal organic frameworks (MOFs) to provide selectivity.

Allendorf, Mark D.↗