Wing Motion Research Articles

Mechanics of the thorax in flies.

Insects represent more than 60% of all multicellular life forms, and are easily among the most diverse and abundant organisms on earth. They evolved functional wings and the ability to fly, which enabled them to occupy diverse niches. Insects of the hyper-diverse orders show extreme miniaturization of their body size. The reduced body size, however, imposes steep constraints on flight ability, as their wings must flap faster to generate sufficient forces to stay aloft. Here, we discuss the various physiological and biomechanical adaptations of the thorax in flies which enabled them to overcome the myriad constraints of small body size, while ensuring very precise control of their wing motion. One such adaptation is the evolution of specialized myogenic or asynchronous muscles that power the high-frequency wing motion, in combination with neurogenic or synchronous steering muscles that control higher-order wing kinematic patterns. Additionally, passive cuticular linkages within the thorax coordinate fast and yet precise bilateral wing movement, in combination with an actively controlled clutch and gear system that enables flexible flight patterns. Thus, the study of thoracic biomechanics, along with the underlying sensory-motor processing, is central in understanding how the insect body form is adapted for flight.

Developing a reduced order model from structural kinematic measurements of a flexible finite span wing in stall flutter

Experiments were conducted on a flexible, finite-span cyber–physical wing model in the wind tunnel to study the structural kinematics for a wing undergoing stall flutter. The wing model was designed to be weak in torsion and stiff in bending to exhibit stall flutter oscillations. The physical deformation of the wing surface was mapped at 38%, 58%, 78%, and 98% span using a stereo vision motion tracking system. From these measurements, the wing motion is decomposed and shown to consist of a principally torsional (pitching) oscillation consistent with the first mode for a cantilevered beam in free vibration. A two equation empirical model of the wing motion was then developed and compared to the measured stall flutter motion.

Water skating robots take off?

An insect-inspired microbot that uses the motion of its wings to skate across the surface of water at high speed is presented in work from China aimed at creating microbots that can also fly. The water strider-inspired microbot's hydrophobic legs allow it to stand on the surface of the water thanks to surface tension. Bioinspired engineering seeks to create technology based on ideas taken from the amazing and varied biology we see around us everyday. Insects are a rich source of that inspiration, with their wide range of specialised abilities, including the ability to walk on water using surface tension displayed by gerridae such as the water strider. A group of researchers at Shanghai Jiao Tong University have been working on robots that can copy this feat, because, as team member Prof. Weiping Zhang explained, “Water striders can support themselves stably and move rapidly on the water. We feel that this is a very low energy consumption mechanism, especially in insect-scale.” In this issue of Electronics Letters, Prof. Zhang and his colleagues present a micro-bionic robot that can move quickly on the water, using flapping-wings and skating-legs, and is, they say, the lightest and one of the fastest water skating robots ever developed. Weighing just 165mg, their robot can skate across the surface of water at 151mm/s but Prof. Zhang tells us that these achievements are only a part of the significance of this work, “First, the study develops an efficient movement for aquatic robots, which can significantly improve the robot's working duration and cruising radius. Second, this study successfully combines the large thrust generation mechanism of flapping-wings flight and the low resistance movement form of surface tension skating to lay the technical foundation for further development of flight-skating amphibious robots.” This study was also the world's first attempt to combine these two forms of motion, and achieved a certain degree of movement performance. Previous studies have focused on actively driving a robot's legs to achieve water skating. The leg-driving approach produces motion through direct interaction with the water surface, using a rowing-like motion to push the robot forward. Unfortunately, at higher driving frequencies it is easy to break the water surface with this skating method, so it is difficult to increase the skating speed. The Shanghai team have avoided this problem by decoupling the drive mechanism from their robot's legs. Instead of driving the legs directly they use the flapping mechanism of the robot's flexible wings as the drive mechanism; producing aerodynamic force to move the robot across the water's surface. This increases stability and allows a higher skating speed, it also improves manoeuvrability. All of which can be controlled by adjusting the frequency of flapping motion. The motion of the robot's wings is produced by lead zirconate titanate (PZT) piezoelectric actuators; a method already used in flying robot designs. The wings themselves are made from polyester film with carbon fibre ‘veins’. The microbot stands on the water surface thanks to titanium alloy legs with a hydrophobic coating. The flapping wing laser displacement test equipment in the lab at Shanghai Jiao Tong University. Inset: The robot's polyester film wings incorporate carbon fibre 'veins'. These wings, rather than the legs, are used to drive the robot's water skating. The exact details of these tiny components in combination are key to the success of the work. “The major challenges we faced were the design of the wings and legs,” says Zhang. “Aerodynamic elastic deformation of flexible wings occurs when they flap at a high frequency, while large deflection elastic deformation of the titanium alloy legs treated with hydrophobic coating also happens when it undertakes a load during the movement of robot. We must ensure the stability of the forces produced by these two kinds of deformation, through the bionic design of veins, symmetrical distribution and horizontal assembly of wings, symmetrical PZT bimorph actuator design, periodic alternating signal and centre of gravity design.” The Shangai team are now working to further optimise the structural design of their microbot and develop their multi-DOF control technology; with the ultimate aim of producing an amphibious robot that can fly and skate with multiple degrees of freedom. The next step in the work is to further study the aerodynamic control mechanism and attempt to change the amplitude and direction of the aerodynamic forces produced in order to achieve transition between flight and water-skating. In terms of using such robots they foresee applications in aquatic detection, signal collection, military reconnaissance, marine meteorology and water pollution monitoring. “With such low-cost, low-power, fast-moving microbots as a platform, a mobile sensor network can be built up, effective distributed operations can be achieved as well.”

Freedom of Expression: what lessons should we learn from US experience?

Abstract Freedom of Expression is becoming a theme of growing importance and visibility in Brazil. Newspapers report daily legal suits against “hate speech” concerning race and religious discrimination. Many courts are also imposing high compensation damages that are challenging the “right to ridicule” in comedy shows and newspapers cartoons. The Brazilian public opinion in general tends to be sympathetic to more restrictive rules that may threaten freedom of expression in Brazil. There is nowadays in Brazil an unexpected agreement among the right wing, religious groups, and many human rights movements that support a European model of free speech. In many ways, the “Brazilian Model” based on balancing doctrine and a vague conceptualization of Human Dignity gives a lot of discretion for courts to decide the limits of freedom of expression. Court decisions based on balancing rhetoric is becoming dominant in Brazilian Constitutional court and usually try to avoid some epistemological issues concerning objectivity and moral justification. This article advocates that Brazilian interpretation of freedom expression has a lot to learn from the US model and doctrine. The US more strict and conceptual jurisprudence on this issue offers a powerful and democratic alternative to the balancing model and represents a rich conceptual analysis still unknown by Brazilian courts.

Experimental investigation of wing flexibility on force generation of a hovering flapping wing micro air vehicle with double wing clap-and-fling effects

Experimental investigation of wing flexibility on vertical thrust generation and power consumption in hovering condition for a hovering Flapping-Wing Micro Air Vehicle, namely FlowerFly, weighing 14.5 g with a 3 g onboard battery and having four wings with double wing clap-and-fling effects, was conducted for several wing configurations with the same shape, area, and weight. A data acquisition system was set up to simultaneously record aerodynamic forces, electrical power consumption, and wing motions at various flapping frequencies. The forces and power consumption were measured with a loadcell and a custom-made shunt circuit, respectively, and the wing motion was captured by high-speed cameras. The results show a phase delay of the wing tip displacement observed for wings with high flexible leading edge at high frequency, resulting in less vertical thrust produced when compared with the wings with less leading edge flexibility at the same flapping frequency. Positive wing camber was observed during wing flapping motion by arranging the wing supporting ribs. Comparison of thrust-to-power ratios between the wing configurations was undertaken to figure out a wing configuration for high vertical thrust production but less power consumption.

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

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.

Experimental optimization of wing shape for a hummingbird-like flapping wing micro air vehicle

Flapping wing micro air vehicles (MAVs) take inspiration from natural fliers, such as insects and hummingbirds. Existing designs manage to mimic the wing motion of natural fliers to a certain extent; nevertheless, differences will always exist due to completely different building blocks of biological and man-made systems. The same holds true for the design of the wings themselves, as biological and engineering materials differ significantly. This paper presents results of experimental optimization of wing shape of a flexible wing for a hummingbird-sized flapping wing MAV. During the experiments we varied the wing ‘slackness’ (defined by a camber angle), the wing shape (determined by the aspect and taper ratios) and the surface area. Apart from the generated lift, we also evaluated the overall power efficiency of the flapping wing MAV achieved with the various wing design. The results indicate that especially the camber angle and aspect ratio have a critical impact on the force production and efficiency. The best performance was obtained with a wing of trapezoidal shape with a straight leading edge and an aspect ratio of 9.3, both parameters being very similar to a typical hummingbird wing. Finally, the wing performance was demonstrated by a lift-off of a 17.2 g flapping wing robot.

Direct Visual Observation of Wing Movements during the Honey Bee Waggle Dance

Recruitment-related behaviours such as waggle dances enable honey bee foragers to inform their nestmates about the location of important resources. However, it is still not known how the information contained in a dance performed in the darkness of the nest is transferred to followers. Although, there are findings indicating that dancing honey bees produce airborne sounds which may convey the information, there has only been indirect evidence that moving wings are the source of these airborne sounds. In this study, honey bee dances were recorded using a high-speed camera in order to directly observe and precisely measure the frequency of wing beats and abdomen wags of dancers. Dancing bees moved their wings for 40.4% of the duration of a waggle run and for only 8.1% of the duration of a circle run. The episodes of wing movements consisted of one to five wing beats and were separated by intervals of motionless wings. The mean frequency of wing beats was 167.0 Hz and significantly differed depending on the number of wing beats in one episode (p < 0.001) and the position of the wings (p = 0.007). The mean frequency of abdomen wags was 14.6 Hz. The mean number of followers was 7.9 and significantly more of them gathered around the abdomens of dancers than around their heads and thoraxes (p = 0.001). The results of this study support the assumption that moving wings are the source of airborne sounds emitted during honey bee dances.

On the fluid-structure interaction of flexible membrane wings for MAVs in and out of ground-effect

Wind tunnel experiments are conducted at a Reynolds number of Re=56,000, measuring rigid flat-plates and flexible membrane wings from free-flight into ground-effect conditions. Load cell measurements, digital image correlation and particle image velocimetry are applied in high-speed to resolve time-synchronised lift, drag and pitch oscillations simultaneously with membrane and flow dynamics. Proper orthogonal decomposition is applied on flow oscillations to determine their spatiotemporal evolution. Loads, membrane motions and flow dynamics are correlated to each other to investigate their underlying coupling physics. A membrane wing's ability of static cambering and dynamic membrane oscillations are found to be beneficial when the wing is in ground-effect, where the descent in height forces premature leading-edge vortex-shedding and drag increase. The dynamic motions of membrane wings help to exploit vortex-shedding dynamics from the leading-edge that ensures time-averaged reattached flow over the wing upper surface, resulting in further lift enhancement. Membrane wings show lag-free fluid-membrane coupling at peak-lift conditions. In post-stall conditions, the membrane is found to lag the flow dynamics, signalling the end of direct fluid-structure coupling.

An experimental study of elastic properties of dragonfly-like flapping wings for use in biomimetic micro air vehicles (BMAVs)

This article studies the elastic properties of several biomimetic micro air vehicle (BMAV) wings that are based on a dragonfly wing. BMAVs are a new class of unmanned micro-sized air vehicles that mimic the flapping wing motion of flying biological organisms (e.g., insects, birds, and bats). Three structurally identical wings were fabricated using different materials: acrylonitrile butadiene styrene (ABS), polylactic acid (PLA), and acrylic. Simplified wing frame structures were fabricated from these materials and then a nanocomposite film was adhered to them which mimics the membrane of an actual dragonfly. These wings were then attached to an electromagnetic actuator and passively flapped at frequencies of 10–250Hz. A three-dimensional high frame rate imaging system was used to capture the flapping motions of these wings at a resolution of 320 pixels×240 pixels and 35000 frames per second. The maximum bending angle, maximum wing tip deflection, maximum wing tip twist angle, and wing tip twist speed of each wing were measured and compared to each other and the actual dragonfly wing. The results show that the ABS wing has considerable flexibility in the chordwise direction, whereas the PLA and acrylic wings show better conformity to an actual dragonfly wing in the spanwise direction. Past studies have shown that the aerodynamic performance of a BMAV flapping wing is enhanced if its chordwise flexibility is increased and its spanwise flexibility is reduced. Therefore, the ABS wing (fabricated using a 3D printer) shows the most promising results for future applications.

How flies are flirting on the fly

BackgroundFlies have some of the most elaborate visual systems in the Insecta, often featuring large, sexually dimorphic eyes with specialized “bright zones” that may have a functional role during mate-seeking behavior. The fast visual system of flies is considered to be an adaptation in support of their advanced flight abilities. Here, we show that the immense processing speed of the flies’ photoreceptors plays a crucial role in mate recognition.ResultsVideo-recording wing movements of abdomen-mounted common green bottle flies, Lucilia sericata, under direct light at 15,000 frames per second revealed that wing movements produce a single, reflected light flash per wing beat. Such light flashes were not evident when we video-recorded wing movements under diffuse light. Males of L. sericata are strongly attracted to wing flash frequencies of 178 Hz, which are characteristic of free-flying young females (prospective mates), significantly more than to 212, 235, or 266 Hz, characteristic of young males, old females, and old males, respectively. In the absence of phenotypic traits of female flies, and when given a choice between light emitting diodes that emitted either constant light or light pulsed at a frequency of 110, 178, 250, or 290 Hz, males show a strong preference for the 178-Hz pulsed light, which most closely approximates the wing beat frequency of prospective mates.ConclusionsWe describe a previously unrecognized visual mate recognition system in L. sericata. The system depends upon the sex- and age-specific frequencies of light flashes reflecting off moving wings, and the ability of male flies to distinguish between the frequency of light flashes produced by rival males and prospective mates. Our findings imply that insect photoreceptors with fast processing speed may not only support agile flight with advanced maneuverability but may also play a supreme role in mate recognition. The low mating propensity of L. sericata males on cloudy days, when light flashes from the wings of flying females are absent, seems to indicate that these flies synchronize sexual communication with environmental conditions that optimize the conspicuousness of their communication signals, as predicted by sensory drive theory.

Flies compensate for unilateral wing damage through modular adjustments of wing and body kinematics.

Using high-speed videography, we investigated how fruit flies compensate for unilateral wing damage, in which loss of area on one wing compromises both weight support and roll torque equilibrium. Our results show that flies control for unilateral damage by rolling their body towards the damaged wing and by adjusting the kinematics of both the intact and damaged wings. To compensate for the reduction in vertical lift force due to damage, flies elevate wingbeat frequency. Because this rise in frequency increases the flapping velocity of both wings, it has the undesired consequence of further increasing roll torque. To compensate for this effect, flies increase the stroke amplitude and advance the timing of pronation and supination of the damaged wing, while making the opposite adjustments on the intact wing. The resulting increase in force on the damaged wing and decrease in force on the intact wing function to maintain zero net roll torque. However, the bilaterally asymmetrical pattern of wing motion generates a finite lateral force, which flies balance by maintaining a constant body roll angle. Based on these results and additional experiments using a dynamically scaled robotic fly, we propose a simple bioinspired control algorithm for asymmetric wing damage.

Comparison of the Regulation of Contraction in Insect Flight Muscle and Vertebrate Cardiac Muscle

The indirect flight muscle of insects (IFM), such as Drosophila and Lethocerus, is activated by periodic stretches at a priming concentration of calcium. The alternate activation of opposing muscles produces the rapid wing movements needed for flight. Cardiac muscle develops more force at longer sarcomere lengths (length-dependent activation), and force is enhanced by a rapid stretch at each beat. Troponin bridges between thick and thin filaments have been identified in Lethocerus IFM (Perz-Edwards et al, 2014) and these may be stretch sensors. Cardiac TnC and the TnC-F2 isoform in IFM both bind one regulatory calcium in the N-lobe. The force-pCa curve for IFM with only the TnC-F2 isoform (pCa50 5.8 and co-operativity nH 3.2) is similar to that of cardiac trabeculae, suggesting the co-operative behaviour is produced in the same way. TnC-F1, the IFM isoform needed for stretch activation, binds one calcium in the C-lobe, which is not regulatory. The force-pCa curve for IFM fibres, in which TnC-F1 is the main isoform, shows greater calcium-sensitivity and less co-operativity (pCa50 6.2, nH 1.3). The force-pCa curve of IFM fibres is similar to that of cardiac trabeculae with bound C1-C2 fragment of MyBP-C, in which calcium-sensitivity is increased and co-operativity greatly reduced. In this case, cardiac and IFM fibres achieve the same mechanical properties by different mechanisms. In order to determine if troponin forms part of a link between thick and thin filaments in IFM, we have tested binding between a tropomyosin-troponin complex and isolated thick filaments or myosin. The subunits of tropomyosin-troponin and the conditions needed for binding will be described.

The Function and Organization of the Motor System Controlling Flight Maneuvers in Flies

Animals face the daunting task of controlling their limbs using a small set of highly constrained actuators. This problem is particularly demanding for insects such as Drosophila, which must adjust wing motion for both quick voluntary maneuvers and slow compensatory reflexes using only a dozen pairsof muscles. To identify strategies by which animals execute precise actions using sparse motor networks, we imaged the activity of a complete ensemble of wing control muscles in intact, flying flies. Our experiments uncovered a remarkably efficient logic in which each of the four skeletal elements at the base of the wing are equipped with both largephasically active muscles capable of executing largechanges and smaller tonically active muscles specialized for continuous fine-scaled adjustments. Based on the responses to a broad panel of visual motion stimuli, we have developed a model by which the motor array regulates aerodynamically functional features of wing motion. VIDEO ABSTRACT.

Study on lift enhancement of a flapping rotary wing by a bore-hole design

A novel design of a micro air vehicle with flapping rotary wings was recently proposed. In this paper, the investigation is focused on aerodynamic enhancement of a bore-hole and an elastic cover added onto an intact flapping rotary wing. The aerodynamic force and the pitching motion of the perforated wing are both acquired in experiments. In comparison with an intact wing, a typical perforated wing shows a significant decrement in negative lift and thus a higher mean lift. As a supporting process, the computational fluid dynamics method is then employed to analyze the flow around the wing and the hole, and thereby make clear the underlying physical mechanism. It is found the hole opens due to the cover deflection in a passive manner and produces a secondary starting vortex on the wing lower surface of the cover during upstrokes. Together with the tip vortex around the lateral edges of the cover, the resulting vortex significantly reduces the magnitude of the negative lift, and thus explains the mean-lift enhancement in a flapping cycle. Additionally, the mean-lift enhancement correlates with the geometric parameters of the hole. An increment up to 40% in maximum mean lift is identified for a perforated wing in comparison with an intact wing. These results indicate that a bore-hole design could be a promising approach to enhance the aerodynamic lift of a flapping rotary wing.

Immersion and invariance-based adaptive wing rock control with nonlinear terminal manifold

This paper develops a new adaptive control system based on the immersion and invariance (I&I) theory for the wing rock motion control using state variable feedback. An I&I-based adaptive control system is designed for the regulation of the roll angle trajectory to a nonlinear terminal manifold. The trajectory evolving on this manifold converges to the origin in a finite time. The control system includes a control module and a parameter estimator which can be tuned independently for shaping the responses. A special feature of this adaptive law is that once the estimated parameters coincide with the actual values, then subsequently these parameter estimates remain frozen, and adaptation stops. Furthermore the trajectories of the closed-loop system eventually evolve on a manifold in an extended state space. Simulation results are presented which show that the adaptive controller suppresses the wing rock motion of delta wing at different angles of attack, despite uncertainties.

Take-off mechanisms in parasitoid wasps.

High-speed video analyses of the natural behaviour of parasitoid wasps revealed three strategies used to launch the insects into the air. Which strategy is the most energy efficient? In Pteromalus puparum, 92% of take-offs by were propelled entirely by movements of the middle and hind legs, which were depressed at their coxo-trochanteral and extended at their femoro-tibial joints. The front legs left the ground first, followed by the hind legs, so that the middle legs provided the final propulsion. Second, in other species of a similar mass, Cotesia glomerata and Leptopilina boulardi, all take-offs were propelled by a mean of 2.8 and 3.8wingbeats, respectively, with little or no contribution from the legs. The first strategy resulted in take-off times that were four times shorter (5 versus 22.8 ms) and take-off velocities that were four times faster (0.8 versus 0.2 m s-1). Calculations from the kinematics indicate that propulsion by the legs was the most energy-efficient strategy, because more energy is put into propulsion of the body, whereas in take-off propelled by repetitive wing movements energy is lost to generating these movements and moving the air. In heavier species such as Netelia testacea and Amblyteles armatorius, take-off was propelled by the combined movements of the middle and hind legs and wingbeats. In A. armatorius, this resulted in the longest mean take-off time of 33.8 ms but an intermediate take-off velocity of 0.4 m s-1 In all three strategies the performance could be explained without invoking energy storage and power amplification mechanisms.

Numerical computation of aerodynamic noise of two tandem circular cylinders and flapping wing motion based on immersed boundary method

With the continuous development of theories, numerical computations and computational conditions, computational aero-acoustics presents huge advantages when they are used to solve the aerodynamic noise. Under low Mach number, objects with complex geometric profiles were selected as the research objects to research their aerodynamic noises at stationary and motion conditions by means of hybrid flow and sound separation algorithm for aerodynamic noise based on immersed boundary method (IBM). Firstly, the incompressible flow field was solved based on immersed boundary method, in order to obtain the flow field parameters as the input values, and solve the linearized acoustic perturbation compressible equation under non-uniform Cartesian meshes. As a result, the generation and diffusion of acoustic waves can be simulated. The circumferential flow field of two tandem circular cylinders was firstly completed and compared with the published test results to verify its reliability of the method proposed in this paper. And at different observation points, the noise distribution characteristics of two tandem circular cylinders were studied, showing that the noise in the vertical plane was distributed symmetrically and its noise intensity was greater than that in the horizontal plane. Moreover, the effect of different cylindrical diameters on radiation noise distribution was also studied, showing that the larger the cylindrical diameter was, the radiation noise close to the cylinder was smaller. Sound radiation problems of flapping wing motion were further studied by IBM, and this model was featured with obvious directivity in terms of its acoustic radiation, similar to the dipole sound source, and obvious periodicity regarding its acoustic pressure distribution. With good generality and practicability, this method can be also used for solving aerodynamic noise problems of other machines.

Unsteady aerodynamic and optimal kinematic analysis of a micro flapping wing rotor

Inspired by the high performance of rotary and insect flapping wings capable of vertical take-off and landing and hovering (VTOLH), a novel flapping wing rotor (FWR) has been developed by combining the above two types of wing motions. The FWR offers an alternative configuration for micro air vehicles (MAV) of such high flight performance. Unlike the well-studied aerodynamics of rotary and insect-like flapping wing with prescribed wing motion, the aerodynamic lift and efficiency of the FWR associated with optimal kinematics of motion has not been studied in a systematic manner before. This investigation is therefore focused on the FWR optimal kinematic motion in terms of aerodynamic lift and efficiency. Aerodynamic analysis is conducted for a FWR model of aspect ratio 3.6 and wing span 200 mm in a range of kinematic parameters. The analysis is based on a quasi-steady aerodynamic model with empirical coefficients and validated by CFD results at Re∼3500. For comparison purpose, the analysis includes rotary and insect-like flapping wings in hovering status with the FWR at an equilibrium rotation speed when the thrust equals to drag. The results show that the rotary wing has the greatest power efficiency but the smallest lift coefficient. Whereas the FWR can produce the greatest aerodynamic lift with power efficiency between rotary and insect-like flapping wings. The results provide a quantified guidance for design option of the three types of high performance MAVs together with the optimal kinematics of motion according to flight performance requirement.

Observations and Measurements of Wing Parameters of the Selected Beetle Species and the Design of a Mechanism Structure Implementing a Complex Wing Movement

Beetle wings perform a flapping movement, consisting of the rotation relative to the two axes. This paper presents the results of observations and measurements of wings operating parameters in different planes of some beetle species. High speed photos and videos were used. The concept of the mechanism performing a complex wing movement was proposed and developed.