A new twist on gyroscopic sensing: body rotations lead to torsion in flapping, flexing insect wings

Insects perform fast rotational manoeuvres during flight. While two insect orders use flapping halteres (specialized organs evolved from wings) to detect body dynamics, it is unknown how other insects detect rotational motions. Like halteres, insect wings experience gyroscopic forces when they are flapped and rotated and recent evidence suggests that wings might indeed mediate reflexes to body rotations. But, can gyroscopic forces be detected using only changes in the structural dynamics of a flapping, flexing insect wing? We built computational and robotic models to rotate a flapping wing about an axis orthogonal to flapping. We recorded high-speed video of the model wing, which had a flexural stiffness similar to the wing of the Manduca sexta hawkmoth, while flapping it at the wingbeat frequency of Manduca (25 Hz). We compared the three-dimensional structural dynamics of the wing with and without a 3 Hz, 10° rotation about the yaw axis. Our computational model revealed that body rotation induces a new dynamic mode: torsion. We verified our result by measuring wing tip displacement, shear strain and normal strain of the robotic wing. The strains we observed could stimulate an insect's mechanoreceptors and trigger reflexive responses to body rotations.

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Wearable Vibration Sensor for Measuring the Wing Flapping of Insects

Sensors ◽

10.3390/s21020593 ◽

2021 ◽

Vol 21 (2) ◽

pp. 593

Author(s):

Ryota Yanagisawa ◽

Shunsuke Shigaki ◽

Kotaro Yasui ◽

Dai Owaki ◽

Yasuhiro Sugimoto ◽

...

Keyword(s):

High Speed ◽

Environmental Changes ◽

Underlying Mechanism ◽

Indirect Measurement ◽

Feedback Mechanism ◽

The Body ◽

Vibration Sensor ◽

Wingbeat Frequency ◽

Film Sensor ◽

Insect Wing

In this study, we fabricated a novel wearable vibration sensor for insects and measured their wing flapping. An analysis of insect wing deformation in relation to changes in the environment plays an important role in understanding the underlying mechanism enabling insects to dynamically interact with their surrounding environment. It is common to use a high-speed camera to measure the wing flapping; however, it is difficult to analyze the feedback mechanism caused by the environmental changes caused by the flapping because this method applies an indirect measurement. Therefore, we propose the fabrication of a novel film sensor that is capable of measuring the changes in the wingbeat frequency of an insect. This novel sensor is composed of flat silver particles admixed with a silicone polymer, which changes the value of the resistor when a bending deformation occurs. As a result of attaching this sensor to the wings of a moth and a dragonfly and measuring the flapping of the wings, we were able to measure the frequency of the flapping with high accuracy. In addition, as a result of simultaneously measuring the relationship between the behavior of a moth during its search for an odor source and its wing flapping, it became clear that the frequency of the flapping changed depending on the frequency of the odor reception. From this result, a wearable film sensor for an insect that can measure the displacement of the body during a particular behavior was fabricated.

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Measuring the angle of attack of beating insect wings: robust three-dimensional reconstruction from two-dimensional images

Journal of Experimental Biology ◽

10.1242/jeb.200.21.2693 ◽

1997 ◽

Vol 200 (21) ◽

pp. 2693-2704 ◽

Cited By ~ 4

Author(s):

A Willmott ◽

C Ellington

Keyword(s):

High Speed ◽

Angle Of Attack ◽

Three Dimensional ◽

Numerical Algorithms ◽

Longitudinal Axis ◽

Wing Motion ◽

Insect Wings ◽

High Speed Film ◽

Dimensional Reconstruction ◽

Left And Right

A robust technique for determining the angle of attack of insect wings from film of free flight has to date proved elusive. This report describes the development of two new methods  the Strips and Planes techniques  which were designed to overcome some of the limitations experienced in previous studies. The accuracy and robustness of these novel methods were tested extensively using simulated hawkmoth wing outlines generated for a realistic range of wing positions and torsion. The results were compared with those from two existing methods  the Symmetry and Landmarks procedures. The performance of the latter technique will be strongly species-dependent; it could not be successfully applied to hawkmoth flight because of practical difficulties in obtaining suitable landmarks. The Planes method was the least successful of the remaining techniques, especially during those phases of the wingbeat when the orientations of the two wings relative to the camera viewpoint were similar. The Symmetry and Strips methods were tested further to investigate the effects on their performance of introducing additional camber or wing motion asymmetry. The results showed clearly that the Strips method should be the technique of choice wherever the axis of wing torsion is close to the longitudinal axis of the wing. The procedure involves the experimenter matching a model wing divided into chordwise strips to the true wing outline digitized from high-speed film. The use of strips rather than the points digitized in previous studies meant that the analysis required only one wing outline to be digitized. Symmetry of motion between the left and right wings is not assumed. The implications of requiring human input to the Strips method, as opposed to the strictly numerical algorithms of the alternative techniques, are discussed. It is argued that the added flexibility that this provides in dealing with images which have typically been recorded in suboptimal conditions outweighs the introduction of an element of subjectivity. Additional observations arising from the use of the Strips analysis with high-speed video sequences of hawkmoth flight are given.

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Mechanics of Forward Flight in Bumblebees: I. Kinematics and Morphology

Journal of Experimental Biology ◽

10.1242/jeb.148.1.19 ◽

1990 ◽

Vol 148 (1) ◽

pp. 19-52 ◽

Cited By ~ 17

Author(s):

R. DUDLEY ◽

C. P. ELLINGTON

Keyword(s):

High Speed ◽

Morphological Analysis ◽

Angle Of Attack ◽

Three Dimensional ◽

Free Flight ◽

Forward Flight ◽

Body Angle ◽

Dimensional Reconstruction ◽

High Speed Cinematography ◽

Wing Tip

Using high-speed cinematography, bumblebees in free flight were filmed over a range of forward airspeeds. A detailed description of the wing tip and body kinematics was obtained from a three-dimensional reconstruction of the twodimensional film image. A technique for determining quantitatively the angle of attack of the wing was developed. Kinematic parameters found to vary consistently with airspeed were body angle, stroke plane angle, geometrical angle of attack, and rotational angles of the wings at the ends of half-strokes. Results of a morphological analysis of the wings and bodies of thoseinsects filmed in free flight are presented for use in later calculations of the lift and power requirements of forward flight.

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Computational investigation of cicada aerodynamics in forward flight

Journal of The Royal Society Interface ◽

10.1098/rsif.2014.1116 ◽

2015 ◽

Vol 12 (102) ◽

pp. 20141116 ◽

Cited By ~ 40

Author(s):

Hui Wan ◽

Haibo Dong ◽

Kuo Gai

Keyword(s):

Vortex Ring ◽

High Speed ◽

Three Dimensional ◽

Leading Edge ◽

Ring Structure ◽

Forward Flight ◽

Edge Vortex ◽

Computational Fluid Dynamics Simulations ◽

Dynamics Simulations ◽

Wing Tip

Free forward flight of cicadas is investigated through high-speed photogrammetry, three-dimensional surface reconstruction and computational fluid dynamics simulations. We report two new vortices generated by the cicada's wide body. One is the thorax-generated vortex, which helps the downwash flow, indicating a new phenomenon of lift enhancement. Another is the cicada posterior body vortex, which entangles with the vortex ring composed of wing tip, trailing edge and wing root vortices. Some other vortex features include: independently developed left- and right-hand side leading edge vortex (LEV), dual-core LEV structure at the mid-wing region and near-wake two-vortex-ring structure. In the cicada forward flight, approximately 79% of the total lift is generated during the downstroke. Cicada wings experience drag in the downstroke, and generate thrust during the upstroke. Energetics study shows that the cicada in free forward flight consumes much more power in the downstroke than in the upstroke, to provide enough lift to support the weight and to overcome drag to move forward.

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Predictive Simulation of Underwater Implosion: Coupling Multi-Material Compressible Fluids With Cracking Structures

Volume 8A: Ocean Engineering ◽

10.1115/omae2014-23341 ◽

2014 ◽

Cited By ~ 3

Author(s):

Kevin G. Wang ◽

Patrick Lea ◽

Alex Main ◽

Owen McGarity ◽

Charbel Farhat

Keyword(s):

Structural Dynamics ◽

High Speed ◽

Three Dimensional ◽

Computational Approach ◽

Quantitative Prediction ◽

Potential Threat ◽

Two Phase ◽

Riemann Solvers ◽

Adjacent Structures ◽

Highly Nonlinear

The implosive collapse of a gas-filled underwater structure can lead to strong pressure pulses and high-speed fragments that form a potential threat to adjacent structures. In this work, a high-fidelity, fluid-structure coupled computational approach is developed to simulate such an event. It allows quantitative prediction of the dynamics of acoustic and shock waves in water and the initiation and propagation of cracks in the structure. This computational approach features an extended finite element method (XFEM) for the highly-nonlinear structural dynamics characterized by large plastic deformation and fracture. It also features a finite volume method with exact two-phase Riemann solvers (FIVER) for the solution of the multi-material flow problem arising from the contact of gas and water after the structure fractures. The Eulerian computational fluid dynamics (CFD) solver and the Lagrangian computational structural dynamics (CSD) solver are coupled by means of an embedded boundary method of second-order accuracy in space. The capabilities and performance of this computational approach are explored and discussed in the full-scale simulations of a laboratory implosion experiment with hydrostatic loading and a three-dimensional manufactured implosion problem with explosion loading.

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Photogrammetric reconstruction of high-resolution surface topographies and deformable wing kinematics of tethered locusts and free-flying hoverflies

Journal of The Royal Society Interface ◽

10.1098/rsif.2008.0245 ◽

2008 ◽

Vol 6 (33) ◽

pp. 351-366 ◽

Cited By ~ 86

Author(s):

Simon M Walker ◽

Adrian L.R Thomas ◽

Graham K Taylor

Keyword(s):

High Speed ◽

Schistocerca Gregaria ◽

Insect Flight ◽

Three Dimensional ◽

Bundle Adjustment ◽

Angle Of Incidence ◽

Insect Wing ◽

Wing Kinematics ◽

Three Dimensional Measurement ◽

Spatio Temporal

Here, we present a suite of photogrammetric methods for reconstructing insect wing kinematics, to provide instantaneous topographic maps of the wing surface. We filmed tethered locusts ( Schistocerca gregaria ) and free-flying hoverflies ( Eristalis tenax ) using four high-speed digital video cameras. We digitized multiple natural features and marked points on the wings using manual and automated tracking. Epipolar geometry was used to identify additional points on the hoverfly wing outline which were anatomically indistinguishable. The cameras were calibrated using a bundle adjustment technique that provides an estimate of the error associated with each individual data point. The mean absolute three-dimensional measurement error was 0.11 mm for the locust and 0.03 mm for the hoverfly. The error in the angle of incidence was at worst 0.51° (s.d.) for the locust and 0.88° (s.d.) for the hoverfly. The results we present are of unprecedented spatio-temporal resolution, and represent the most detailed measurements of insect wing kinematics to date. Variable spanwise twist and camber are prominent in the wingbeats of both the species, and are of such complexity that they would not be adequately captured by lower resolution techniques. The role of spanwise twist and camber in insect flight has yet to be fully understood, and accurate insect wing kinematics such as we present here are required to be sure of making valid predictions about their aerodynamic effects.

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High-speed brightfield 3-D imaging and 3-D image analysis of thick and overlapped cell clusters in cytological preparations

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100168827 ◽

1994 ◽

Vol 52 ◽

pp. 218-219

Author(s):

Robert W. Mackin

Keyword(s):

Image Analysis ◽

High Speed ◽

Three Dimensional ◽

Image Data ◽

Ccd Camera ◽

Objective Lens ◽

Array Processor ◽

Vaginal Smears ◽

Low Contrast ◽

Computer Controlled

This paper presents two advances towards the automated three-dimensional (3-D) analysis of thick and heavily-overlapped regions in cytological preparations such as cervical/vaginal smears. First, a high speed 3-D brightfield microscope has been developed, allowing the acquisition of image data at speeds approaching 30 optical slices per second. Second, algorithms have been developed to detect and segment nuclei in spite of the extremely high image variability and low contrast typical of such regions. The analysis of such regions is inherently a 3-D problem that cannot be solved reliably with conventional 2-D imaging and image analysis methods.High-Speed 3-D imaging of the specimen is accomplished by moving the specimen axially relative to the objective lens of a standard microscope (Zeiss) at a speed of 30 steps per second, where the stepsize is adjustable from 0.2 - 5μm. The specimen is mounted on a computer-controlled, piezoelectric microstage (Burleigh PZS-100, 68/μm displacement). At each step, an optical slice is acquired using a CCD camera (SONY XC-11/71 IP, Dalsa CA-D1-0256, and CA-D2-0512 have been used) connected to a 4-node array processor system based on the Intel i860 chip.

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Experimental Measurement of In-Plane Rolling Nonpneumatic Tire Vibrations Using High-Speed Imaging

Tire Science and Technology ◽

10.2346/tire.18.470101 ◽

2019 ◽

Vol 47 (3) ◽

pp. 196-210

Author(s):

Meghashyam Panyam ◽

Beshah Ayalew ◽

Timothy Rhyne ◽

Steve Cron ◽

John Adcox

Keyword(s):

High Speed ◽

Image Correlation ◽

Dynamic Mode Decomposition ◽

Dynamic Mode ◽

High Speed Imaging ◽

Correlation Algorithm ◽

Mode Decomposition ◽

Series Of Experiments ◽

Plane Deformations ◽

Dominant Frequencies

ABSTRACT This article presents a novel experimental technique for measuring in-plane deformations and vibration modes of a rotating nonpneumatic tire subjected to obstacle impacts. The tire was mounted on a modified quarter-car test rig, which was built around one of the drums of a 500-horse power chassis dynamometer at Clemson University's International Center for Automotive Research. A series of experiments were conducted using a high-speed camera to capture the event of the rotating tire coming into contact with a cleat attached to the surface of the drum. The resulting video was processed using a two-dimensional digital image correlation algorithm to obtain in-plane radial and tangential deformation fields of the tire. The dynamic mode decomposition algorithm was implemented on the deformation fields to extract the dominant frequencies that were excited in the tire upon contact with the cleat. It was observed that the deformations and the modal frequencies estimated using this method were within a reasonable range of expected values. In general, the results indicate that the method used in this study can be a useful tool in measuring in-plane deformations of rolling tires without the need for additional sensors and wiring.

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