Experimental investigation of flapping mechanism of the black-headed gull in forward flight

Abstract

Many developments in aerospace science have originated from nature. One of these developments has been obtained through inspirations from flying locomotion. The aim of this study is to simulate the flapping mechanism of the black-headed gull in forward flight. The wing of the black-headed gull is characterized entirely by complex dihedral, dividing the wing into two distinct parts. Hence, a flapping mechanism with different bending deflection angles is constructed and compared with a primitive flapping mechanism. Firstly, parametric studies are conducted to assess the role of flapping frequency, velocity and bending deflection angle on the lift, thrust and power loading of the membrane flexible wing at 10 ° angle of attack. Secondly, dimensional analysis is used to establish the similarity between the real gull and the constructed mechanism. Superiority of the bending deflection mechanism is concluded in forward flight against simple flapping wing in terms of aerodynamic forces as well as power loading parameter. It is found that although the aerodynamic coefficients decrease with increase in advance ratio, the best power loading of the black-headed gull is obtained between advance ratio of 2 and 3, in the gull's aerodynamically quasi-steady regime.

Effects of smart flap on aerodynamic performance of sinusoidal leading-edge wings at low Reynolds numbers

“…The hysteresis, non-repeatability, and nonlinearity of force sensors are less than 0.02% of full scale (3 kg and 6 kg). 53,54 The relative uncertainty in force coefficients was determined to be less than 1%. As shown in Figure 5, the load cells are connected to a stepper motor (model ZhengKe motor ZGA42FH) and a stand at the top of the wind tunnel.…”

Experimental study of low Reynolds number effects on aerodynamics of smooth and sinusoidal leading-edge wings in the vicinity of the ground

“…This value for turbulence intensity is much less than that mentioned by Mueller [28]. In order to measure lift and drag forces, two one-dimensional loadcells previously used in [29,30] are employed. The hysteresis, non-repeatability, and non-linearity of force sensors are less than 0.02% of full scale (3 kg and 6 kg).…”

Recent advancements in flapping mechanism and wing design of micro aerial vehicles

“…46 The third category includes foldable wing designs inspired by Bats and other birds. 15,16,47 The MAV developed on these lines includes BATMAV 40 developed by Bunget in 2008.…”

“…Bird and insect-based Micro Air Vehicles (MAVs) differ from each other based on their size, wing design, and kinematics and control mechanisms. Bird inspired MAVs [13][14][15][16][17] require an initial launch speed, lift, and thrust which is produced by flapping motion of their wings. Hence, they cannot take off vertically or hover (except for hummingbird).…”