Journal of Bionic Engineering (2024) 21:192–208https://doi.org/10.1007/s42235-023-00443-w

Experimental Study on the Efect of Increased Downstroke Duration for an FWAV with Morphing-coupled Wing Flapping Confguration

Ang Chen1  · Bifeng Song1  · Zhihe Wang1  · Kang Liu1  · Dong Xue1,2 · Xiaojun Yang1

1. School of Aeronautics, Northwestern Polytechnical University, Xi’an 710072, China 

2. Harbin Institute of Technology, Shenzhen 518055, China

AbstractThis paper is based on a previously developed bio-inspired Flapping Wing Aerial Vehicle (FWAV), RoboFalcon, which can fy with a morphing-coupled fapping pattern. In this paper, a simple fapping stroke control system based on Hall efect sensors is designed and applied, which is capable of assigning diferent up- and down-stroke speeds for the RoboFalcon platform to achieve an adjustable downstroke ratio. The aerodynamic and power characteristics of the morphing-coupled fapping pattern and the conventional fapping pattern with varying downstroke ratios are measured through a wind tunnel experiment, and the corresponding aerodynamic models are developed and analyzed by the nonlinear least squares method. The relatively low power consumption of the slow-downstroke mode of this vehicle is verifed through outdoor fight tests. The results of wind tunnel experiments and fight tests indicate that increased downstroke duration can improve aerodynamic and power performance for the RoboFalcon platform.

Keywords Flapping wing aerial vehicle (FWAV) · Downstroke ratio · Bio-inspired design · Morphing-coupled fapping