Cormorant Webbed-feet Support Water-surface Takeoff: Quantitative Analysis via CFD

Huang, Jinguo; Liang, Jianhong; Yang, Xingbang; Chen, Hongyu; Wang, Tianmiao

doi:10.1007/s42235-021-00090-z

Cited by 3 publications

(2 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Upon locating its target, the osprey promptly adjusts its posture and swoops downward [26]. As it descends towards the water surface, its wings swiftly tuck back and shorten [27]. Figure 1(a) shows the picture of osprey hunting.…”

Section: Structural Design 21 Bionic Inspirationmentioning

confidence: 99%

Design of bionic active folding flapping wing vehicle

Zhang,

Yu,

Dong

et al. 2024

Eng. Res. Express

View full text Add to dashboard Cite

Flapping wing vehicles mimic the wing flapping of flying creatures such as birds, bats and insects, and are characterized by simplicity, lightness, good concealment, high maneuverability and diversified flight attitudes. Currently, the development of wing-fluttering vehicles mainly focuses on wing-fluttering configurations, while there is little research on mimicking the large-scale active folding of wings of birds and bats. Here, we developed two types of large-scale folding wing vehicles with light mass and actively folded wings respectively, based on the property that the wings of flying organisms can be actively folded and contracted in a large scale, and tested their flight capabilities. The test results show that the latter vehicle, which combines the flapping wing mechanism and the active folding mechanism, has good flight performance and is able to accomplish the airborne folding of the wings on the basis of the flapping wing flight.

show abstract

Section: Structural Design 21 Bionic Inspirationmentioning

confidence: 99%

Design of bionic active folding flapping wing vehicle

Zhang,

Yu,

Dong

et al. 2024

Eng. Res. Express

View full text Add to dashboard Cite

show abstract

“…Conceptually, the flexibility and potency of the cormorant flippers are considered the foremost features for an optimal swimming performance. We previously studied the high-speed flapping motion of the cormorant flippers during the water surface takeoff, [15][16][17] in which the flippers are modeled as solid bodies or piece models. To handle the oscillatory motions of the biomimetic flippers with a strong resemblance, we need to investigate the dynamic musculoskeletal architecture modeling with compliant mechanics.…”

Section: Introductionmentioning

confidence: 99%

Biorobotic Waterfowl Flipper with Skeletal Skins in a Computational Framework: Kinematic Conformation and Hydrodynamic Analysis

Huang

Wang

Liang

et al. 2023

Advanced Intelligent Systems

Self Cite

View full text Add to dashboard Cite

Cormorants (Phalacrocoraxe), types of aquatic birds, utilize the compliance/flexibility of the flippers and exploit hydrodynamic/biomechanic processes to accomplish diverse operations. Particularly, the flipper‐propelled locomotion exhibits traits such as super‐redundancy and large deformations, necessitating depiction of both movements of the rigid skeletons as well as local deformations of the soft tissues. However, there are few well‐established kinematic/hydrodynamic framework models and constitutive equations for such rigid–flexible intrinsically coupled biosystems. Herein, combined with a skeletal skinning algorithm to handle the deformation of a flexible body attached to a rigid body, a numerical computation framework for an in‐depth fluid–structure interaction is presented, which enables the capture of viscoelastic and anisotropic characteristics of a highly compliant 3D rigid–flexible coupled model in a low‐Reynolds‐number flow. Considering the biorobotic cormorant flipper with a nonuniformly distributed stiffness as a representative, the challenging issue of controlling a biomechanically compliant flipper to synthesize realistic locomotion sequences, including rigid skeleton movements and soft tissue deformations, is addressed. Furthermore, a numerical computational hydrodynamic analysis is performed to demonstrate that the cormorant flipper can generate 5 N fluid force and 0.45 N m fluid moment during the turning operation in 0.8 s, which is consistent with the former experimental results.

show abstract

The hydrodynamic performance of duck feet for submerged swimming resembles oars rather than delta-wings

Ribak,

Gurka

2023

Sci Rep

View full text Add to dashboard Cite

Waterfowl use webbed feet to swim underwater. It has been suggested that the triangular shape of the webbed foot functions as a lift-generating delta wing rather than a drag-generating oar. To test this idea, we studied the hydrodynamic characteristics of a diving duck’s (Aythya nyroca) foot. The foot’s time varying angles-of-attack (AoAs) during paddling were extracted from movies of ducks diving vertically in a water tank. Lift and drag coefficients of 3D-printed duck-foot models were measured as a function of AoA in a wind-tunnel; and the near-wake flow dynamics behind the foot model was characterized using particle image velocimetry (PIV) in a flume. Drag provided forward thrust during the first 80% of the power phase, whereas lift dominated thrust production at the end of the power stroke. In steady flow, the transfer of momentum from foot to water peaked at 45° < AoA < 60°, due to an organized wake flow pattern (vortex street), whereas at AoAs > 60° the flow behind the foot was fully separated, generating high drag levels. The flow characteristics do not constitute the vortex lift typical of delta wings. Rather, duck feet seem to be an adaptation for propulsion at a wide range of AoAs, on and below the water surface.

show abstract

Cormorant Webbed-feet Support Water-surface Takeoff: Quantitative Analysis via CFD

Abstract: z. The Version of Record is the version of the article after copy-editing and typesetting, and connected to open research data, open protocols, and open code where available. Any supplementary information can be found on the journal website, connected to the Version of Record.

Cited by 3 publications

References 42 publications

Design of bionic active folding flapping wing vehicle

Design of bionic active folding flapping wing vehicle

Biorobotic Waterfowl Flipper with Skeletal Skins in a Computational Framework: Kinematic Conformation and Hydrodynamic Analysis

The hydrodynamic performance of duck feet for submerged swimming resembles oars rather than delta-wings

Contact Info

Product

Resources

About