The role of wing bending deflection in the aerodynamics of flapping micro aerial vehicles in hovering flight

Abstract

Scientists have been improving the aerodynamic performance of flapping micro aerial vehicles by drawing inspiration from birds and insect flight. In this research study, first, the flapping mechanism of the black-headed gull is designed and then it is constructed in order to investigate the effects of wing bending deflection on the aerodynamic performance. Thrust generation, power consumption and power loading are considered as performance parameters. Three wings representing different underlying structures, namely flexible membrane, rigid membrane and airfoil, are fabricated with the same planform to investigate the roles of flexibility, thickness and camber. Experiments are performed for flapping frequencies ranging from 1.5 Hz to 6 Hz, 10 degrees angle of attack and no wind tunnel velocity (hovering flight). The results indicate that the aerodynamic performance is improved by using the bending deflection mechanism in comparison with the simple flapping mechanism. Moreover, we can conclude that the performance of the airfoil wing is superior to flexible and rigid wings.

Experimental investigation of ground effects on aerodynamics of sinusoidal leading-edge wings

“…Two one-dimensional strain gauge load cells (model Bongshin OBU-N49106 and OBU-N50170) are employed to measure the lift and drag forces. 48 The relative error of these force sensors is below 0.4%. The hysteresis, non-repeatability, and non-linearity of force sensors are less than 0.02% of full scale (3 kg and 6 kg).…”

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

“…The hysteresis, non-repeatability, and non-linearity 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).…”