Mechanism Design and Kinematics Analysis of a Bio-Inspired Flexible Flapping Wing

Abstract

The flapping wing presented in this paper is a novel bio-inspired underwater propulsor which emulates the swimming mode of manta ray. A combined mechanism with two sub-mechanisms, which has two degrees of freedom, namely flapping motion and chord-wise twisting, is proposed and designed to realize the similar flapping motion of manta ray. The sub-mechanism in wing- span direction, which is a two-section structure with single-slider-double-rocker mechanism, can achieve the active flapping motion of the basal part and the follow-up motion of the distal part. The sub-mechanism in chord-wise direction, which is designed to be a distributed flexibility structure, can achieve the active twisting motion of the leading part and the passive deformation of the trailing part. The direct kinematics analysis shows that the designed mechanism have good continuity and the attitude angle of the flapping wing can \( \left[ {{\raise0.7ex\hbox{${ - \pi }$} \!\mathord{\left/ {\vphantom {{ - \pi } 4}}\right.\kern-0pt} \!\lower0.7ex\hbox{$4$}},{\raise0.7ex\hbox{$\pi $} \!\mathord{\left/ {\vphantom {\pi 4}}\right.\kern-0pt} \!\lower0.7ex\hbox{$4$}}} \right] \). The control rules of motors are obtained through the inverse kinematics analysis.