Experimental study on thrust and power of flapping-wing system based on rack-pinion mechanism.
This experimental study investigates the effect of three parameters: wing aspect ratio (AR), wing offset, and flapping frequency, on thrust generation and power consumption of a flapping-wing system based on a rack-pinion mechanism. The new flapping-wing system is simple but robust, and is able to create a large flapping amplitude. The thrust measured by a load cell reveals that for a given power, the flapping-wing system using a higher wing AR produces larger thrust and higher flapping frequency at the wing offset of 0.15[Formula: see text] or 0.20[Formula: see text] ([Formula: see text] is the mean chord) than other wing offsets. Of the three parameters, the flapping frequency plays a more significant role on thrust generation than either the wing AR or the wing offset. Based on the measured thrusts, an empirical equation for thrust prediction is suggested, as a function of wing area, flapping frequency, flapping angle, and wing AR. The difference between the predicted and measured thrusts was less than 7%, which proved that the empirical equation for thrust prediction is reasonable. On average, the measured power consumption to flap the wings shows that 46.5% of the input power is spent to produce aerodynamic forces, 14.0% to overcome inertia force, 9.5% to drive the rack-pinion-based flapping mechanism, and 30.0% is wasted as the power loss of the installed motor. From the power analysis, it is found that the wing with an AR of 2.25 using a wing offset of 0.20[Formula: see text] showed the optimal power loading in the flapping-wing system. In addition, the flapping frequency of 25 Hz is recommended as the optimal frequency of the current flapping-wing system for high efficiency, which was 48.3%, using a wing with an AR of 2.25 and a wing offset of 0.20[Formula: see text] in the proposed design.
Department of Advanced Technology Fusion and Artificial Muscle Research Center, Konkuk University, Korea.
Tuan Anh
TA
Nguyen
Hoang
H
Vu Phan
Thi Kim Loan
TK
Au
Hoon Cheol
HC
Park
D000818:Animals; D001696:Biomechanical Phenomena; D040761:Biomimetic Materials; D032701:Biomimetics; D003187:Compliance / Q000502:physiology; D003198:Computer Simulation; D004867:Equipment Design; D005426:Flight, Animal / Q000502:physiology*; D008954:Models, Biological; D009068:Movement / Q000502:physiology; D012399:Rotation; D014921:Wings, Animal / Q000033:anatomy & histology / Q000502:physiology*