Results 31 to 40 of about 529 (162)

Research on the Flight Performance of Biomimetic Moth Based on Flapping Function Control

Applied Sciences
Flapping flight is an important mode of insect flight, and its unique flapping motion pattern enables it to fly efficiently in complex environments. This paper takes a biomimetic moth flapping-wing aircraft as the research object and proposes a periodic ...
Yaxin Liu, Wenda Wang, Ruiqing Han, Qili Sun, Ming Zhong   +4 more
doaj   +1 more source

A wind tunnel investigation of the unsteady aerodynamic characteristics of bionic flapping wings with three-dimensional complex motion

AIP Advances, 2023
The bionic flapping wing aircraft realizes flight by imitating the structure and flapping mode of birds. In this paper, a three-dimensional composite motion aerodynamic analysis model of a bionic flapping wing is established.
Lun Li, Wencheng Wang, Xiaojin Wu
doaj   +1 more source

Flight of the dragons: a global review of migration in Odonata

Biological Reviews, EarlyView.
ABSTRACT Insects are the most abundant and ecologically important animal migrants. Yet, we know relatively little about the patterns and processes underlying insect migration. Dragonflies (Anisoptera) and damselflies (Zygoptera) comprise the ancient insect order Odonata, whose ancestors were the first organisms to fly on Earth.
Johanna S.U. Hedlund, Myles Menz, Jason W. Chapman, Alexander Hayward   +3 more
wiley   +1 more source

The Effect of Torsional and Bending Stiffness on the Aerodynamic Performance of Flapping Wing

Aerospace, 2023
For large bird-like flapping wing aircraft, the fluid–structure coupling problem is very important. Through the passive torsional deformation of the wing, sufficient thrust is generated and propulsion efficiency is ensured.
Ming Qi, Wenguo Zhu, Shu Li
doaj   +1 more source

Sliding Mode Control in Aerospace Applications: A Survey

International Journal of Robust and Nonlinear Control, EarlyView.
ABSTRACT Sliding mode control (SMC) enjoys robustness to matched and unmatched (in the case of minimum phase input‐output dynamics) bounded perturbations, and finite time convergence. Second‐order and higher‐order sliding mode control systems (2‐SMC/HOSMC) retain all the advantages of sliding mode control, but in addition can be applied to systems of ...
Yuri Shtessel, Christopher Edwards
wiley   +1 more source

Design and experiment of a bionic flapping wing mechanism with flapping–twist–swing motion based on a single rotation

AIP Advances, 2020
In the present study, a bionic flapping mechanism of a spatial six-bar configuration was designed to transform a single rotation of a motor into a three degrees of freedom “flapping–twist–swing” cooperative motion of a flapping wing. The kinematics model
Bing Ji, Qiaolin Zhu, Shijun Guo, Fan Yang, Yushuai Li, Zenggang Zhu, Si Chen, Rui Song, Yibin Li   +8 more
doaj   +1 more source

Design and Testing of a Minimal Configuration Underwater Micro‐Glider: Automating Lake and Reservoir Monitoring

Journal of Field Robotics, EarlyView.
ABSTRACT Uncrewed underwater vehicles (UUVs) have transformed oceanographic research through autonomous data gathering. Similarly, lake and other aquatic research can potentially be automated and transformed. However, UUVs would need to be smaller, lighter, less complex, and cheaper than currently available to make them more practical and user‐friendly
James M Rand, Alan Hunter, Danielle Wain, Lee D Bryant   +3 more
wiley   +1 more source

Flight Performance Estimation of Bionic Flapping-Wing Micro Air Vehicle [PDF]

Xibei Gongye Daxue Xuebao, 2018
Bionic flapping-wing micro air vehicle(MAV) has received worldwide attention.The flight performance calculation is an important step in the conceptual design.The differences in performance estimation methods between the flapping-wing and conventional ...

doaj   +1 more source

A Preliminary Exploratory Measurement Model for Systems Thinking in Defence and Aerospace Engineering: A Bifurcated Framework Developed via Multiple Correspondence Analysis

Systems Research and Behavioral Science, EarlyView.
ABSTRACT Modern engineering faces a ‘complexity crisis’ characterized by interlinked, multidisciplinary ‘wicked problems’, particularly within the defence and aerospace sectors. Although systems thinking is recognized as a critical competency for navigating this environment, empirical quantitative frameworks for its measurement remain limited.
Shimon Fridkin, Sigal Kordova
wiley   +1 more source

Can you really change your stripes? Stable wing ornamentation suggests limited condition‐dependent signalling in female common eiders

Ibis, EarlyView.
Variation in the expression of white ornaments, such as flank spots or wing stripes, has previously been related to indices of individual quality in birds. We measured the white wing stripes of colour‐banded female common eiders Somateria mollissima in three islands in Iceland from 2014 to 2023, to determine whether the expression of these ornaments is
Jón Einar Jónsson, Elisabeth Knudsen, James A. Fletcher, Ellen Magnúsdóttir, Árni Ásgeirsson, Jamie N. Carroll   +5 more
wiley   +1 more source