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Two image-based sensing methods are merged to mimic human vision in support of airborne detect-and-avoid and counter–unmanned aircraft systems applications. In the proposed sensing system architect...

This study aims to enable solid-state aerodynamic force generation in high-dynamic-pressure airflow. A novel, high-load-output, bidirectional variable-camber airfoil employing a type of piezoceramic composite actuator known as a Macro-Fiber Composite is presented. The novel airfoil employs two active surfaces and a single four-bar (box) mechanism as the internal structure. The unique choice of boundary conditions allows variable and smooth deformation in both directions from a flat camber line. The paper focuses on actuation modeling and response characterization under aerodynamic loads. A parametric study of aerodynamic response is employed to optimize the kinematic parameters of the airfoil. The concept is fabricated by implementing eight Macro-Fiber Composite 8557-P1-type actuators in a bimorph configuration to construct the active surfaces. The box mechanism generates deflection and camber change as predicted. Wind-tunnel experiments are conducted on a 12.6% maximum thickness, 127 mm chord airfoil. Aerodynamic and structural performance results are presented for a flow rate of 15 m /s and a Reynolds number of 127,000. Nonlinear effects due to aerodynamic and piezoceramic hysteresis are identified and discussed. A lift coefficient change of 1.54 is observed purely due to voltage actuation. Results are compared with conventional, zero-camber NACA and other airfoils. A 72% increase in the lift-curve slope is achieved when compared with a NACA 0009 airfoil.

A reproduction of the Wright 1901 Glider, built by The Wright Experience TM in Warrenton, Virginia, was wind tunnel tested at the Langley Full Scale Tunnel through a range of conditions similar to what was experienced 100 years ago. The testing included a range of dynamic pressures that encompassed the stall and maximum gliding speeds, angles of attack up to 20 ∘ , and sideslip angles of up to 15 ∘ . The results of the test were used to determine not only lift, drag and moment coefficients, but also control power from the actuation of the canard and wing warping controls. A glide ratio measurement of 3.9:1 was recorded and compared to the observations of the Wrights. Simulations of longitudinal and lateral dynamics showed that the aircraft was controllable, although adverse yaw from wing warping caused the aircraft to turn opposite of the commanded roll. Longitudinal stability was found to be a function of angle of attack and the condition of the wing covering, resulting in static margins that varied greatly.