Metal Rubber Sensor Appliqu¿s for Rotor Blade Air

Thin film Metal RubberTM sensor appliqués have the potential to reduce the time, complexity and cost of measuring air flow-induced skin friction during the development of rotary wing and fixed wing aircraft and related systems. Metal RubberTM skin friction sensor appliqués allow near real-time detection 2D mapping of air flow conditions over surfaces of air vehicles. This is important for analysis of laminar to turbulent flow transitions, flow separation and reattachment mechanisms, and other instabilities, during rotor blade and fuselage design, blade tracking adjustments, and active flight control. The sensors act as mechano-electrical transducers to convert air flow-induced tangential surface forces into electrical output signals. They are thin and surface-mounted so cause minimal interaction with the flow, are easy to apply as an appliqué, and require no cavities or recesses other than holes to connect the sensor leads to data acquisition wiring. The material is resistant to normal aircraft fluids and solvents, can operate over a temperature range of -65 to +150C, and is capable of withstanding moderate rain and dust erosion. During Phase II, NanoSonic will • Develop an improved understanding of the operation of thin film Metal RubberTM skin friction sensors, • Standardize sensor design and sensor fabrication processes, • Develop a method to calibrate sensor elements as part of manufacturing, • Develop a means to compensate for cross-sensitivity effects, • Develop and optimize means for data acquisition, • Use developed sensors in cooperation with the NASA LaRC Subsonic Rotary Wing program to investigate rotorcraft research and development problems, and • Use and demonstrate the sensors in cooperation industry and academic colleagues. The significance of the proposed NASA Phase II SBIR program is in transitioning these sensors from analytical and FEM modeling to commercial products for experimental use by NASA and industry.