Numerical and Experimental Comparison of a Multibody Feathered Flapping Wing Model

• Grant number: 25/09789-3
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: October 06, 2025
• End date: July 05, 2026
• Field of knowledge: Engineering - Mechanical Engineering - Mechanics of Solids
• Principal Investigator: Douglas Domingues Bueno
• Grantee: Renan Cavenaghi Silva
• Supervisor: Daniel Garcia Vallejo
• Host Institution: Faculdade de Engenharia (FEIS). Universidade Estadual Paulista (UNESP). Campus de Ilha Solteira. Ilha Solteira , SP, Brazil
• Institution abroad: Universidad de Sevilla (US), Spain
• Associated to the scholarship: 23/04325-3 - Aeroelastic Dynamics and Control of Micro Unmanned Air Vehicles in Formation Flight, BP.DR

Abstract

Natural selection is the mechanism from Nature responsible for selecting traits that increase the odds of an individual surviving. This mechanism resulted in the development by some species of the ability to fly. Flight in Nature is possible using a reciprocating motion of their wings in an up and down motion, generating the lift and thrust required to maintain flight. This subject gained attention from the research community due to the benefits of the flapping flight at small and medium scales that resulted in a newer Flapping Wing Unmanned Aerial Vehicle (FWUAV) configuration. Birds are unique examples due to their outstanding aerial capabilities and diversity, specializing in different aspects such as stealth, speed and endurance. A unique trait of birds is that their wings and bodies are entirely covered by feathers, which contrasts with conventional wings, since instead of a continuous surface, the feathered wing is composed of a set of discrete and overlapping surfaces. The feathered wing design enables adjacent feathers to have distinct deflected shapes, resulting in the formation of gaps between them. These gaps provide an additional air path that affects the generation of aerodynamic loads during the flapping pattern. On the other hand, due to the contact forces arising in the overlapping regions, this deflection is not arbitrary, but subject to unilateral constraints.Modeling the feathered wing design is challenging mainly due to the nonlinear characteristics of the contact between feathers. In this context, this research project involves developing a structural dynamic model for a flapping feathered wing and performing experimental tests to support the theoretical predictions. To this end, numerical models for the feathering wing are proposed by obtaining the equation of motion of each model undergoing an imposed motion at its attachment. Then, the equations of motion are numerically integrated and the trajectories of each model are compared with the experimental data. (AU)