Aerodynamics, sensing and control of insect-scale flapping-wing flight.
There are nearly a million known species of flying insects and 13 000 species of flying warm-blooded vertebrates, including mammals, birds and bats. While in flight, their wings not only move forward relative to the air, they also flap up and down, plunge and sweep, so that both lift and thrust can be generated and balanced, accommodate uncertain surrounding environment, with superior flight stability and dynamics with highly varied speeds and missions. As the size of a flyer is reduced, the wing-to-body mass ratio tends to decrease as well. Furthermore, these flyers use integrated system consisting of wings to generate aerodynamic forces, muscles to move the wings, and sensing and control systems to guide and manoeuvre. In this article, recent advances in insect-scale flapping-wing aerodynamics, flexible wing structures, unsteady flight environment, sensing, stability and control are reviewed with perspective offered. In particular, the special features of the low Reynolds number flyers associated with small sizes, thin and light structures, slow flight with comparable wind gust speeds, bioinspired fabrication of wing structures, neuron-based sensing and adaptive control are highlighted.
Department of Mechanical and Aerospace Engineering , Hong Kong University of Science and Technology , Clear Water Bay, Hong Kong.
Wei
W
Shyy
Department of Mechanical and Aerospace Engineering , University of Alabama in Huntsville , Huntsville, AL, USA.
Chang-Kwon
CK
Kang
Department of Mechanical and Biomedical Engineering , City University of Hong Kong , Kowloon Tong, Hong Kong.
Pakpong
P
Chirarattananon
Graduate School of Engineering, Chiba University, Chiba, Japan; School of Aerospace, Mechanical and Manufacturing Engineering, RMIT University, Melbourne, Victoria, Australia.
Sridhar
S
Ravi
School of Aerospace, Mechanical and Manufacturing Engineering, RMIT University, Melbourne, Victoria, Australia; Shanghai-Jiao Tong University and Chiba, University International Cooperative Research Centre (SJTU-CU ICRC), Minhang, Shanghai, China.
Hao
H
Liu
biomimicry; flapping flight; insect scale