scholarly journals Dimensional analysis of spring-wing systems reveals performance metrics for resonant flapping-wing flight

2021 ◽  
Vol 18 (175) ◽  
pp. 20200888
Author(s):  
James Lynch ◽  
Jeff Gau ◽  
Simon Sponberg ◽  
Nick Gravish
Keyword(s):  
Performance Metrics ◽  
Flapping Wing ◽  
Dynamic Efficiency ◽  
Internal Damping ◽  
Power Cost ◽  
Biologically Relevant ◽  
Wing Motion ◽  
Resonance Properties ◽  
High Dynamic ◽  
Elastic Elements

Flapping-wing insects, birds and robots are thought to offset the high power cost of oscillatory wing motion by using elastic elements for energy storage and return. Insects possess highly resilient elastic regions in their flight anatomy that may enable high dynamic efficiency. However, recent experiments highlight losses due to damping in the insect thorax that could reduce the benefit of those elastic elements. We performed experiments on, and simulations of, a dynamically scaled robophysical flapping model with an elastic element and biologically relevant structural damping to elucidate the roles of body mechanics, aerodynamics and actuation in spring-wing energetics. We measured oscillatory flapping-wing dynamics and energetics subject to a range of actuation parameters, system inertia and spring elasticity. To generalize these results, we derive the non-dimensional spring-wing equation of motion and present variables that describe the resonance properties of flapping systems: N , a measure of the relative influence of inertia and aerodynamics, and K ^ , the reduced stiffness. We show that internal damping scales with N , revealing that dynamic efficiency monotonically decreases with increasing N . Based on these results, we introduce a general framework for understanding the roles of internal damping, aerodynamic and inertial forces, and elastic structures within all spring-wing systems.

scholarly journals A Viable New Strategy for the Discovery of Peptide Proteolytic Cleavage Products in Plant-Microbe Interactions

2020 ◽  
Vol 33 (10) ◽  
pp. 1177-1188
Author(s):  
Manuel I. Villalobos Solis ◽  
Suresh Poudel ◽  
Clemence Bonnot ◽  
Him K. Shrestha ◽  
Robert L. Hettich ◽  
...  
Keyword(s):  
Performance Metrics ◽  
De Novo ◽  
Hybrid Poplar ◽  
Cell Communication ◽  
Proteolytic Cleavage ◽  
Peptide Sequencing ◽  
Root Tips ◽  
Extramatrical Mycelium ◽  
Biologically Relevant ◽  
Selective Enrichment

Small peptides that are proteolytic cleavage products (PCPs) of less than 100 amino acids are emerging as key signaling molecules that mediate cell-to-cell communication and biological processes that occur between and within plants, fungi, and bacteria. Yet, the discovery and characterization of these molecules is largely overlooked. Today, selective enrichment and subsequent characterization by mass spectrometry–based sequencing offers the greatest potential for their comprehensive characterization, however qualitative and quantitative performance metrics are rarely captured. Herein, we addressed this need by benchmarking the performance of an enrichment strategy, optimized specifically for small PCPs, using state-of-the-art de novo–assisted peptide sequencing. As a case study, we implemented this approach to identify PCPs from different root and foliar tissues of the hybrid poplar Populus × canescens 717-1B4 in interaction with the ectomycorrhizal basidiomycete Laccaria bicolor. In total, we identified 1,660 and 2,870 Populus and L. bicolor unique PCPs, respectively. Qualitative results supported the identification of well-known PCPs, like the mature form of the photosystem II complex 5-kDa protein (approximately 3 kDa). A total of 157 PCPs were determined to be significantly more abundant in root tips with established ectomycorrhiza when compared with root tips without established ectomycorrhiza and extramatrical mycelium of L. bicolor. These PCPs mapped to 64 Populus proteins and 69 L. bicolor proteins in our database, with several of them previously implicated in biologically relevant associations between plant and fungus.

Simulation and Parameter Variation of Flapping-Wing Motion Based on Dragonfly Hovering

AIAA Journal ◽  
2008 ◽  
Vol 46 (4) ◽  
pp. 918-924 ◽  
Author(s):  
John Young ◽  
Joseph C. S. Lai ◽  
Charly Germain
Keyword(s):  
Parameter Variation ◽  
Flapping Wing ◽  
Wing Motion

225 On Possibility of Human-Powered Ornithopter : Study using Optimum Flapping Wing Motion Design and CFD

2005 ◽  
Vol 2005.2 (0) ◽  
pp. 135-136
Author(s):  
Keisuke OHIRA ◽  
Koji ISOGAI ◽  
Yuichi KAMISAWA ◽  
Takaaki YAMAMOTO
Keyword(s):  
Flapping Wing ◽  
Wing Motion ◽  
Human Powered ◽  
Motion Design

scholarly journals Improving Prediction of Flapping-Wing Motion By Incorporating Actuator Constraints With Models of Aerodynamic Loads Using In-Flight Data

2017 ◽  
Vol 9 (2) ◽  
Author(s):  
John W. Gerdes ◽  
Hugh A. Bruck ◽  
Satyandra K. Gupta
Keyword(s):  
Experimental Data ◽  
Design Space Exploration ◽  
Experimental Testing ◽  
Flapping Wing ◽  
Modeling Framework ◽  
Flight Data ◽  
Flexible Wing ◽  
Wing Motion ◽  
Aerodynamic Model ◽  
Strip Theory

Flapping-wing flight is a challenging system integration problem for designers due to tight coupling between propulsion and flexible wing subsystems with variable kinematics. High fidelity models that capture all the subsystem interactions are computationally expensive and too complex for design space exploration and optimization studies. A combination of simplified modeling and validation with experimental data offers a more tractable approach to system design and integration, which maintains acceptable accuracy. However, experimental data on flapping-wing aerial vehicles which are collected in a static laboratory test or a wind tunnel test are limited because of the rigid mounting of the vehicle, which alters the natural body response to flapping forces generated. In this study, a flapping-wing aerial vehicle is instrumented to provide in-flight data collection that is unhindered by rigid mounting strategies. The sensor suite includes measurements of attitude, heading, altitude, airspeed, position, wing angle, and voltage and current supplied to the drive motors. This in-flight data are used to setup a modified strip theory aerodynamic model with physically realistic flight conditions. A coupled model that predicts wing motions is then constructed by combining the aerodynamic model with a model of flexible wing twist dynamics and enforcing motor torque and speed bandwidth constraints. Finally, the results of experimental testing are compared to the coupled modeling framework to establish the effectiveness of the proposed approach for improving predictive accuracy by reducing errors in wing motion specification.

Numerical Simulation Method for 3D Low Speed Micro Flapping-Wing with Complex Kinematics

2011 ◽  
Vol 308-310 ◽  
pp. 332-335
Author(s):  
Wen Qing Yang ◽  
Bi Feng Song ◽  
Wen Ping Song ◽  
Zhan Ke Li ◽  
Ya Feng Zhang
Keyword(s):  
Numerical Simulation ◽  
Numerical Method ◽  
Stokes Equations ◽  
Simulation Method ◽  
Flapping Wing ◽  
Design Tool ◽  
Navier Stokes ◽  
Low Speed ◽  
Wing Motion ◽  
Numerical Simulation Method

A numerical simulation method is presented in this paper for 3D low speed micro flapping-wing with complex kinematics. The main characteristics for the numerical simulation of Flapping-wing Micro Air Vehicle (FMAV) include: low speed, big range of wing motion, and complex kinematics. The low speed problem is solved by preconditioning method. The big range of wing motion problem is solved by chimera grid system. The problem of complex kinematics is solved by decomposed into three main motions, i.e. plunging, pitching, and swing respectively. The numerical method is solving the Reynolds Averaged Navier-Stokes equations for the viscous flow over micro flapping-wing. The numerical method of this paper is validated by good accordance with experimental results of reference. This method can used to simulate the aerodynamic performance of micro flapping-wing with complex kinematics in low speed and is helpful to the FMAV designers as a design tool.

Design of “Figure-8” Spherical Motion Flapping Wing for Miniature UAV

2009 ◽  
Author(s):  
Zohaib Rehmat ◽  
Jesse Roll ◽  
Joon S. Lee ◽  
Woosoon Yim ◽  
Mohamed B. Trabia
Keyword(s):  
Experimental Testing ◽  
Flapping Wing ◽  
Servo Motor ◽  
Flapping Motion ◽  
Experimental Prototype ◽  
Wing Motion ◽  
Air Vehicle ◽  
Spherical Motion

Hummingbirds and some insects exhibit a “Figure-8” flapping motion, which allows them to undergo variety of maneuvers including hovering. It is therefore desirable to have miniature air vehicle (FWMAV) with this wing motion. This paper presents a design of a flapping-wing for FWMAV that can mimic “Figure-8” motion using a spherical four bar mechanism. In the proposed design, the wing is attached to a coupler point on the mechanism, which is driven by a DC servo motor. A prototype is fabricated to verify that the design objectives are met. Experimental testing was conducted to determine the validity of the design. The results indicate good correlation between model and experimental prototype.

Sunlight-Driven Continuous Flapping-Wing Motion

2020 ◽  
Vol 12 (5) ◽  
pp. 6460-6470 ◽  
Author(s):  
Xu Dong ◽  
Jiawei Xu ◽  
Xiuzhu Xu ◽  
Shengping Dai ◽  
Xiaoshuang Zhou ◽  
...  
Keyword(s):  
Flapping Wing ◽  
Wing Motion

scholarly journals Effect of Wing Corrugation on the Aerodynamic Efficiency of Two-Dimensional Flapping Wings

2020 ◽  
Vol 10 (20) ◽  
pp. 7375
Author(s):  
Thanh Tien Dao ◽  
Thi Kim Loan Au ◽  
Soo Hyung Park ◽  
Hoon Cheol Park
Keyword(s):  
Three Dimensional ◽  
Leading Edge ◽  
Aerodynamic Performance ◽  
Flapping Wing ◽  
Flapping Wings ◽  
Two Dimensional ◽  
Aerodynamic Efficiency ◽  
Insect Wing ◽  
Wing Motion ◽  
Computational Fluid Dynamics Cfd

Many previous studies have shown that wing corrugation of an insect wing is only structurally beneficial in enhancing the wing’s bending stiffness and does not much help to improve the aerodynamic performance of flapping wings. This study uses two-dimensional computational fluid dynamics (CFD) in aiming to identify a proper wing corrugation that can enhance the aerodynamic performance of the KUBeetle, an insect-like flapping-wing micro air vehicle (MAV), which operates at a Reynolds number of less than 13,000. For this purpose, various two-dimensional corrugated wings were numerically investigated. The two-dimensional flapping wing motion was extracted from the measured three-dimensional wing kinematics of the KUBeetle at spanwise locations of r = (0.375 and 0.75)R. The CFD analysis showed that at both spanwise locations, the corrugations placed over the entire wing were not beneficial for improving aerodynamic efficiency. However, for the two-dimensional flapping wing at the spanwise location of r = 0.375R, where the wing experiences relatively high angles of attack, three specially designed wings with leading-edge corrugation showed higher aerodynamic performance than that of the non-corrugated smooth wing. The improvement is closely related to the flow patterns formed around the wings. Therefore, the proposed leading-edge corrugation is suggested for the inboard wing of the KUBeetle to enhance aerodynamic performance. The corrugation in the inboard wing may also be structurally beneficial.

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