Article
Engineering, Mechanical
Zdravko Terze, Viktor Pandza, Marijan Andric, Dario Zlatar
Summary: Insect flight research is driven by their exceptional flight capabilities. However, the complex aerodynamic phenomena make modeling insect-type flapping flight challenging. A novel mid-fidelity modeling approach is proposed to accurately calculate the aerodynamic loads on the insect-type flapping wings.
NONLINEAR DYNAMICS
(2022)
Article
Engineering, Aerospace
Sang-Gil Lee, Hyeon-Ho Yang, Reynolds Addo-Akoto, Jae-Hung Han
Summary: Flapping-wing micro air vehicles (FWMAVs) have various flight modes similar to birds and insects, which can be studied through trajectory optimization. This paper proposes a framework including a high-fidelity simulation model to consider the complex dynamics of FWMAVs and models unsteady aerodynamics with UPM and UVLM. The optimization results show that FWMAVs use pitch-up maneuver to increase altitude during transition flight.
Article
Acoustics
Natsuki Tsushima, Hitoshi Arizono, Masato Tamayama
Summary: In this paper, an aeroelastic framework is extended for geometrically nonlinear aeroelastic stability analysis. The framework allows for the prediction and study of flutter characteristics in flexible and high-aspect-ratio wings, taking into account large deformations and geometric nonlinearity.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Mechanics
Baptiste Corban, Michael Bauerheim, Thierry Jardin
Summary: This paper presents the discovery of optimal flapping wing kinematics using a deep learning surrogate model. The model is trained on a dataset of randomly generated kinematics and can quickly predict the forces experienced by the wing. Multi-objective optimization is then performed to obtain new kinematics. The results reveal two distinct families of motions promoting high efficiency and high lift.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Engineering, Mechanical
Zdravko Terze, Viktor Pandza, Marko Kasalo, Dario Zlatar
Summary: Research on developing a flapping aerial vehicle inspired by insects' aerial capabilities involves creating a quasi-steady aerodynamic model and an optimization algorithm based on discrete mechanics and optimal control. This approach allows for optimization of the flapping patterns of the vehicle, leading to effective and robust results in standstill hovering, as demonstrated by numerical test cases.
NONLINEAR DYNAMICS
(2021)
Article
Engineering, Aerospace
Jianghao Wu, He Yan, Chao Zhou, Yanlai Zhang
Summary: The study found that in forward flight, a flapping rotary wing demonstrates reduced thrust and lift as well as enhanced rotational moment, mainly due to changes in aerodynamics on the retreating side. Factors such as a larger advance ratio and severe forward tilt of the rotational plane are disadvantageous for thrust production, but beneficial for enhancing the rotational moment.
AEROSPACE SCIENCE AND TECHNOLOGY
(2021)
Article
Engineering, Aerospace
Xinyu Lang, Bifeng Song, Wenqing Yang, Xiaojun Yang, Dong Xue
Summary: This study analyzed the influence of wing shape and flapping motion on the hovering flight of flapping wing micro air vehicles (FWMAVs). A sensitivity analysis was conducted to evaluate the degree of influence of each parameter on aerodynamic performance, and exponential relationships were established between the parameters and aerodynamic properties. The results showed that wing area had the largest influence on lift, and the distribution of area had the most significant effect on aerodynamic power. Flapping frequency had a greater impact on lift growth and power loading, while the shape of the flapping motion primarily influenced lift and power loading, and the sweeping motion dominated power consumption.
Article
Computer Science, Interdisciplinary Applications
Cibin Joseph, Ranjith Mohan
Summary: This study introduces an object-oriented free-wake solver for multi-rotor and fixed-wing systems, highlighting its advantages and optimizations. By examining the time complexity of vortex lattice methodology and leveraging features of multi-core systems, computational performance is improved to simulate aircraft effectively.
COMPUTERS & FLUIDS
(2021)
Article
Automation & Control Systems
Xiaoyang Wu, Wei He, Qiang Wang, Tingting Meng, Xiuyu He, Qiang Fu
Summary: This article describes the design of an eagle-like flapping-wing robot with a vision system and flight control system. It has a wingspan of 1.78m and a mass of 985g. Even with a 165g vision module, the robot can fly for more than 1 hour at a speed of 5.9m/s.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Mechanics
Zhanzhou Hao, Bo Yin, Prasert Prapamonthon, Guowei Yang
Summary: Through numerical simulation, it is found that the swimming speed of penguins mainly relies on the adjustment of feathers rather than wing flapping. The optimal feathering angle is crucial for achieving the highest swimming efficiency, and the outer three-fifths of the wing contribute 85.4% of thrust generation.
Article
Robotics
Cristina Ruiz, Jose Angel Acosta, Anibal Ollero
Summary: Flapping wing robots are potentially safe and efficient platforms for near-human operations, and their automation needs to be accompanied by increased payload capacity. This study presents a new passive morphing wing prototype for enhancing the payload of such UAVs. The prototype utilizes a biased elastic joint and includes modeling, simulation, and optimization schemes for customization to different flapping wing robots. Flight experiments validate the model and demonstrate a lift increase of up to 16% and an estimated consumption reduction of 10% for the morphing prototype.
IEEE ROBOTICS AND AUTOMATION LETTERS
(2023)
Article
Mechanics
Haithem E. Taha, Laura Pla Olea, Nabil Khalifa, Cody Gonzalez, Amir S. Rezaei
Summary: Differential geometric control theory combines differential geometry and control theory, providing a tool for analyzing symmetry-breaking and unconventional force-generation mechanisms in fluid mechanics, with potential applications in lift and thrust enhancement.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Chemistry, Multidisciplinary
Yuanbo Dong, Bifeng Song, Wenqing Yang, Dong Xue
Summary: The design of flapping wings is challenging due to the complexity of tailoring the wing flexibility and selecting favorable kinematics. This study developed an optimization model to improve energy efficiency by optimizing wing geometric and kinematic parameters. Surrogate optimization was used to solve the design optimization model. The optimized flapping wing features large geometrical parameters, a moderate amplitude of the flapping angle, and low frequency, providing guidance for optimal flapping wing designs.
APPLIED SCIENCES-BASEL
(2023)
Article
Engineering, Mechanical
Longfei Cong, Bin Teng, Lifen Chen, Wei Bai, Ruijia Jin, Biaosong Chen
Summary: The excellent aerodynamic performance of birds and bats during flying and propulsion has been studied by adopting a low aspect-ratio wing flapping in uniform flow. A bio-inspired flow controlling strategy based on active wing-chord adjustment has been proposed to achieve aerodynamic enhancement. The effects of stretching pattern and aspect ratio on the aerodynamic performance of the wing have been investigated. The results show that in-phase active controlling delays Leading Edge Vortex (LEV) detachment and enhances Trailing Edge Vortex (TEV), while out-phase wing-chord adjustment leads to flow separation and performance deterioration of the wing. The study also reveals that the aerodynamic performance of the flapping wing is susceptible to the stretching phase of wing-chord.
JOURNAL OF FLUIDS AND STRUCTURES
(2023)
Article
Engineering, Aerospace
Wei Gao, Yishu Liu, Qifu Li, Bei Lu
Summary: A rapid modeling approach, based on the unsteady vortex lattice method and potential flow theory, is developed for aerodynamic computation of multi-lifting surfaces. The approach allows for quick integration and meshing of multiple lifting surfaces with different geometric parameters and grid divisions. Physical influence between lifting surfaces and wake-surface interaction are modeled, and different built-in vortex core models are used. Trajectory data is used to replace pre-calculated downwash superposition for boundary condition integration, and instantaneous boundary condition is generated directly from the kinematic states and mesh messages of the model concerned. Considering the direct coupling effect between aerodynamics and rigid body dynamics, a function for free flight is built for medium-fidelity dynamic simulations and aerodynamic data identifications. The proposed modeling and simulation process is highly efficient and can be easily applied to models with any number of lifting surfaces and arbitrary motion modes.