Experimental analysis of aerodynamic performances of dragonfly wings

Nature-inspired flying robots are beneficial than other multi-rotor or fixed wing analogs, in many aspects. As wings play the key role on the hovering and maneuvering conditions of flying insects, structural functions and aerodynamic performances of the insect wings are needed to be analyzed for designing more effective wings for insect-sized flying robots. This study describes the method for experimental analysis of aerodynamic and vibration characteristics of dragonfly (Erythemis Simplicicollis) forewings and hindwings. Vibration testing of the dragonfly wings has been conducted to obtain natural frequencies and mode shapes of the wings. The wings have also been examined in a suction wind tunnel having pistol-grip sting balance to illustrate the vibration and aerodynamic characteristics. The structural aerodynamic response of the wing has been determined at different freestream velocities and at different angles of attack. From the experimental results, the deformation response and the coefficients of drag and lift of the insect wings have been obtained for different Reynolds numbers and angles of attack. The coefficient of lift of the wings increases with the Reynolds number and angle of attack. The coefficient of drag of the wings also increases with the Reynolds number and angle of attack.