This NASA Phase II SBIR program would develop ultra-wide bandwidth, conformal nanomembrane based strain sensors for nondestructive evaluation applications, using silicon on insulator techniques in combination with nanocomposite materials. Semiconductor nanomembrane strain sensors are thin, mechanically and chemically robust materials that may be patterned in two dimensions to create multi-sensor element skin arrays that can be conformally attached onto vehicle and model surfaces. The team will transition the conformal nanomembrane based strain sensors from their current concept to prototype stage products of use to NASA’s test facilities. The team will optimize an improved mechanical and electrical model of semiconductor nanomembrane based sensor performance that will allow quantitative optimization of material properties and suggest optimal methods for sensor attachment and use for nondestructive evaluation applications. The team will fabricate patterned two-dimensional sensor arrays and internal electronics using optimized materials. The team will perform a complete analysis of sensor cross-sensitivities and noise sources to allow optimization of signal-to-noise ratio and practical sensor sensitivity.
The advanced real-time structure health monitoring requires accurate experimental information about the crack initiation and sizing and direction in the structure. In a material under active stress, such as some components of operational vehicles during flight, ultra-width strain sensors mounted in an area can detect the formation of a crack at the moment it begins propagating.
Primary customers would be university, government laboratory and industry researchers. The technique is valuable for detecting cracks forming in pressure vessels and pipelines transporting liquids under high pressures.