A 6-DoF Dynamic Model for Falcon-Like Flapping-Wing Aircraft: Virtual Environment Design and Verification

Unsteady aerodynamics because of wing motion and underactuated caused by bionic driving mode are among the most notable challenges to accurate dynamic modeling and flight control for flapping-wing aircraft (FWAs). In this paper, we establish a comprehensive 6-degree-of-freedom (DoF) dynamic model to describe the multi-mode motion of a falcon-like FWA. The unsteady vortex lattice method (UVLM) is used to compute the time-varying aerodynamic forces on the main wing, accounting for the effects of flexible deformations and lateral dynamics. Based on a series of wind tunnel experiments, a data-driven model for the V-tail is developed using an artificial neural network (ANN) to capture the relationship between ruddervators’ deflections and aerodynamic forces. A simulation environment, constructed on the foundation of aerodynamic modeling and dynamic analysis, is validated with both open-loop and closed-loop flight data. The virtual system allows for rapid verification and optimization of the model and control parameters, which can enhance the flexibility and reliability of the development process of FWAs. Note to Practitioners—This work addresses the challenges of modeling and controlling FWAs, which are known for their exceptional agility but also pose significant difficulties due to unsteady aerodynamics and underactuated mechanisms. We develop a 6-DoF dynamic model and simulation environment for a falcon-like FWA, capturing multi-mode motion. Unlike dynamic models constrained to small perturbations around stable operating points, our approach provides a more comprehensive description of FWA dynamics across diverse flight modes. Validated with real flight data, this virtual environment is proven to be reliable and capable of supporting advanced control methods such as reinforcement learning and model predictive control. It offers a platform for optimizing FWA design and control, enhancing flexibility and reliability in practical applications while paving the way for further improvements in complex flight scenarios.