Design and Research on Mechanism of Bionic Flapping-wing Air Vehicle

Abstract

The fly mechanism and motion characteristics of the birds were analyzed. By the bionics principle, a new bionic flapping wing mechanism was proposed in order to imitate the motion of bird wing. The virtual prototype of this mechanism was established through ADAMS, then the kinematic simulation analysis was applied to the prototype in order to validate the feasibility of this mechanism. And a computational fluid dynamics software, named Fluent was employed to analyze the aerodynamic force of bionic wing. These results shorten the period of manufacturing of flapping wing mechanism, and can provide theoretical basis for the research and manufacture of bionic flapping wing robot. The Flapping-wing Air Vehicle (FAV) based on bionics is a sort of new aircraft which imitates birds. Compared with the traditional fixed wing and rotor aircraft, setting the lift, hovering and push functions in a flapping wing system is the main characteristics of Flapping-wing Air Vehicle and it has strong maneuverability (1). Flapping-wing Air Vehicle has advantages of high maneuverability, low noise, low cost, multifunction and potential applications to the modern war. In view of the FAV has great advantages in military and civilian applications, research institutions and universities around the world design various types of FAV. Research on this field has also been conducted in China. At present, the successful flight of FAV mostly adopts single crank rocker mechanism, such as MAV developed by northwestern polytechnical university (2). Although single crank rocker mechanism can achieve predetermined flapping frequency and angle, but itself is a symmetrical structure. The motion of both sides wings is asymmetry in the process of flapping flight and affects the flight stability and security. This paper analyzes the movement characteristics of bird wings from the perspective of bionics. A symmetric double sections flapping wing mechanism is designed in order to imitate the motion of bird wing. The virtual prototype of this mechanism is established through ADAMS, then the kinematic simulation analysis is applied to the prototype in order to improve the quality of the flapping wing flight. For the problem of the unsteady aerodynamic of flapping wing flight, by using the method of numerical simulation, the aerodynamic force is analyzed. The wing and tail are designed in the end. All these works are supposed to find the best design scheme and achieve sustainable flapping wing flight. 2. Design and Simulation Analysis of The Flapping -wing Mechanism