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The purpose of this paper is to perform an indoor autonomous flight of ornithopter using a novel motion capture system.

The ornithopter platform has no on‐board sensors and processors for state estimation or feedback control. Instead, passive markers on the ornithopter body reflect IR light of the multiple strobing CCD cameras, and the position data of the markers are streamed to the ground station in almost real time. Control inputs such as wingbeat frequency and rudder angle are generated by the proportional feedback controllers which are implemented in the ground station and transmitted to the ornithopter. Due to the complexity and nonlinearity of aerodynamics and flexible multibody dynamics, the flight dynamics of ornithopter are difficult to realize in the closed form of state‐space system equations. A controller for stabilizing the flight state variables of ornithopter is not necessary to be implemented by means of flapping counter‐forces and torques which make ornithopter have inherent flight stability. The gains of controllers for following circular trajectories are obtained by a trial‐and‐error approach rather than a model‐based design.

The autonomous ornithopter successfully circulates the pre‐described radius with the constant altitude and the result shows that control strategies proposed in this study are sufficient to implement the autonomy of ornithopter flight.

The autonomous flight of ornithopter is firstly conducted in a confined indoor environment by using the motion capture system and the control performance is evaluated in terms of position errors.

This study aims to discuss the mathematical modelling of a compliance-assisted flapping mechanism and morphable structures for an UAV.

A compliance-assisted flapping wing was designed and modelled mathematically, and signals for the corresponding curves were calculated. The actual wing tip trace of a hummingbird was taken, and variables a, b, h and k were calculated from the image. This data was given to the mathematical model for plotting the graph, and the curve was compared with the input curve. The wing frame and mechanism for control surfaces using morphing is modelled along with single pivoted spine for centre of gravity augmentation and flight orientation control.

The model efficiently approximates the 2D path of the wing using line segments using the muscle and compliance mechanism.

Using a compliance-assisted flapping mechanism offers practical advantages. It allows us to synchronize the flapping frequency with the input signal frequency, ensuring efficient operation. Additionally, the authors can enhance the torque output by using multiple muscle strands, resulting in a substantial increase in the system’s torque-to-weight ratio. This approach proves to be more favourable when compared to conventional methods involving motors or servos, ultimately offering a more efficient and robust solution for practical application.

This model focuses on creating a flexible and tunable mechanism that can at least trace four types of wing traces from the same design, for shifting from one mode of flight to another.

Conventional ornithopter flapping mechanisms are gear or servo driven and cannot trace a wing tip, but some can trace complicated curves, but only one at a time. This model can trace multiple curves using the same hardware, allowing the user to program the curve based on their needs or bird. The authors may vary the shape of the wing tip trace to switch between forward flight, hovering, backward flying, etc., which is not conceivable with any traditional flapping mechanism.

The purpose of the work is to design a flapping wing that generates net positive propulsive force and vertical force over a flapping cycle operating at a given freestream velocity. In addition, an optimal wing is designed based on the comparison of the force estimated from the quasi‐steady theory, with the wind‐tunnel experiments. Based on the designed wing configuration, a flapping wing ornithopter is fabricated.

This paper presents a theoretical aerodynamic model of the design of an ornithopter with specific twist distribution that results generation of substantial net positive vertical force and thrust over a cycle at non‐zero advance ratio. The wing has a specific but different twist distribution during the downstroke and the upstroke that maintains the designed angle of attack during the strokes. The wing is divided into spanwise strips and Prandtl's lifting line theory is applied to estimate aerodynamic forces with the assumptions of quasi‐steady flow and the wings are without any dihedral or anhedral. Spanwise circulation distribution is obtained and hence lift is calculated. The lift is resolved along the freestream velocity and perpendicular to the freestream velocity to obtain vertical force and propulsive thrust force. Experiments are performed in a wind tunnel to find the forces generated in a flapping cycle which compares well with the theoretical estimation at low flying speeds.

The estimated aerodynamic force indicates whether the wing geometry and operating conditions are sufficient to carry the weight of the vehicle for a sustainable flight. The variation of the aerodynamic forces with varying flapping frequencies and freestream velocities has been illustrated and compared with experimental data that shows a reasonable match with the theoretical estimations. Based on the calculations a prototype has been fabricated and successfully flown.

The theory does not take into account the unsteady effects and estimates the aerodynamic forces at wing level condition. It doesn’t predict stall and ignores structural deformations due to aerodynamic loads. The airfoil section is only specified by the chord, zero lift angle of attack, lift slope, profile drag coefficient and angle of attack as given inputs. To fabricate a light weight wing that maintains a very accurate geometric twist and camber distribution as per the theoretical requirement is challenging.

Useful for designing ornithopter wing (preferably bigger) involving an unswept rigid spar with flapping and twisting.

The novelty of the present wing design is the appropriate spanwise geometric twisting about the leading edge spar.

THE helicopter was the first method of mechanical flight by which success was achieved—although only in model form. Centuries before a power‐driven model aeroplane flew, toy helicopters with some form of string or rubber “propulsion” were common objects of the nursery. As a scientific model, it dates back at least to the days of Leonardo da Vinci, among whose papers is a sketch of a practical design of a helicopter with which he experimented. This is not altogether surprising because, except for the ornithopter based on the close analogy of bird flight, it provides the most obvious method of getting off the ground, by rising direct from it.

The goal of this research is to demonstrate micro‐electro‐mechanical systems (MEMS)‐based transducers for aircraft maneuvering. Research in wind tunnels have shown that micro‐actuators can be used to manipulate leading edge vortices found on aerodynamic surfaces with moderate to highly swept leading edges, such as a delta wing. This has been labeled as the MEMS vortex shift control (MEMS‐VSC). The work presented in this paper seeks to detail the evolution of real‐world flight tests of this research using remotely piloted vehicles (RPVs).

Four different RPVs were constructed and used for flight tests to demonstrate the ability of using MEMS devices to provide flight control, primarily in the rolling axis.

MEMS devices for high angle‐of‐attack (AOA) turning flights have been demonstrated and the paper finds that the success of a complex project like the MEMS‐VSC requires the marriage of basic science expertise found in academia and the technical expertise found in industry.

Owing to the need to test fly the RPVs at low altitudes for video documentation while performing high AOA maneuvers, the attrition of the RPVs becomes the dominant factor to the pace of research.

MEMS sensors and actuators can be used to augment flight control at high AOA, where conventional control surfaces typically experiences reduced effectiveness. Separately, the lessons learned from the integration efforts of this research provide a potentially near parallel case study to the development of ornithopter‐based micro aerial vehicles.

This is the only research‐to‐date involving the demonstration of the MEMS‐VSC on real‐world flight vehicles.

The purpose of this paper is to create a conceptual design a bird-inspired unmanned aerial vehicle (UAV) that can stay in the air for a long time while this design influences the species near the airport with predator appearance. To achieve that goal, reverse engineering methods took into account to find out optimal parameter, and effective bird species were examined to be taken as an example.

Design parameters were determined according to the behaviour of bird species in the region and their natural enemies. Dalaman airport where is located near the fresh water supplies and sea, was chosen as the area to run. To keep such birds away from the airport and to prevent potential incidents, information from animal behaviour studies is enormously important. According to Tinbergen, chicken and gees reacted to all short-necked birds because they thought they were predators. The entire method is based on information from these data, along with reverse engineering principles.

UAV can remain in the air for more than 5 min when the engine stops at an altitude of 200 m. Also, when the UAV loses altitude of 100 m, it can cover a distance of about 2 m with the 19.8-glide ratio. Moreover, 380 KV brushless electric motor can provide 5.2 kg thrust force with 17 × 8-inch folding propeller which means 1.3 thrust to weight ratio (T/W). This engine and propeller combination work up to 12 min at maximum power with 7000 mAh lipo-battery. The UAV can climb more than 40 min at 0.2 T/W ratio.

While bird-inspired UAV trials have just begun, general ornithopter studies have taken smaller birds as their source because this is the limit of the flapping wing, one of the largest birds modelled in this study. Thus, it is inevitable the UAV influences other birds in the area. In addition, this bird’s inherent flight behaviour, such as soaring, ridge lifting and gliding, will increase its credibility. Owing to size similarity with UAV systems, reverse engineering methods worked well in the design.

Some of the specialist try to fly trained falcon in airport as an alternative method. This study focussed on the design of a bird-inspired UAV by optimizing the glide performance, both for scare the other birds around the airport and for the observation of birds in the vicinity and for the identification of bird species.

As this type of work has been proven to reduce the risk of bird strikes, the sense of flight safety on society will increase.

Researchers and companies generally work on flapping wing models for related subjects. However, these products are kind of model of the Falconiformes species which don’t have too much influence on big birds. For this reason, the authors took account of Imperial eagle’s specifications. These birds perform long soaring flights while seeking for prey like the glider design. So, the authors think it is a new approach for designing UAV for preventing bird-strike.

Biomimetic study existing natural biological elements to produce engineering products with similar performance and abilities. The purpose of this paper is to highlight biomimetic studies to produce a new type of airplanes: adding remiges, bending ability and flapping mechanisms.

The used methodology was to thoroughly investigate the literature, to define the proper endurance and fatigue parameters, to perform a series of numerical studies and report improvement percentages relevant to defined parameters.

By adding remiges and the bending mechanism, the authors managed to reach – numerically – the preset desired structure goal. Efficiency increased using remiges with less drag force. In addition, with the help of the bending wing technique, the drag force was improved. The flapping mechanism showed high vibration rates. Last but not least, applying multiple winglets gave a better optimization of the endurance parameter.

Research is conducted at a university without any research facilities. No laboratories exist, and acquiring research papers is mostly difficult and costly.

The research study is original in the sense of its numerical investigation. Proposing biomimetic was at the heart of the airplane invention and cannot be stated as an original contribution. Rather the field has been recently abandoned, and performing this major literature review can be considered as original in a sense it summarizes recent to somewhat old advancement.

The purpose of this paper is to experimentally analyze the effect of wing shape of various insects of different species in a flapping micro aerial vehicle (MAV).

Six different wings are fabricated for the MAV configuration, which is restricted to the size of 15 cm length and width; all wings have different surface area and constant span length of 6 cm. The force is being measured with the help of a force-sensing resistor (FSR), and the coefficients of lift were calculated and compared.

This study shows that the wing “Tipula sp” has better value of lift than other insect wings, except for the negative angle of attacks. The wing “Aeshna multicolor” gives the better values of lift in negative angles of attack.

This paper lays the foundation for the development of flapping MAVs with the insect wings. This type of wing can be used for spying purpose in the military zone and also can be used to survey remote and dangerous places where humans cannot enter.

This paper covers all basic insect wing configurations of different species with exact mimics of the veins. As the experimental investigation was carried for different angle of attacks, velocities and flapping frequencies, this paper can be used as reference for future flapping wing MAV developers.

Flapping-wing vehicles show various advantages as compared to fixed wing vehicles, making flapping-wing vehicles' study necessary in the current scenario. The present study aims to provide guidelines for fixing geometric parameters for an initial engineering design by a simple aerodynamic and flight dynamic parametric study.

A mathematical analysis was performed to understand the aerodynamics and flight dynamics of the micro-air vehicle (MAV). Only the forces due to the flapping wing were considered. The flapping motion was considered to be a combination of the pitching and plunging motion. The geometric parameters of the flapping wing were varied and the aerodynamic forces and power were observed. Attempts were then made to understand the flight stability envelope of the MAV in a forward horizontal motion in the vertical plane with similar parametric studies as those conducted in the case of aerodynamics.

From the aerodynamic study, insights were obtained regarding the interaction of design parameters with the aerodynamics and feasible ranges of values for the parameters were identified. The flapping wing was found to have neutral static stability. The flight dynamic analysis revealed the presence of an unstable oscillatory mode, a stable fast subsidence mode and a neutral mode, in the forward flight of the MAV. The presence of unstable modes highlighted the need for active control to restore the MAV to equilibrium from its unstable state.

The study does not take into account the effects of control surfaces and tail on the aerodynamics and flight dynamics of the MAV. There is also a need to validate the results obtained in the study through experimental means which shall be taken up in the future.

The parametric study helps us to understand the extent of the impact of the design parameters on the aerodynamics and stability of the MAV. The analysis of both aerodynamics and dynamic stability provides a holistic picture for the initial design. The study incorporates complex mathematical equations and simplifies such to understand the aerodynamics and flight stability of the MAV from an engineering perspective.

The study adds to already existing knowledge on the design procedures of a flapping wing.

This paper aims to provide an insight into recent miniaturised robot developments and applications.

Following an introduction, this article discusses the technology and applications of miniature robots and considers swarm robotics, assembly robots, flying robots and their uses in healthcare. It concludes with a brief consideration of the emerging field of nanorobotics.

This shows that all manners of miniaturised terrestrial, airborne and aquatic robots are being developed, but size and weight restraints pose considerable technological challenges, such as power sources, navigation, actuation and control. Prototypes have been developed for military, assembly, medical, environmental and other applications, as well as for furthering the understanding of swarm behaviour. In the longer term, microrobots and nanorobots offer prospects to revolutionise many aspects of healthcare, such as cancer treatment.

This study provides details of a wide-ranging selection of miniaturised robot developments.