Instrumenting a Flapping Wing Air Vehicle System for Free Flight Measurement

Abstract

Flapping wing flight is a challenging system integration problem for designers due to tight coupling between propulsion and flexible wing subsystems with variable kinematics. Due to the fluid-structure interactions present in such a system, models must be tailored to a particular design instantiation to provide high accuracy and a clear picture of underlying physical phenomena. However, a practical design approach requires an extensible model that enables exploration of several design alternatives. The difficulty of generating models that are both highly accurate and extensible suggest a combined experimental and simplified modeling approach may offer a more tractable approach to system design and integration. However, experimental data on flapping wing air vehicles that is collected in a static laboratory test or a wind tunnel test is limited because of the rigid mounting of the vehicle, which alters the natural body response to flapping forces generated. Therefore, we undertake the design of a flapping wing air vehicle system that is instrumented to provide data that may be used to create and validate a simplified aerodynamics model that is capable of freely flying. The sensor suite includes measurements of attitude, heading, altitude, position, wing angle, as well as voltage and current supplied to the drive motors. With this approach, a complete energetic picture of flight is constructed, and by varying the parameters of the vehicle, the envelope of feasible performance is investigated. Finally, the results of the experimental testing are compared to a simplified aerodynamic model to establish the effectiveness of the proposed approach to system design.