Flexible shear-stress sensor skin and its application to unmanned aerial vehicles

Shear-stress information is of great interest for many fluidic dynamic monitoring/diagnostics application. To obtain such information on non-planar surfaces has long been a significant challenge. This paper describes the development of flexible shear-stress sensor skin and its application on the detection of leading edge flow separation for delta planform unmanned aerial vehicles (UAVs). The sensor skin contains a 1-D array of 36 shear-stress sensors, which can cover the 180° surface of the 1.27 cm diameter semicylindrical UAV leading edge with 5° resolution. The implementation process of the sensor skin is significantly simplified by a packaging scheme based on solder bonding and flexible printed circuit board (PCB). The flexible shear-stress sensor skin in both wind tunnel and real flight tests detected the flow separation along the leading edge successfully.