Recent years have seen an increasing interest in micro aerial vehicles (MAVs) and flapping flight in connection to that. The Delft University of Technology has developed a flapping wing MAV, “DelFly II”, which relies on a flapping bi-plane wing configuration for thrust and lift. The ultimate aim of the present research is to improve the flight performance of the DelFly II from both an aerodynam...

In this paper, a piezoelectrically actuated four-bar mechanism with two flexible links is proposed to be used in a micromechanical flying insect robot wing thorax for stroke amplification. PZT-5H and PZN-PT based unimorph actuators are utilized at the input link of the four-bar for a compact and light weight thorax transmission mechanism. The kinematics and dynamics of the proposed wing structu...

We have studied the passive maintenance of high angle of attack and its lift generation during the crane fly's flapping translation using a dynamically scaled model. Since the wing and the surrounding fluid interact with each other, the dynamic similarity between the model flight and actual insect flight was measured using not only the non-dimensional numbers for the fluid (the Reynolds and Str...

Flapping wings are important in many biological and bioinspired systems. Here, we investigate the fluid mechanics of flapping wings that possess a single flexible hinge allowing passive wing pitch rotation under load. We perform experiments on an insect-scale (≈1 cm wing span) robotic flapper and compare the results with a quasi-steady dynamical model and a coupled fluid–structure computational...

The effect of a wind gust on the aerodynamic characteristics of a rigid wing undergoing insect-based flapping motion is studied numerically. The turbulent flow near the flapping wing is described by the 3-D unsteady compressible Reynolds-Averaged Navier-Stokes equations with the Spalart-Allmaras turbulence model. The governing equations are solved using a second-order node-centered finite volum...

Recent work on the aerodynamics of flapping flight reveals fundamental differences in the mechanisms of aerodynamic force generation between fixed and flapping wings. When fixed wings translate at high angles of attack, they periodically generate and shed leading and trailing edge vortices as reflected in their fluctuating aerodynamic force traces and associated flow visualization. In contrast,...

Most biological flyers undergo orderly deformation in flight, and the deformations of wings lead to complex fluid-structure interactions. In this paper, an aerodynamic-structural coupling method of flapping wing is developed based on ANSYS to simulate the flapping of flexible wing. Firstly, a three-dimensional model of the cicada’s wing is established. Then, numerical simulation method of unste...

The effect of wing flexibility in hoverflies was investigated using an at-scale mechanical model. Unlike dynamically-scaled models, an at-scale model can include all phenomena related to motion and deformation of the wing during flapping. For this purpose, an at-scale polymer wing mimicking a hoverfly was fabricated using a custom micromolding process. The wing has venation and corrugation prof...

Research in the field of Flapping Wing Micro Air Vehicle (FMAV) is an ongoing quest to master the natural flyers by mechanical means. The field is characterized by unsteady aerodynamics, whose knowledge is still developing. Birds and insects have different methods of producing lift and thrust for hovering and forward flight. Most birds, however, cannot hover. Wing tips of birds follow simple pa...